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ARCHIVE: TCP-IP Distribution List - Archives (1986)
DOCUMENT: TCP-IP Distribution List for September 1986 (154 messages, 75675 bytes)
SOURCE: http://securitydigest.org/exec/display?f=tcp-ip/archive/1986/09.txt&t=text/plain
NOTICE: securitydigest.org recognises the rights of all third-party works.

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-----------[000000][next][prev][last][first]----------------------------------------------------
Date:      Tue, 2-Sep-86 03:18:43 EDT
From:      JNC@XX.LCS.MIT.EDU ("J. Noel Chiappa")
To:        mod.protocols.tcp-ip
Subject:   Re: Possible DDN to Ethernet or 802.3 Gateway Vendors


	Let me correct some slight errors in that posting about the
Proteon entry: a) Proteon does not yet have a DDN X.25 interface, but
hope to have one soon; b) for details please *do not* contact me, but
call Proteon at 617-655-3340.

	Noel
-------

-----------[000001][next][prev][last][first]----------------------------------------------------
Date:      Tue, 2-Sep-86 09:45:00 EDT
From:      DCP@QUABBIN.SCRC.Symbolics.COM (David C. Plummer)
To:        mod.protocols.tcp-ip
Subject:   How to IP & ARP on 802 Nets


    Date: 29 Aug 1986 19:27:12 PDT
    From: POSTEL@B.ISI.EDU

    Hello. 
Hi.

    At an ad hoc special session on "IEEE 802 Networks and ARP" held
    during the recent TCP Vendors Workshop, an approach to a consistent
    way to sent DOD-IP datagrams and other IP related protocols on 802
    networks was developed.

    [...]

A very quick reading of this and a small amount of knowledge about 802.x
leads me to believe this looks reasonable.  The problem I see is "What
happens if ISO blesses DoD IP and then there are two different ways to
talk it?"

    The total length of the SAP Header and the SNAP header is 8-octets,
    making the 802.2 protocol overhead come out on a nice octet boundary.

Good.

    If we can not quickly resolve the issue of the values for K1 and K2,
    we will push for the assignment of a sap value (a K1 value) to
    indicate "IP related protocols" and do our own multiplexing (much like
    that proposed above).

Please don't say "IP related protocols."  Only one protocol is IP
related and that is IP.  Instead say "Ethernet'1980 related protocols"
which includes Chaos, PUP, XNS, DECnet, etc.

-----------[000002][next][prev][last][first]----------------------------------------------------
Date:      Wed,  3-SEP-1986 17:20 EDT
From:      Ronald A. Jarrell  <JARRELLRA%VTVAX3.BITNET@WISCVM.WISC.EDU>
To:        <tcp-ip@sri-nic.arpa>
Subject:   nsfnet


We plan on hooking to nsfnet in the near future, probably through a sattelite
link and an imp.  We were going to be running Wollongong's WIN on the Vaxes,
but I've been told we are going to have a horrible time with it, that it
wouldn't work with out a lot of kluding.. Anyone have suggestions as to a
good, full-function, tcpip package to use in this situation?  It would
need ddn protocol support, and be able to talk to unix flavor systems.

Please also mention whether or not it would require new hardware, or if
we could share the deuna we currently have for decnet and lat.


Also, while I'm thinking of it, anyone have PD or non-PD code for domain
support for a VMS system?

-Ron
-----------[000003][next][prev][last][first]----------------------------------------------------
Date:      Tue, 2-Sep-86 14:20:46 EDT
From:      jas@BRUBECK.PROTEON.COM
To:        mod.protocols.tcp-ip
Subject:   Re: How to IP & ARP on 802 Nets

Your K1 (the SNAP SAP) is '01010101' when presented least signifigant
bit first. (First bit to the MAC layer first.) For those of us who think
in a forward direction, this is '10101010', or 'AA'hex.

While SNAP is only a proposal, I beleive it is de-facto real. I understand
that certain proprietary network vendors already plan to use it.

By the way, "ethernet types" were handed over by Xerox to the IEEE along
with the 24-bit address blocks. There is no list available from IEEE of
the allocation of either type of block, they consider that proprietary.

I have heard rumors that K2 is '0', and that this 24-bit block belongs to Xerox.
Are the Xerox people out there who can confirm this?

					john shriver
					proteon
-------

-----------[000004][next][prev][last][first]----------------------------------------------------
Date:      Tue, 2-Sep-86 14:27:27 EDT
From:      jas@BRUBECK.PROTEON.COM
To:        mod.protocols.tcp-ip
Subject:   Re: How to IP & ARP on 802 Nets

There already was a blessed way to send IP packets over 802.2. The problem
was that the powers that be were NEVER going to provide a SAP for ARP,
so the IP SAP was useless. Once we had this scheme for ARP, we decided
to do IP that way to provide an even-length data-link header, and one the
same size as ARP. (DoD Internet is SAP '06'hex.)
-------

-----------[000005][next][prev][last][first]----------------------------------------------------
Date:      Wed, 3 Sep 86 23:45 PDT
From:      Provan@LLL-MFE.ARPA
To:        tcp-ip@sri-nic.arpa
Subject:   re: How to IP & ARP on 802 nets

I have two problems with this scheme.  Unfortunately, both are caused by
the SNAP, which seems to be the part closest to being fully blessed.

The first problem is the 24 bit "organization" code.  A 24 bit field
seems excessively clumsy.  (In the immortal words of 1822, it's "not
particularly convenient for anyone.")  Not too serious, but it fits well
with my solution.

The second problem is that this plan works great with 802.2 type 1
headers, but 802.2 type 2 messages add an additional byte to the normal
802.2 header.  If the SNAP scheme is unchanged in this situation, we
find ourselves with the new ethernet type field shifted back to an odd
byte and our IP packet gets out of alignment.  Does anyone know what
happens to the SNAP in type 2?  I don't know if it's feasible to send IP
packets over type 2 802.2, but if it is we need to worry about this.

I have a solution that solves both of these problems.  Instead of a 24
bit organization code, break it into an eight bit unused pad field
followed by a 16 bit organization code.  (Happily, this field is then
aligned to an even byte.)  In type 2 802.2 packets, this unused eight
bits becomes the second byte of the 802.2 control field, but the other
four bytes of the SNAP (two for the organization code and two for the
new ethernet type field) remain the same.  So the 802.2 header would be
the same size (eight bytes) for both type 1 and type 2 packets, rather
than have the three byte header for type 1 and the four byte header for
type 2 in the currently published protocol.

Of course, this assumes we have anything to say about this.  Since this
doesn't appear to be the case, i guess it's too late to avoid these
problems.

Looking back on this note, i realize that someone without familiarity
with 802.2 might be confused.  I think i can lessen the confusion by
explaining that 802.2 packets, including these three or four (or eight)
byte headers, ride inside 802.3 packets, which have the familiar 14
byte ethernet header, with the ethernet type field replaced by the
famous 802.3 length field.

While i have the floor, at the TCP workshop, i think i heard twice that
802.3 lengths less than 60 are illegal, and, therefore, fall under the
famous ethernet footnote, which says that any illegal lengths can be
interpreted however the implementation wants (thus allowing previous
ethernet implementations to continue to operate on the same network as
802.3 impelmentations).  If i heard correctly, i'd like to point out
that this is not correct.  Lengths less than 60 are legal in 802.3.  In
fact, it's the need to express a packet smaller than 60 bytes in a
hardware environment which doesn't allow transmission of packets less
60 bytes in length that is the justification for the length field in
the first place.  (A packet can be padded out to 60 bytes while the
true length of the packet is preserved via the length field.)

						don provan
						provan@lll-mfe.arpa
-----------[000006][next][prev][last][first]----------------------------------------------------
Date:      Thu, 4-Sep-86 02:01:55 EDT
From:      JARRELLRA@VTVAX3.BITNET (Ronald A. Jarrell)
To:        mod.protocols.tcp-ip
Subject:   nsfnet



We plan on hooking to nsfnet in the near future, probably through a sattelite
link and an imp.  We were going to be running Wollongong's WIN on the Vaxes,
but I've been told we are going to have a horrible time with it, that it
wouldn't work with out a lot of kluding.. Anyone have suggestions as to a
good, full-function, tcpip package to use in this situation?  It would
need ddn protocol support, and be able to talk to unix flavor systems.

Please also mention whether or not it would require new hardware, or if
we could share the deuna we currently have for decnet and lat.


Also, while I'm thinking of it, anyone have PD or non-PD code for domain
support for a VMS system?

-Ron

-----------[000007][next][prev][last][first]----------------------------------------------------
Date:      Thu, 4-Sep-86 02:14:56 EDT
From:      mrose@NRTC-GREMLIN.ARPA (Marshall Rose)
To:        mod.protocols.tcp-ip
Subject:   The ISO Development Environment at NRTC

[ multiple appologies for posting this to multiple lists... ]

/mtr
-----
			 A N N O U N C E M E N T


    The first release of the ISO Development Environment at NRTC is
    available for distribution.  This release is called

				ISODE 1.0

    This software supports the development of certain kinds of
    ISO/CCITT/ECMA protocols and applications.  

    Here are the details:

	 - ISODE is not proprietary, but it is not in the public domain.
	   This was necessary to include a "hold harmless" clause in the
	   release.  The upshot of all this is that anyone can get a
	   copy of the release and do anything they want with it, but
	   no one takes any responsibility whatsoever for any (mis)use.

	 - ISODE runs on native 4.2BSD and SVR2 with an Excelan card
	   (Future releases will support VAX/VMS and a variant of PC/IP.)

	 - Current modules include:
		TSAP	- makes TCP look like TP4
		SSAP	- ISO BCS session
		PSAP	- ASN.1 encoding
		PEPY	- ASN.1 yacc-like facility
		RoSAP	- ECMA Remote Operations Services

	 - Although the ISODE is not "supported" per se, it does have a
	   problem-reporting address, ISO-People@NRTC.NORTHROP.COM.  Bug
	   reports (and fixes) are welcome by the way.  


    The primary documentation for this release consists of a User's
    Manual (approx 150 pages) and a set of UNIX manual pages.  The
    sources to the User's Manual are in LaTeX format.  In addition,
    there are a number of notes, papers, and presentations included in
    the documentation set, again in either LaTeX or SLiTeX format.  


    There are two ways to get a distribution:

    1.  If you can FTP to the ARPA Internet, use anonymous FTP to
    louie.udel.edu [10.0.0.96] and retrieve the file portal/isode-1.tar.
    This is a tar image (approx 2.0MB).  The file portal/isode-1.tar.Z is
    the tar image after being run through the compress program (approx 0.8MB).

    2. Send a magtape and a self-addressed mailing label to:

	Northrop Research and Technology Center
	Attn: Automation Sciences Laboratory (0330/T30)
	One Research Park
	Palos Verdes Peninsula, CA  90274
	USA

	+1-213/544-5393

    We will write the tape in tar format at 1600bpi, and return it with
    a copy of the User's manual.  

-----------[000008][next][prev][last][first]----------------------------------------------------
Date:      Thu, 4-Sep-86 02:45:00 EDT
From:      Provan@LLL-MFE.ARPA
To:        mod.protocols.tcp-ip
Subject:   re: How to IP & ARP on 802 nets


I have two problems with this scheme.  Unfortunately, both are caused by
the SNAP, which seems to be the part closest to being fully blessed.

The first problem is the 24 bit "organization" code.  A 24 bit field
seems excessively clumsy.  (In the immortal words of 1822, it's "not
particularly convenient for anyone.")  Not too serious, but it fits well
with my solution.

The second problem is that this plan works great with 802.2 type 1
headers, but 802.2 type 2 messages add an additional byte to the normal
802.2 header.  If the SNAP scheme is unchanged in this situation, we
find ourselves with the new ethernet type field shifted back to an odd
byte and our IP packet gets out of alignment.  Does anyone know what
happens to the SNAP in type 2?  I don't know if it's feasible to send IP
packets over type 2 802.2, but if it is we need to worry about this.

I have a solution that solves both of these problems.  Instead of a 24
bit organization code, break it into an eight bit unused pad field
followed by a 16 bit organization code.  (Happily, this field is then
aligned to an even byte.)  In type 2 802.2 packets, this unused eight
bits becomes the second byte of the 802.2 control field, but the other
four bytes of the SNAP (two for the organization code and two for the
new ethernet type field) remain the same.  So the 802.2 header would be
the same size (eight bytes) for both type 1 and type 2 packets, rather
than have the three byte header for type 1 and the four byte header for
type 2 in the currently published protocol.

Of course, this assumes we have anything to say about this.  Since this
doesn't appear to be the case, i guess it's too late to avoid these
problems.

Looking back on this note, i realize that someone without familiarity
with 802.2 might be confused.  I think i can lessen the confusion by
explaining that 802.2 packets, including these three or four (or eight)
byte headers, ride inside 802.3 packets, which have the familiar 14
byte ethernet header, with the ethernet type field replaced by the
famous 802.3 length field.

While i have the floor, at the TCP workshop, i think i heard twice that
802.3 lengths less than 60 are illegal, and, therefore, fall under the
famous ethernet footnote, which says that any illegal lengths can be
interpreted however the implementation wants (thus allowing previous
ethernet implementations to continue to operate on the same network as
802.3 impelmentations).  If i heard correctly, i'd like to point out
that this is not correct.  Lengths less than 60 are legal in 802.3.  In
fact, it's the need to express a packet smaller than 60 bytes in a
hardware environment which doesn't allow transmission of packets less
60 bytes in length that is the justification for the length field in
the first place.  (A packet can be padded out to 60 bytes while the
true length of the packet is preserved via the length field.)

						don provan
						provan@lll-mfe.arpa

-----------[000009][next][prev][last][first]----------------------------------------------------
Date:      Thu, 4-Sep-86 05:07:22 EDT
From:      steve@BRL.ARPA (Stephen Wolff)
To:        mod.protocols.tcp-ip
Subject:   Re:  nsfnet

I've been told SRI  markets a competitive package, but I've lost the
reference.  Help, someone?		-s

-----------[000010][next][prev][last][first]----------------------------------------------------
Date:      Thu, 4 Sep 86 5:07:22 EDT
From:      Stephen Wolff <steve@BRL.ARPA>
To:        "Ronald A. Jarrell" <JARRELLRA%VTVAX3.BITNET@wiscvm.wisc.edu>
Cc:        tcp-ip@sri-nic.arpa
Subject:   Re:  nsfnet
I've been told SRI  markets a competitive package, but I've lost the
reference.  Help, someone?		-s

-----------[000011][next][prev][last][first]----------------------------------------------------
Date:      4 Sep 1986 06:24-EDT
From:      CERF@A.ISI.EDU
To:        JARRELLRA%VTVAX3.BITNET@WISCVM.WISC.EDU
Cc:        tcp-ip@SRI-NIC.ARPA
Subject:   Re:  nsfnet
Ron,

without commenting on the Wollongong software, which I am not qualified to
express an opinion about since I have not used it nor reviewed its operation
in detail, there is a lengthy publication available from the SRI NIC, and
also available on line, I believe, listing quite a number of commercial
TCP/IP related products. I don't have the book here with me but urge you
to investigate via the NIC.

Of course, you should get some interesting replies from the TCP-IP 
distribution list, too. There is only modest support for VMS, as I
recall, as the bulk of the implementations stem from the Berkeley
UNIX effort (perhaps 50% are derived in that fashion).

Vint
-----------[000012][next][prev][last][first]----------------------------------------------------
Date:      5 Sep 1986 11:03-PDT
From:      Mike StJohns <StJohns@SRI-NIC.ARPA>
To:        tcp-ip@SRI-NIC.ARPA
Subject:   1822 vs 1822L Survey
I  need to know what implementations use what version of the 1822
protocol to talk to their IMPs.  If you are an implementer,  tell
me  whether  your implementation talks 1822 or 1822L or both.  If
you have an X25 implementation, I would appreciate knowing  about
that  also.   Reply  directly  to me and I will summarize for the
network.  Implementers only please....  can you imagine how large
my  mailbox  will  be if everyone replied.  Thanks, Mike StJohns,
DCA B612
-----------[000013][next][prev][last][first]----------------------------------------------------
Date:      Fri, 5-Sep-86 16:03:59 EDT
From:      klem@BRL.ARPA
To:        mod.protocols.tcp-ip
Subject:   (none)

Subject: imprecise DDN X.25 specification?
Newsgroups: mod.protocols.tcp-ip
Distribution: usa
To: tcp-ip@sri-nic.arpa
Keywords: DDN X.25 CDC



We have a contract with CDC to build and install an interface from a CDC
Cyber 750 running NOS to a MILNET IMP.  The contractors attended a 3-day
TCP/IP Vendor Workshop in Monterey last month.  They came away from the
meeting with lots of questions.  Can anyone answer the concerns that were
surfaced at the meeting (see below for the contractor's questions)?

-------------------------------------------------------------------------

It was stated that the contractor can be implementing X.25 in agreement with
the contract specification, pass the DCA Qualification Test and not be able
to communicate with the IMP.  This is a result of the imprecise DDN X.25
specification and the incompleteness of the X.25 Qualification Testing.  

One X.25 issue that was discussed was the X.25/1822 incompatibility on the
network. It is our understanding that the government has developed hardware
and software solutions and has the situation under control.

Other issues that could affect the CDC interface to the IMP include:

1) CDC X.25 does not establish a virtual circuit for each and every local
network destination host and corresponding precedence.

2) CDC will provide the destination address to the IMP through the IP
header, as opposed to the X.25 header.

3) CDC will not map an IP address into X.25 and vice-versa.

Is it true that any or all of the above issues will create problems in the
CDC interface with the DDN?

---------------------------------------------------------------------------

Thanks,
George Klem <klem@brl.arpa>

-----------[000014][next][prev][last][first]----------------------------------------------------
Date:      Fri, 5 Sep 86 16:03:59 EDT
From:      klem@BRL.ARPA
To:        tcp-ip@sri-nic.arpa
Subject: imprecise DDN X.25 specification?
Newsgroups: mod.protocols.tcp-ip
Distribution: usa
To: tcp-ip@sri-nic.arpa
Keywords: DDN X.25 CDC



We have a contract with CDC to build and install an interface from a CDC
Cyber 750 running NOS to a MILNET IMP.  The contractors attended a 3-day
TCP/IP Vendor Workshop in Monterey last month.  They came away from the
meeting with lots of questions.  Can anyone answer the concerns that were
surfaced at the meeting (see below for the contractor's questions)?

-------------------------------------------------------------------------

It was stated that the contractor can be implementing X.25 in agreement with
the contract specification, pass the DCA Qualification Test and not be able
to communicate with the IMP.  This is a result of the imprecise DDN X.25
specification and the incompleteness of the X.25 Qualification Testing.  

One X.25 issue that was discussed was the X.25/1822 incompatibility on the
network. It is our understanding that the government has developed hardware
and software solutions and has the situation under control.

Other issues that could affect the CDC interface to the IMP include:

1) CDC X.25 does not establish a virtual circuit for each and every local
network destination host and corresponding precedence.

2) CDC will provide the destination address to the IMP through the IP
header, as opposed to the X.25 header.

3) CDC will not map an IP address into X.25 and vice-versa.

Is it true that any or all of the above issues will create problems in the
CDC interface with the DDN?

---------------------------------------------------------------------------

Thanks,
George Klem <klem@brl.arpa>

-----------[000015][next][prev][last][first]----------------------------------------------------
Date:      Fri, 5-Sep-86 18:25:31 EDT
From:      cetron@UTAH-CS.ARPA (Edward J Cetron)
To:        mod.protocols.tcp-ip
Subject:   Re: nsfnet

-------------------------- the standard sacrificial line

	We have been using the Tektronix tcp/ip package for quite a
few months and have found it extremely useful... A quick summary:

	Advantages (especially vs. WIN/VX)

	1. you are given ALL of the source code (albeit in bliss)
	2. the code is NATIVE-style NOT a unix port
	3. it has proved to be very reliable, easy to modify for local
		hacks/improvements
	4. with very few exceptions, it is very clean, readable code which
		tends to follow the tcp mil-std very well....
	5. with the software tools message system (public domain from lbl)
		it also will support smtp as per rfc 822, 821....
	6. it is virtually free for an educational institutional site license.

	Disadvantages:

	1. It is available currently only to educational institutions (but
		some commercial sites HAVE gotten access to it).
	2. it currently only supports telnet, ftp, 3com ftp, and smtp
	3. there is no support (but then i understand the Wollongong doesn't
		support there product either in reality)
	4. it does not yet support nameservers, >255 hosts, and anything other
		than in its fixed host table (however; we are currently fixing
		these problems and hope to have them resolved within 2 months)


	All in all, compared to WIN/VX (which i HAVE used) i feel that it is
infinitely superior (and much cheaper).  While it isn't perfect (yet) you have
the code to fix whatever ails it.  One of our sites has been using it for 3
months with NO MAJOR COMPLAINTS  except when the WIN/VX site that they talk
to screws up.

	I would be happy to answer any further questions or supply details
if people would like...

-ed cetron
center for engineering design
Univ. of Utah

cetron%utah-cbd@utah-cs.arpa


	

-----------[000016][next][prev][last][first]----------------------------------------------------
Date:      Sat, 6-Sep-86 05:02:54 EDT
From:      mckee@MITRE.ARPA
To:        mod.protocols.tcp-ip
Subject:   Gateway Selection Procedure


Gentlemen:

I solicit advice and document references on how IP should select a
particular Gateway when more than one is available.

Background

My responsibilities include writing communications and network
performance requirements for a large military system called the WWMCCS
Information System (WIS).  The WIS will (initially) consist of about 40
sites.  Each site will have:
  
    - a 10 Mbps Applitek LAN

    - 2 or 3 large host processors

    - 50 to 150 workstations

The workstations and hosts are connected to the LAN through Interface
Units (IUs).  TCP and IP are performed in the IUs.

Each LAN has at least one Gateway IU that connects the LAN to the
DDN-RVN (DDN-Red Virtual Network, Class A Net 21).  All inter-site
communications use net 21.  For increased throughput and availability,
some sites will have 2 or 3 Gateway IUs.  Some Gateways will connect to
the DDN-RVN at 56 Kbps, others at 9.6 Kbps.

Each LAN has a LAN Control Center/Security Monitor (CC/SM).  For
security and access control, procedures have been established such that
the CC/SM is aware of the status of every connection; every TCP active
or passive open/close/abort request is routed through the CC/SM.
Further, by means of periodic interrogation, the CC/SM knows the health
and traffic load of every local IU, including the local Gateways.

Questions

When IP in a host or workstation IU receives a datagram destined for a
remote site, what procedure should be used to select one of the local 
Gateways?

When IP in a Gateway receives a datagram from the LAN, what procedure
should be used to select one of the Gateways at the remote site?

Any advice or references would be appreciated.

H. Craig McKee
'mckee at mitre'
(703)883-5505

-----------[000017][next][prev][last][first]----------------------------------------------------
Date:      Sun, 7-Sep-86 02:12:37 EDT
From:      Murray.pa@XEROX.COM
To:        mod.protocols.tcp-ip
Subject:   Re: Ethernet between buildings

If you can possibly find the $ for the fibers, that's the way to go. If
you talk to anybody in the fiber business, this is probably the first
application they will mention. 

I suggest a very cautious, respectful approach when dealing with things
as potent as lightning. You may think your buildings are both grounded
but at the currents developed near lightning strikes, all sorts of
unobvious things will happen.

Consider what will happen when your whole net goes down. You may only
have a few machines today, but you know that more be running tomorrow.
People will be using them for term projects and writing their thesis.
Networks are addicting. Remember that it will happen durning the end of
term rush.

We have one (coax) ethernet under the street to another building. 6 or 7
years ago, a lightning bolt hit the hill a bit beyond that building. It
fried the front end transistor in dozen or so transcievers. Each fried
transistor was a short accross the coax. That whole net was down until
they found the last dead transciever. There were lots of people milling
around the halls and grumbling... (At least we could scrounge enough
transcievers on short notice to get everybody back on the air.)

(That was a long time ago. A simple resistor in the right place will
probably provide enough protection. Most transcievers probably include
one now.)

-----------[000018][next][prev][last][first]----------------------------------------------------
Date:      7 Sep 1986 05:24-EDT
From:      CERF@A.ISI.EDU
To:        mckee@MITRE.ARPA
Cc:        tcp-ip@SRI-NIC.ARPA
Subject:   Re: Gateway Selection Procedure

Mr. McKee -

you should be able to "pick any" of the known available gateways - if you
picked the wrong one, relative to minimum delay routing, that one will
"redirect" you to the right one. However, it is possible the one you picked
is dead. If the subnet you use to reach that gateway tells you about dead
hosts, as the ARPANET does, then you will be able to detect this mistake
and change your tables to select another gateway. 

There is no existing algorithm for selectively routing traffic across
multiple gateways. Dave Mills tried one that resulted in every other
packet landing in the Atlantic Ocean (The "Atlantic Two-Step"). It is
not even clear that such bifurcation oftraffic across a single TCP
logical connection would be a good idea - especially if the two routes
have widely differing delay/loss characteristics - the TCP level
performance monitoring and feedback control might have a lot of trouble
trying to adapt if every other packet, for instance, went a different
way with very different parametric profile.

Vint
-----------[000019][next][prev][last][first]----------------------------------------------------
Date:      7 Sep 1986 05:40-EDT
From:      CERF@A.ISI.EDU
To:        klem@BRL.ARPA
Cc:        tcp-ip@SRI-NIC.ARPA

Wow!

A fast reading of your message, especially the last part characterizing the DCD
X.25, suggest you are in trouble.

The IMP does NOT, so far as I know, examine the IP for an address. The host
or front end doing the IP has to map the internet address into an appropriate
X.25 address (to the destination or to the gateway on the X.25 network).

It is not necessarily a requirement that each TCP connection be mapped into
a distinct X.25 virtual circuit. Some implementations map all TCP connections
into a single X.25 virtual circuit between source and destination or source
and gateway. This could result in poorer throughput as the number of TCP
connections increases and also result in some interference between the varius
communicating processes sharing the common virtual circuit. Since there is
no easy way to tell IP that it is handling a new TCP connection, this is an 
area of performance concern which may have implementation and/or application
specific consequences and require specific remedies.

BBN has developed software which permits 1822 and X.25 interoperability;
however, there are two modes of X.25 interface on the network: standard
and basic. The basic mode is incapable of dealing with the X.25/1822
mapping since it is really just an end/end X.25 pipe - the commercial
interface to X.25 that BBN sells. The Standard mode (DoD standard) will
support 1822/X.25 interfacing. ALL of X.25 is terminated in the IMP
at the interface. At the destination, if the interface is also Standard
X.25 (not BASIC X.25), the full X.25 is RECREATED. If the destination
is 1822, it will see a fabricated 1822 exchange.  In the STANDARD case,
X.25 and 1822 addresses are mapped back and forth.

There was indication at the Monterey meeting that the STANDARD X.25 mode
had not necessarily been installed on both the ARPANET and MILNET -
the DDN NIC would be a good place to query in this regard.

The principle issue is whether the typical commercial implementations
of X.25 are compatible with (interoperate with) the DoD Standard X.25.
They certainly SHOULD interoperate with BASIC X.25. 

The reason there are two X.25 style interfaces is that the BASIC mode was
readily available and permitted hosts with vendor-specific protocols to
use the MILNET for communications, independent of interoperability with
other hosts on the system.

If all hosts used X.25 interfaces, I believe there would be no need for
the Standard X.25 interface with its conversion facility - but this is
not the case.

I'm sure you'll get other comments on the TCP-IP distribution.

Maybe we need an RFC laying all this out...

Vint
-----------[000020][next][prev][last][first]----------------------------------------------------
Date:      Sun, 7-Sep-86 17:32:27 EDT
From:      haverty@CCV.BBN.COM
To:        mod.protocols.tcp-ip
Subject:   Re: Gateway Selection Procedure


Vint et al,

A minor clarification.  There is no general algorithm in use
which spreads traffic across multiple gateways.  There is however
a special-purpose table-driven algorithm in the Arpanet/Milnet
mailbridges, which attempts to spread traffic amongst the seven
parallel mailbridges.  It is effective only for hosts which are
physically connected to the Arpanet or Milnet, but not gateways,
because hosts listen (should at least) to redirects but gateways
do not.  Fortunately this covers a lot of the traffic; without
this mechanism, the mailbridge would be a highly reliable
bottleneck (more so than it is now), since only one path would be
"best", with six !! idle backup gateways at any time.
Unfortunately, with more LANs all the time, this interim approach
is clearly limited. 

There is a feature in design stages now for the C/30 family,
which will permit multipath routing to occur -- i.e., between
points A and B several parallel paths might exist, and all might
be in use to carry traffic.  With such a mechanism, for example,
a network with only 9.6 kilobit/sec trunks could achieve a
host-host throughput greater than 9.6 by using the multiple
paths.  This is a very hard problem, to achieve stability and
efficiency and avoid behavior like the Atlantic two-step.

Jack Haverty

-----------[000021][next][prev][last][first]----------------------------------------------------
Date:      Sun, 7-Sep-86 18:12:56 EDT
From:      jas@BRUBECK.PROTEON.COM.UUCP
To:        mod.protocols.tcp-ip
Subject:   Re: re: How to IP & ARP on 802 nets

SNAP is not 'our' protocol, any more than 802.2 is ours. We don't
have any contorl over it. If we had wanted to avoid this mess, we (sigh)
should have been on 802.2. AS I noted, vendors are already using
SNAP.

The reason that the code is 3 bytes of owner, and two of protocol
number, is that they can then use the already-allocated 24-bit
prefixes that define 48-bit address blocks. Hey, 48-bits is absurdly
long, also.

I think that running a datagram network protocol like IP over class 2 802.2
is a non-sequitor, so we don't need to worry about it. I will admit that
I can't see how SNAP would work with class 2 at all. In the ISO world,
class 1 is used with connectionless internet at the network level, and
class 2 with a null network layer.

					john shriver
					proteon
-------

-----------[000022][next][prev][last][first]----------------------------------------------------
Date:      Sun,  7 Sep 86 18:12:56 EDT
From:      jas@brubeck.proteon.com
To:        Provan@LLL-MFE.ARPA
Cc:        tcp-ip@sri-nic.arpa
Subject:   Re: re: How to IP & ARP on 802 nets
SNAP is not 'our' protocol, any more than 802.2 is ours. We don't
have any contorl over it. If we had wanted to avoid this mess, we (sigh)
should have been on 802.2. AS I noted, vendors are already using
SNAP.

The reason that the code is 3 bytes of owner, and two of protocol
number, is that they can then use the already-allocated 24-bit
prefixes that define 48-bit address blocks. Hey, 48-bits is absurdly
long, also.

I think that running a datagram network protocol like IP over class 2 802.2
is a non-sequitor, so we don't need to worry about it. I will admit that
I can't see how SNAP would work with class 2 at all. In the ISO world,
class 1 is used with connectionless internet at the network level, and
class 2 with a null network layer.

					john shriver
					proteon
-------

-----------[000023][next][prev][last][first]----------------------------------------------------
Date:      Mon, 8-Sep-86 11:30:43 EDT
From:      JNC@XX.LCS.MIT.EDU.UUCP
To:        mod.protocols.tcp-ip
Subject:   Re: Gateway Selection Procedure


	The answer to the first question you ask is contained in two RFC's
in the TCP/IP guide; I don't remember which volume they are in in the
white books, but they are RFC's 814 and 816, "Names, Addresses, Ports and
Routes", and "Fault Isolation and Recovery". I don't want to sound like a
broken record, but I wish people would read the documentation provided
before asking questions. I am aware that those books contain a lot of
material: perhaps the NIC could include a 'Suggested Readings' list in
the next printing which would list RFC's 813-817 as 'Required'?
	The second question is sort of covered by RFC's 904 and 888, which
describe the current Internet model for routing packets among gateways.

	Noel
-------

-----------[000024][next][prev][last][first]----------------------------------------------------
Date:      Mon, 8-Sep-86 16:48:00 EDT
From:      MAB@CORNELLC.BITNET.UUCP
To:        mod.protocols.tcp-ip
Subject:   Anybody Have Code for an Echo Host?

At the TCP/IP Vendor's Workshop in Monterey, mention was made of a beast
called an "Echo Host".  As I understand it, this is a tool for shaking out
a host implementation of TCP/IP.  It simply echoes IP datagrams, with
controls for delay, bandwidth, and error rate.

Does anyone have code for an Echo Host?  In particular for an IBM PC?
Also, mention was made at the workshop of the existence of a How-To-
Build-An-Echo-Host RFC.  I can't find it - can someone tell me the number?

My Internet address is:
     mab%cornellc.bitnet@wiscvm.wisc.edu

-----------[000025][next][prev][last][first]----------------------------------------------------
Date:      Mon, 8 Sep 1986 16:48 EDT
From:      Mark Bodenstein  <MAB%CORNELLC.BITNET@WISCVM.WISC.EDU>
To:        <tcp-ip@sri-nic.arpa>
Subject:   Anybody Have Code for an Echo Host?
At the TCP/IP Vendor's Workshop in Monterey, mention was made of a beast
called an "Echo Host".  As I understand it, this is a tool for shaking out
a host implementation of TCP/IP.  It simply echoes IP datagrams, with
controls for delay, bandwidth, and error rate.

Does anyone have code for an Echo Host?  In particular for an IBM PC?
Also, mention was made at the workshop of the existence of a How-To-
Build-An-Echo-Host RFC.  I can't find it - can someone tell me the number?

My Internet address is:
     mab%cornellc.bitnet@wiscvm.wisc.edu
-----------[000026][next][prev][last][first]----------------------------------------------------
Date:      Mon, 8-Sep-86 20:17:38 EDT
From:      MDCG.HRD%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU ("Hank R. "Jim" Dixon")
To:        mod.protocols.tcp-ip
Subject:   X25 implementations

Hello, does anybody happen to know about any exsisting implkementations
for X25 on the VAX under either VMS (preferably) or UNIX?? Thank you.
                   JIM

-------

-----------[000027][next][prev][last][first]----------------------------------------------------
Date:      Mon, 8-Sep-86 20:44:04 EDT
From:      lekash@AMES-NASB.ARPA (John Lekashman)
To:        mod.protocols.tcp-ip
Subject:   hyperchannel and IP

Hi there.

two things:
1. I've been doing some work on an NSC hyperchannel device driver.
I started with what was working on 4.2, and with help from Mike
Karels at Berkeley, have got it working on 4.3 unix. Its available
on ames-nasb in /usr/ftp, including 4.3 kernel changes, (to support
raw access) cray research's cxint (yuk!) and hyroute (also yuk!)

2. While getting this working, I found many things about how
it functions in need of repair or improvement.  I am interested
in starting a mailing list of people who use hyperchannels on
IP nets.  I want to see some sort of standard about encapsulation,
routing, and raw access.  We spent a great deal of time wretching
about all sorts of things here, and finally everyone just copied
what cray research had given us, since getting them to change
was the hardest.

If no one else is currently running such a list, I will.  I
have created hy-people, and hy-people-request at ames-nasb.arpa
(orville).
					thank you,

					john

-----------[000028][next][prev][last][first]----------------------------------------------------
Date:      Tue, 9-Sep-86 06:55:22 EDT
From:      cel@MITRE-BEDFORD.ARPA
To:        mod.protocols.tcp-ip
Subject:   NETBIOS ISSUE---TCP Handoffs


	At the NETBIOS-TCP/IP Interface Specification Forum held Aug 28 in
Monterey, CA two proposals were discussed.  A major issue revolved around the
capability of some operating systems to support handoff of TCP connections
from one process to another.

	Are there problems in handing a TCP connection from one process to
another for some operating systems?  Which operating systems have difficulty?

	Please mail comments to netbios@mitre-bedford.arpa.


	The problem in the context of the NETBIOS issue is described below.

	Assume two hosts, one contains a client application program and the
other contains a server application program.  the problem is to establish a
session between the programs (message oriented, no loss or duplication).  The
hosts contain NETBIOS agents for their respective application programs to
interpret the various NETBIOS commands.    Also assume that the
server host contains a NETBIOS validation program that verifies if two NETBIOS
named application programs may communicate.  Exchanges may occur between the
client and validation programs via UDP messages as in proposal one or over a
TCP connection as another proposal.  Data passed over a session between
application programs occurs over a TCP connection.

	One proposal (figure A below) calls for passing all session control
information via UDP messages between the NETBIOS client program located in the
source host and the NETBIOS validation program in the destination host.
The NETBIOS Name service has provided the IP address of the server host.
The validation pgm is accessed through a TCP well known port (wkp). If the
session is valid (a server application has posted a NETBIOS listen for c-name)
then the server program does a fully specified TCP passive open using s-port,
c-port and the IP addresses.  The client program then establishes a TCP
connection to the server program using s-port, c-port, and the IP addresses.
No handoff of a TCP connection between the validation program and the server
program is required.

		Figure A: NETBIOS Names Passed via UDP

     CLIENT                                                     SERVER

							Validation pgm does
		UDP(c-name, s-name, c-port)------->     UDP wkp listen to any
	(timeout)
							agent pgm does TCP
		<--------------UDP(s-port)---------     fully spec passive
							open on s-port,c-port
						   (timeout)
		TCP(s-port) SYN ------------------>     TCP conn established
							to NETBIOS agent
		<---------------------SYN---------
		<-------------data---------------->

			     etc.

	Another proposal (figure B below) calls for the client to determine
the server's TCP port (s-port) via the NETBIOS Name service.  Meanwhile the
NETBIOS validation program posted a TCP partially specified passive open (ppo)
open on s-port due to a NETBIOS LISTEN issued by an application program.  The
client program then establishes a TCP connection to the client validation
program and passes session control information (c-name,s-name) over the
connection. If the session is valid between the two NETBIOS named
applications, then the TCP connection is handed off to the  server agent
program.  If the session is rejected then the TCP connection is broken.


		Figure B: NETBIOS Names Passed via TCP Connection

	CLIENT                                          SERVER

							Validation pgm does
							TCP ppo on s-port
		TCP(s-port) SYN----------------->
		<---------------------------SYN--
		------data(c-name, s-name)------>       Validate and handoff
							TCP conn to server
							agent pgm
	    (timeout)
		<----------data(ack, nack)-------
		<----------data----------------->

			    etc.


 Thanks,  ---- Lee LaBarre

-----------[000029][next][prev][last][first]----------------------------------------------------
Date:      9 Sep 1986 08:23-EDT
From:      CERF@A.ISI.EDU
To:        MDCG.HRD%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU
Cc:        tcp-ip@SRI-NIC.ARPA, jsol%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU
Subject:   Re: X25 implementations
Digital has a package called PSI (Version 4.0) which allows VMS to make
use of X.25 networks.

Vint Cerf
-----------[000030][next][prev][last][first]----------------------------------------------------
Date:      9 Sep 1986 08:37-EDT
From:      CERF@A.ISI.EDU
To:        tcp-ip@SRI-NIC.ARPA
Subject:   Formatting Query

I apologize for the broadcast, but I wonder if I am the only recipient of
TCP-IP distribution list messages troubled by receipt of messages containing
naked horizontal tabs (control-I characters)?

It is generally difficult to properly reconstruct the tab settings for
presentation.  If this is not just a local problem, perhaps we could
agree to expand tabs before submitting messages to TCP-IP distribution
to improve matters until someday we have a common document representation
format which can include adivce about tab settings automatically.

I recognize that such a proposal runs the risk of increasing the total
length of messages but perhaps this is a small price to pay for improved
communication.

Is anyone else out there having similar difficulties?

Vint Cerf
-----------[000031][next][prev][last][first]----------------------------------------------------
Date:      Tue, 9-Sep-86 14:40:29 EDT
From:      ahill@CC7.BBN.COM ("Alan R. Hill")
To:        mod.protocols.tcp-ip
Subject:   re: imprecise DDN X.25 specification?

George,
	As Dr. Cerf already pointed out, the concerns you have are valid
and will definitely affect the ability of the CDC interface to communicate
with the DDN Standard Service.  I cannot comment on the relationship 
between DCA Qualification and an ability to communicate effectively using
the DDN but I can offer some information on what the BBN packet switch
does during use of Standard Service.

	Standard Service will process an X.25 call by removing its
X.25 transport envelope and using the contents to generate an 1822L
envelope.  Standard  Service allows only one VC per triplet of
<source address>, <destination address>, and <precedence>.

	Unfortunately, I believe each of your issues will prevent 
communication with the DDN.  I would like to hear suggestions about
areas for improvements in the specification or the DCA Qualification.


Alan

-----------[000032][next][prev][last][first]----------------------------------------------------
Date:      Tue, 9 Sep 86 14:40:29 EDT
From:      "Alan R. Hill" <ahill@cc7.bbn.com>
To:        klem@brl.arpa
Cc:        tcp-ip@sri-nic.arpa
Subject:   re: imprecise DDN X.25 specification?
George,
	As Dr. Cerf already pointed out, the concerns you have are valid
and will definitely affect the ability of the CDC interface to communicate
with the DDN Standard Service.  I cannot comment on the relationship 
between DCA Qualification and an ability to communicate effectively using
the DDN but I can offer some information on what the BBN packet switch
does during use of Standard Service.

	Standard Service will process an X.25 call by removing its
X.25 transport envelope and using the contents to generate an 1822L
envelope.  Standard  Service allows only one VC per triplet of
<source address>, <destination address>, and <precedence>.

	Unfortunately, I believe each of your issues will prevent 
communication with the DDN.  I would like to hear suggestions about
areas for improvements in the specification or the DCA Qualification.


Alan

-----------[000033][next][prev][last][first]----------------------------------------------------
Date:      Tue, 9-Sep-86 20:22:26 EDT
From:      mike@BRL.ARPA (Mike Muuss)
To:        mod.protocols.tcp-ip
Subject:   Re:  Formatting Query

I though there was general agreement that tab stops were every 8 characters?

I don't know if this is official NETASCII, but since TOPS-20, UNIX, and VMS
all do it this way, most systems go along.
	-Mike

-----------[000034][next][prev][last][first]----------------------------------------------------
Date:      Tue, 9-Sep-86 21:03:57 EDT
From:      jcp@BRL.ARPA (Joe Pistritto, JHU|mike)
To:        mod.protocols.tcp-ip
Subject:   VMS TCP/IP over Ethernet?


	I'm working on upgrading a site that currently runs VMS on
its Vaxen to running 4.3 (at least most of the time), and the issue of
communications has come up.  Presently, there is nothing, so the slate
is clean.  I'm thinking of getting some of the Interlan (MICOM) smart
ethernet controllers, and running their VMS TCP/IP package on one machine,
with 4.3 on the others.  Has anyone else come up against the problem of
needing hardware that is both VMS and UNIX compatable, (so that either
machine can be used for either system), and found a better (more cost
effective) solution?

	The Interlan folks claim to have FTP and TELNET implemented under
VMS, I have also checked out Wollongong, any others out there I've 
missed?  Were not Government or educational, so I don't think the 
Tektronix code is available.

						-JCP-

-----------[000035][next][prev][last][first]----------------------------------------------------
Date:      Wed, 10-Sep-86 08:34:24 EDT
From:      MRC@SIMTEL20.ARPA (Mark Crispin)
To:        mod.protocols.tcp-ip
Subject:   Re: Formatting Query

Vint -

     So far as I know Multics is the only operating system in common use
on the Internet which does not use tab stops at every 8th character.  My
experience suggests that it is basically hopeless in a true heterogenous
environment to use tab stops at any other position due to the large number
of terminals which do not offer settable tab stops.

     I admit that "8 tabs" are hopelessly hacker oriented and probably
aren't santioned by any standard, but c'est la vie.  Many of the Internet
protocols are hopelessly hacker oriented.  I'm sure ISO will "improve"
this situation; I have no way of telling if ISO will do anything to improve
it though.

     If you read your mail at A.ISI.EDU (as opposed to having some agent
pick it up and pass it on to your real mailbox), you should know that
A.ISI.EDU is a TOPS-20 system and TOPS-20 uses 8 tabs exclusively.  Tenex
had programmable tabs, but this functionality was deleted in TOPS-20.
Therefore, it is correct that any terminal connected to a TOPS-20 system
should use 8 tabs.  I think the same is true for Unix and VAX/VMS.  If
not I'm sure I'll receive 1000 messages telling me what an idiot I am...

-- Mark --
-------

-----------[000036][next][prev][last][first]----------------------------------------------------
Date:      Wed, 10-Sep-86 15:51:05 EDT
From:      AI.CLIVE@MCC.COM (Clive Dawson)
To:        mod.protocols.tcp-ip
Subject:   DELNI Strangeness

Here's a bit of info to add to the general folklore:

We moved to a new building last week, and after putting everything back
together, we found that TELNET connections from our Sun workstations
to our DEC-20 (they're on separate Ethernets, gateway is a Sun) were
suffering from horribly poor throughput.  Echo delays ranged from 1 to 10
seconds, with no load to speak of on any of the systems or the nets.

After being stumped for a couple of days, we finally realized that the only
thing that had changed was that the Sun gateway and the DEC-20 were now
sharing the same DELNI, whereas before they had been on two different
DELNIs.  We made a quick switch and put the Sun onto its own transceiver
two meters away from the DELNI's transceiver.  The results were immediate
and dramatic.  Echoing delays disappeared completely and users were once
again happy.

Now the obvious question:

Does anybody have an explanation?  Is there something fundamentally 
different about intra-DELNI communication that could cause such
enormous performance problems?

Thanks,

Clive
-------

-----------[000037][next][prev][last][first]----------------------------------------------------
Date:      Wed, 10-Sep-86 16:38:21 EDT
From:      cel@MITRE-BEDFORD.ARPA
To:        mod.protocols.tcp-ip
Subject:   Postponement of NETBIOS Meeting


	The NETBIOS meeting scheduled for Sept 29 at Stanford has been
postponed.  A new meeting date has yet to be selected.

	The package containing the proposals, slide copies and issue
discussions is still being prepared.  It will be sent to the participants of
the Aug 28 meeting in Monterey, CA.

				Lee LaBarre

-----------[000038][next][prev][last][first]----------------------------------------------------
Date:      Wed, 10-Sep-86 20:19:17 EDT
From:      mike@BRL.ARPA (Mike Muuss)
To:        mod.protocols.tcp-ip
Subject:   Re:  VMS TCP/IP over Ethernet?

For VMS, also consider the Excelan board in smart mode, and maybe the
CMC people have a VMS offering too?
	-M

-----------[000039][next][prev][last][first]----------------------------------------------------
Date:      Thu, 11-Sep-86 06:57:00 EDT
From:      Walker@RADC-MULTICS.ARPA ("Robert K. Walker 'Bob'")
To:        mod.protocols.tcp-ip
Subject:   Re: Formatting Query


    Date:  9 September 1986 20:22 edt
    From:  Mike Muuss <mike at BRL>
    Subject:  Re: Formatting Query

    I though there was general agreement that tab stops were every 8 characters?

    I don't know if this is official NETASCII, but since TOPS-20, UNIX, and VMS
    all do it this way, most systems go along.
              -Mike

Tab stops every 8 characters may be the convention for DEC equipment,
which was what was mentioned.  However, the Multics convention is every
10 characters.  I have FTP'ed files from DEC machines with the tab codes
present, only to get a very ragged looking format when it is
interpretted by Multics.  This is a nuisance.

-Bob Walker-

-----------[000040][next][prev][last][first]----------------------------------------------------
Date:      Thu, 11-Sep-86 11:20:14 EDT
From:      cel@MITRE-BEDFORD.ARPA
To:        mod.protocols.tcp-ip
Subject:   NETBIOS ISSUES -- Datagram service


	At the Aug 28 NETBIOS meeting in Monterey, CA two proposals for
implementing NETBIOS on TCP/IP were discussed.  One of the areas in which
these proposals differ pertained to the NETBIOS datagram service.  The essence
of the differences relative to this area is outlined below.  We would
appreciate your comments about the relative merits and implementation
feasibility/difficulty of the alternative proposals to accomplish datagram
service.  Please send your comments to:

		netbios@mitre-bedford.arpa


      (NOTE: In both proposals IP datagrams are not broadcast out on the
	     internet, i.e. WAN.)

	First Proposal

	a) Use NETBIOS Name service to discover target UDP port and IP address
	   Since a name cache is assumed to be at each node, only infrequently
	   would name queries result in traffic on the channel.

	b) Datagrams sent to a unique name are sent as directed UDP datagrams
	   with control info and data contained within.

	c) Datagrams sent to a group name or broadcast use IP subnet broadcast


	Second Proposal

	a) All NETBIOS datagrams would be IP subnet broadcast UDP datagrams.
	   No name lookup is required.

	b) UDP datagrams would contain control info and data


	ISSUES

	1. Is the first proposal's assumption of a name cache good? (note:
	   IBM's PC Network uses a cache at each node)

	   NOTE: If a name cache is not used then each NETBIOS datagram would
		 result in a broadcast name query, one or more responses and
		 the directed UDP containing the NETBIOS datagram.  All hosts
		 would have to process the name query.

	2. Proposal two would require all hosts on the subnet to process the
	   IP datagrams - even those not using NETBIOS.  The assumption here
	   is that the NETBIOS datagram service is infrequently used and thus
	   hosts that are not the intended recipient would not be overly
	   burdened.

	   Is infrequent use of directed NETBIOS datagrams a good assumption?

	   Are slow listeners going to miss datagrams?


		       Thanks ---  Lee LaBarre

-----------[000041][next][prev][last][first]----------------------------------------------------
Date:      Thu, 11-Sep-86 12:09:00 EDT
From:      Ata@RADC-MULTICS.ARPA ("John G. Ata")
To:        mod.protocols.tcp-ip
Subject:   Re: Formatting Query


          I think the point is being missed here with regard to tab
stops.  If everyone on the network interpreted tabs the same way, this
transaction would never have been started.  Since there is variation on
tab interpretation, it would seem that if the SMTP mailers expanded the
tabs to the appropiate number of spaces, then compatability would be
assured.  The only negative effect of this might be to people who FTP
files via mail, and who might not get exactly the same file on the other
side.  However, they might wish to to use FTP instead...

                    John G. Ata

-----------[000042][next][prev][last][first]----------------------------------------------------
Date:      Thu, 11-Sep-86 14:37:16 EDT
From:      jordan@UCBARPA.BERKELEY.EDU (Jordan Hayes)
To:        mod.protocols.tcp-ip
Subject:   Re: Formatting Query


        From: "John G. Ata" <Ata@RADC-MULTICS.ARPA>

        Since there is variation on tab interpretation, it would seem
        that if the SMTP mailers expanded the tabs to the appropiate
        number of spaces, then compatability would be assured.

Wow, did this come out of left field or am I really missing
something? I don't really think you want to do this ...

/jordan

ps: maybe a better way of looking at tabs is like those stupid vt100
    escape sequences that lock up my terminal, but give an vt100'er
    double width characters ...

pss: all you UNIX'ers out there using Mail can do a ~|expand just before
     hitting ^D to end your message ... I did this for this message --
     how does it look to you Multics'ers?

-----------[000043][next][prev][last][first]----------------------------------------------------
Date:      Thu, 11-Sep-86 15:20:00 EDT
From:      JSLove@MIT-MULTICS.ARPA ("J. Spencer Love")
To:        mod.protocols.tcp-ip
Subject:   Multics TABs

Are, as several have noted, every 10 columns.

It is the position of the Multics mailer developers that TAB characters
should never be sent over the network, since there is no "standard"
width.  Thus, all outgoing mail is detabbified, at some slight cost in
network throughput.

Mail coming in is also detabbified, which affects only non-Multics mail,
since there are no tabs in mail leaving Multics.  This detabbification
*ought* to assume tabs every 8 columns, since this is the de-facto
standard.  That it doesn't is a bug (to be fair, if the mailer developer
had agreed with me, this problem would never have arisen).

None of this helps FTP users, since FTP does no TAB transformations.
There is, however, a Multics command, "canonicalize", which can insert
and remove TAB characters assuming any TAB width, which helps out in
some situations.

There are other TAB widths in use.  I think that Magic 6 uses (used?)  a
width of 5.  The width of 8 is pretty consistent across DEC equipment,
but there are other manufacturers out there.  There didn't seem to be
any consistent use of TABs at all in IBM program products, last I
checked.

Anyone out there using non-DEC and non-Honeywell gear?

-----------[000044][next][prev][last][first]----------------------------------------------------
Date:      Thu, 11-Sep-86 15:35:08 EDT
From:      ROODE%BIONET@SUMEX-AIM.STANFORD.EDU (David Roode)
To:        mod.protocols.tcp-ip
Subject:   DELNI characteristics

We have noticed that DELNI's have some non-intuitive limitations
on cable length.  Could this perhaps have some bearing on your
problem?  Unlike other multiport transceivers, the rule
for DELNI's is that the transceiver cable length limitation
of 40m (vs. 50m for other devices) applies to the sum of
lengths of the drop to the DELNI and the drop from the DELNI
to the host system.

It is also against the rules to plug one DELNI into another one
unless that DELNI is NOT connected to an Ether.
-------

-----------[000045][next][prev][last][first]----------------------------------------------------
Date:      Thu, 11-Sep-86 19:58:36 EDT
From:      leong@andrew.cmu.edu (John Leong)
To:        mod.protocols.tcp-ip
Subject:   Re: DELNI Strangeness


Clive,

I don't really know what specifically is your problem with the DELNI.
However, one thing you may care to check is this :

The DELNI (and for that matter, almost all multiport tranceiver in the
market) does not handle "heart beat" correctly. For all practical purposes,
heart beat is a kind of acknowledgment from the tranceiver to the station.
Within a very short period of time after the tranceiver finished sending the
packet into the coax cable, it issue a heart beat signal on the collision
pairs of the tranceiver cable - essentially saying "all's well". In the case
of the DELNI, this signal is (mistakenly) fanned out to ALL attached
stations. The station doing the transmit will know it is a heart beat.
However, the other attached stations will treat it as an asynchonous
collision notification. Most station will ignore it but I don't know about
the DEC-20.

However, definitely, do not attached a repeater to a DELNI. Repeater will not
toss away heart beat. It will act on it and generate collision reinforcement
(jam) on the other side!!! The result is excessive collisions. Very bad news
to the overall band width availability.

John Leong

.

-----------[000046][next][prev][last][first]----------------------------------------------------
Date:      Fri, 12 Sep 86 11:19:57 CDT
From:      Phil Howard  <PHIL%UIUCVMD.BITNET@WISCVM.WISC.EDU>
To:        TCP/IP List <TCP-IP@SRI-NIC.ARPA>
Subject:   Tabs every 8 positions
Gee, even IBM has acknowledged that tabs belong on every 8 positions.
In VM/SP/CMS's XEDIT is the EXPAND subcommand that expands out the tabs
to proper positions.  There is also COMPRESS with puts tabs in, and in
the proper place.  I use these commands to handle files received from
non-IBM systems with tabs.  Everything has worked out fine.  Now I just
need a way to get square brackets on my IBM 3178 keyboard.
-----------[000047][next][prev][last][first]----------------------------------------------------
Date:      Fri, 12-Sep-86 11:32:05 EDT
From:      jtw@mitre-bedford.ARPA (Welch)
To:        mod.protocols.tcp-ip
Subject:   RFC 912, Auth Service


I am interested in finding out whether anyone has either implemented or has
comments on the authentication protocol outlined in RFC 912, "Authentication
Service".

Any pointers or info would be appreciated.

	      Jim Welch
	      jtw@mitre-bedford

-----------[000048][next][prev][last][first]----------------------------------------------------
Date:      Fri, 12 Sep 86 11:48:14 EDT
From:      hurf@tcgould.tn.cornell.edu (Hurf Sheldon)
To:        mod.protocols.tcp-ip,,arpa.protocols.tcp-ip
Subject:   Ultrix1.2 to HPUX problem
	We recently connected a VaxstationII & an HP9000/300 via a delni
 & after getting the uvax setup correctly we then used the network setup
 program on the HP to set it up. What we get now is complete access from the
 HP to the uvax but from the uvax to the HP we get "connection refused"
 under telnet & just "time outs" on ftp & rlogin. We have set up the host tables
 on the uvax for some more HP's not yet connected & when we try to go to them
 we get a "host unreachable" so we believe the HP is recognizing it's address
 correctly but won't answer. 
	
 	We have Ultrix1.2 on the uvax & HPUX on the HP. The uvax is set
 "broadcast -trailers netmask 0xffffff00" - must be set this way to conform
 to local cornell net standards.

 Any & all suggestions appreciated.


     Hurf Sheldon			Arpa.css: Hurf@ionvax.tn.cornell.edu

     Lab of Plasma Studies	
     369 Upson Hall			phone: 607 255 7267
     Cornell University
     Ithaca, N.Y. 14853

-----------[000049][next][prev][last][first]----------------------------------------------------
Date:      Fri, 12 Sep 86 11:54:36 EDT
From:      hurf@tcgould.tn.cornell.edu (Hurf Sheldon)
To:        arpa.tcp-ip
Subject:   Ultrix to HPUX problems
	We recently connected a VaxstationII & an HP9000/300 via a delni
 & after getting the uvax setup correctly we then used the network setup
 program on the HP to set it up. What we get now is complete access from the
 HP to the uvax but from the uvax to the HP we get "connection refused"
 under telnet & just "time outs" on ftp & rlogin. We have set up the host 
 tables on the uvax for some more HP's not yet connected & when we try to
 go to them we get a "host unreachable" so we believe the HP is recognizing 
it's address correctly but won't answer. 
	
 	We have Ultrix1.2 on the uvax & HPUX on the HP. The uvax is set
 "broadcast -trailers netmask 0xffffff00" - must be set this way to conform
 to local cornell net standards.

 Any & all suggestions appreciated.


     Hurf Sheldon			Arpa.css: Hurf@ionvax.tn.cornell.edu

     Lab of Plasma Studies	
     369 Upson Hall			phone: 607 255 7267
     Cornell University
     Ithaca, N.Y. 14853

-----------[000050][next][prev][last][first]----------------------------------------------------
Date:      Fri, 12-Sep-86 11:58:00 EDT
From:      Chartoff@DDN2.ARPA
To:        mod.protocols.tcp-ip
Subject:   DECNET


I am looking for interface products that would allow DECNET
communication across the Arpanet/Milnet or a public data network (PDN).

Has anyone had experience with such products and want to give advice?

Thanks

-----------[000051][next][prev][last][first]----------------------------------------------------
Date:      12 Sep 86 11:58 EDT
From:      Chartoff @ DDN2
To:        tcp-ip @ sri-nic.arpa
Cc:        Chartoff @ DDN2
Subject:   DECNET

I am looking for interface products that would allow DECNET
communication across the Arpanet/Milnet or a public data network (PDN).

Has anyone had experience with such products and want to give advice?

Thanks

-----------[000052][next][prev][last][first]----------------------------------------------------
Date:      Fri, 12-Sep-86 12:19:57 EDT
From:      PHIL@UIUCVMD.BITNET (Phil Howard)
To:        mod.protocols.tcp-ip
Subject:   Tabs every 8 positions

Gee, even IBM has acknowledged that tabs belong on every 8 positions.
In VM/SP/CMS's XEDIT is the EXPAND subcommand that expands out the tabs
to proper positions.  There is also COMPRESS with puts tabs in, and in
the proper place.  I use these commands to handle files received from
non-IBM systems with tabs.  Everything has worked out fine.  Now I just
need a way to get square brackets on my IBM 3178 keyboard.

-----------[000053][next][prev][last][first]----------------------------------------------------
Date:      Fri, 12-Sep-86 12:48:21 EDT
From:      cetron@UTAH-CS.ARPA (Edward J Cetron)
To:        mod.protocols.tcp-ip
Subject:   Re: DELNI characteristics


	David Roode writes:

>It is also against the rules to plug one DELNI into another one
>unless that DELNI is NOT connected to an Ether[net].

WRONG!!!!!!!!!!!!!!!!  Nowhere does it say that one DELNI cannot be
cascaded to another ethernet connected DELNI! And I've check every manual,
tech and sales, Digital has produced....

	The above is a very common misconception...the real configuration
rule has to do with the fact the propagation delays build through the
ethernet having to do with things like cable lengths, numbers of repeaters
etc....

	The one rule that is most apropos is the 'no more than two repeaters
between any two nodes....'  This is (among other things) to prevent the
propagation delay between any two nodes to be less than the max... For very
conservative purposes, the DELNI acts with a propagation delay of 1 repeater
and this sort of implies the above misconception.

	In reality: 
	1. A DELNI actually appears to introduce the delay of about .6-.7 that
of a repeater.
	2. I have seen systems with 2, 3, and 4 cascaded DELNI's that work and
DO  maintain in-spec propagation delays.
	3. It has been pointed out that with the appropriate configuration, one
could even make 4 repeaters in a row work.
	4. The configuration rules (like the rs232 max line length rules) are
very conservative to allow 100% probability of a network working when they are
strictly adhered to.  This means that quite often, for networks not in a very
critical area (i.e. hospital ICU's controlling patient therapy) they are only
to be considered guidelines BY PEOPLE WHO UNDERSTAND WHY THE RULES ARE THERE.
Rules are there for a reason, but should be tested and verified before blindly
obeying them without knowing why

-ed cetron
Center for Engineering Design
Univ of Utah
cetron%utah-cbd@utah-cs.arpa

-----------[000054][next][prev][last][first]----------------------------------------------------
Date:      Fri, 12-Sep-86 12:49:01 EDT
From:      root@BU-CS.BU.EDU (Ra)
To:        mod.protocols.tcp-ip
Subject:   Re: Formatting Query

To add my 2c:

1. I am not sure about the definition of "commonly used" but
IBM Mainframes (EBCDIC) generally do not interpret tabs the
way full-duplex systems use them (not that you can't simulate
them, but it tends to be more variable in interpretation, if
at all, software application dependant.)

2. Sending files through mail via heterogenous systems is fraught
with peril although it usually works well enough if it's just text
meant to be used as text (eg. a fortran program with embedded tabs
may not compile at all when sent to an IBM system, I don't remember
for sure, but I wouldn't be in the slightest bit shocked, and fixing
it wouldn't take that much sophistication on the part of the user.)

A solution is the UUENCODE/UUDECODE program distributed with UNIX
(there are public domain versions) which encodes files in a very
conservative way (more or less 026 character subset, 40 chars/line.)
For example, I have a version of it running on our IBM mainframe and
it seems to work, particularly for cases as above (yes, I expand
tabs to every eight, perhaps that should be an option, but at least
it's all at the user level rather than a decision made by the SMTP daemon.)

Obviously with binary files there's not much you can do, but you
could pass one THROUGH an incompatible system with little risk of
problems using an encoding, hey, caveat usor.)

In re SMTP, I would vote conservative, change nothing unless you
have a good reason to (eg. ASCII->EBCDIC, there is an EBCDIC tab
character.) It should be easy enough to provide software to do
minor conversions once the the file has arrived (if it is intact,
expanding tabs for example discards information which seems to
violate some basic principle of design.)

	-Barry Shein, Boston University

-----------[000055][next][prev][last][first]----------------------------------------------------
Date:      Fri, 12-Sep-86 16:49:00 EDT
From:      Kevin_Crowston@XV.MIT.EDU
To:        mod.protocols.tcp-ip
Subject:   Re: Formatting Query

Just to add to the confusion...

My system (a Xerox Star) displays mail in a proportionally spaced font,
making all diagrams hard to read without changing the font.
I'm not sure if this is a bug or a feature, however.

In general, I think that having the mailer expand the tabs would be a bad
idea.  There might be reasons for wanting the tabs in the message and it shouldn't
be impossible to do this.  The user mail agent might do that sort of processing
by default, however.  For example, if I try to send a message that includes
font changes, etc. the mailer asks if I really want to send formatted text,
and strips the formatting if I don't.

Kevin Crowston
MIT Sloan School of Management

kevin@xv.mit.edu

-----------[000056][next][prev][last][first]----------------------------------------------------
Date:      13 Sep 1986 18:37-PDT
From:      STJOHNS@SRI-NIC.ARPA
To:        jtw@MITRE-BEDFORD.ARPA
Cc:        tcp-ip@SRI-NIC.ARPA, sra@MITRE-BEDFORD.ARPA tgw@MITRE-BEDFORD.ARPA
Subject:   Re: RFC 912, Auth Service
Speaking as the author of rfc912 (actually, see rfc931 which is a
revised version of 912) I know of no one who currently implements
it.   I  did  a  test  implementation of it for Multics and did a
little playing with implementing the services  end  of  it  (i.e.
TELNET  without  having to explicitly login), but that version is
lost to obscurity.  Mike
-----------[000057][next][prev][last][first]----------------------------------------------------
Date:      Sat, 13-Sep-86 16:56:42 EDT
From:      PALLAS@SUSHI.STANFORD.EDU (Joseph I. Pallas)
To:        mod.protocols.tcp-ip
Subject:   Re: Formatting Query

RFC821 says:
            The mail data may contain any of the 128 ASCII character
            codes.

This clearly makes it illegal for SMTP mailers to expand tabs.  On the
other hand, RFC822 says:

        Writers of  mail-sending  (i.e.,  header-generating)  programs
        should realize that there is no network-wide definition of the
        effect of ASCII HT (horizontal-tab) characters on the  appear-
        ance  of  text  at another network host; therefore, the use of
        tabs in message headers, though permitted, is discouraged.

This clearly suggests that mail-agents expand tabs before submitting
them to mailers.

Meanwhile, if you use tabs in formatting such that the width of a tab
stop affects the content of your message (e.g., in drawing pictures),
other people will get what you deserve.

joe
-------

-----------[000058][next][prev][last][first]----------------------------------------------------
Date:      Sun, 14-Sep-86 12:21:56 EDT
From:      hedrick@topaz.rutgers.edu (Charles Hedrick)
To:        mod.protocols.tcp-ip
Subject:   Re: RFC 912, Auth Service

We implemented RFC 912 on our DEC-20's.  Our DEC-20 FTP supports
the equivalent of Unix's .rhosts file, and uses auth service
to verify that the guy at the other end is really who he claims
to be.  I regard this is slightly more secure than the mechanism
used by rcp.

-----------[000059][next][prev][last][first]----------------------------------------------------
Date:      Mon, 15 Sep 86 08:05:48 MDT
From:      ncc!lyndon%ALBERTA%UQV-MTS%UMich-MTS.Mailnet@MIT-MULTICS.ARPA
To:        tcp-ip@SRI-NIC.ARPA,    sri-nic.arpa!tcp-ip@ALBERTA
From: lyndon@ncc.UUCP (Lyndon Nerenberg)
Newsgroups: net.video,mod.protocols.tcp-ip
Subject: Re: Ethernet between buildings
Message-ID: <722@ncc.UUCP>
Date: Sat, 13-Sep-86 19:32:57 MDT
References: <611.rbbb.titan@Rice>
Organization: Nexus Computing Corp.,  Edmonton, AB
Lines: 35
Summary: Not a wives tale!

I am cross-posting as this sort of relates to the discussion in
mod.protocols.tcp-ip about grounding ethernet cables...

In article <611.rbbb.titan@Rice>, rbbb@rice.edu (David Chase) writes:
>    ...     A sort of old wives tale of lightning protection says that you
> should put a tight loop in a wire near a good ground; the lightning sees
> that as a great big inductor, and hops over to the good ground.
>
> David

The "signal" introduced into a cable by a lightning strike consists of
extremely high frequency radiation. It does not take much inductance to
throw up a "brick wall" to it. Many television stations run their feeds
through a single loop at the base of the tower, then to the transmitter
shack. The RF from a lightning strike will (hopefully :-) take the easier
path from the feed line, through the base of the tower, to ground.

I handled the transmitter plant installation and setup for a local FM BCST
station a couple of years back. The antenna was located on top of a
building at the University. We were unable to properly ground the tower,
so we threw up a loop inside the roof house for the elevators ( *lots*
of metal in there :-)

I know a number of amateur radio op's in town who do the same thing - 2
turns of the feedline at the base (approx. 3 feet in diameter) before
entering the house. I can't say that any of them have been hit, so I won't
guarantee results. Then again, I have watched local TV broadcast towers take
direct hits without going off the air.

I'm sure a posting to net.ham-radio would provide some further information
on practical experiences of dealing with lightning hits.
--

Lyndon Nerenberg (VE6BBM)                 {ihnp4,ubc-vision}!alberta!ncc!lyndon
Systems Group - A Div. of Nexus Computing Corp.                 Envoy_100: Unix

-----------[000060][next][prev][last][first]----------------------------------------------------
Date:      Mon, 15-Sep-86 08:37:18 EDT
From:      mckenzie@j.bbn.com (Alex McKenzie)
To:        mod.protocols.tcp-ip
Subject:   Ethernet Multiplexors

We have had various troubles attaching hosts to our BBN Ethernet using DELNIs.
We haven't actually tried too hard to diagnose them all - simply noted that
there are hosts which don't work when connected to a DELNI.  We assume that DEC
has probably "improved" or ignored some part of the host to transceiver
protocol.  We are now using large quantities of an Ethernet multiplexor made by
TCL, Inc., 41829 Albrae St., Fremont, CA 94538 (415/657-3800).  You buy a
chassis with 9 card slots.  You buy a "downstream" card and 1 to 8 "upstream"
cards.  Each upstream card can be either V1 or 802.3; I think this is also true
of the downstream card but I'm not so sure.  As I recall, a box with a
downstream card costs about $400 and each upstream card costs about $100.  We
have had no troubles with these multiplexors, have successfully cascaded them,
and I know of no hosts that can't use them.

Regards,
Alex McKenzie

-----------[000061][next][prev][last][first]----------------------------------------------------
Date:      Mon, 15 Sep 86 8:37:18 EDT
From:      Alex McKenzie <mckenzie@j.bbn.com>
To:        tcp-ip@sri-nic.arpa
Subject:   Ethernet Multiplexors
We have had various troubles attaching hosts to our BBN Ethernet using DELNIs.
We haven't actually tried too hard to diagnose them all - simply noted that
there are hosts which don't work when connected to a DELNI.  We assume that DEC
has probably "improved" or ignored some part of the host to transceiver
protocol.  We are now using large quantities of an Ethernet multiplexor made by
TCL, Inc., 41829 Albrae St., Fremont, CA 94538 (415/657-3800).  You buy a
chassis with 9 card slots.  You buy a "downstream" card and 1 to 8 "upstream"
cards.  Each upstream card can be either V1 or 802.3; I think this is also true
of the downstream card but I'm not so sure.  As I recall, a box with a
downstream card costs about $400 and each upstream card costs about $100.  We
have had no troubles with these multiplexors, have successfully cascaded them,
and I know of no hosts that can't use them.

Regards,
Alex McKenzie

-----------[000062][next][prev][last][first]----------------------------------------------------
Date:      Mon, 15-Sep-86 10:05:48 EDT
From:      lyndon%ALBERTA%UQV-MTS%UMich-MTS.MAILNET@ncc.UUCP
To:        mod.protocols.tcp-ip
Subject:   (none)

From: lyndon@ncc.UUCP (Lyndon Nerenberg)
Newsgroups: net.video,mod.protocols.tcp-ip
Subject: Re: Ethernet between buildings
Message-ID: <722@ncc.UUCP>
Date: Sat, 13-Sep-86 19:32:57 MDT
References: <611.rbbb.titan@Rice>
Organization: Nexus Computing Corp.,  Edmonton, AB
Lines: 35
Summary: Not a wives tale!

I am cross-posting as this sort of relates to the discussion in
mod.protocols.tcp-ip about grounding ethernet cables...

In article <611.rbbb.titan@Rice>, rbbb@rice.edu (David Chase) writes:
>    ...     A sort of old wives tale of lightning protection says that you
> should put a tight loop in a wire near a good ground; the lightning sees
> that as a great big inductor, and hops over to the good ground.
>
> David

The "signal" introduced into a cable by a lightning strike consists of
extremely high frequency radiation. It does not take much inductance to
throw up a "brick wall" to it. Many television stations run their feeds
through a single loop at the base of the tower, then to the transmitter
shack. The RF from a lightning strike will (hopefully :-) take the easier
path from the feed line, through the base of the tower, to ground.

I handled the transmitter plant installation and setup for a local FM BCST
station a couple of years back. The antenna was located on top of a
building at the University. We were unable to properly ground the tower,
so we threw up a loop inside the roof house for the elevators ( *lots*
of metal in there :-)

I know a number of amateur radio op's in town who do the same thing - 2
turns of the feedline at the base (approx. 3 feet in diameter) before
entering the house. I can't say that any of them have been hit, so I won't
guarantee results. Then again, I have watched local TV broadcast towers take
direct hits without going off the air.

I'm sure a posting to net.ham-radio would provide some further information
on practical experiences of dealing with lightning hits.
--

Lyndon Nerenberg (VE6BBM)                 {ihnp4,ubc-vision}!alberta!ncc!lyndon
Systems Group - A Div. of Nexus Computing Corp.                 Envoy_100: Unix

-----------[000063][next][prev][last][first]----------------------------------------------------
Date:      Mon, 15-Sep-86 17:19:27 EDT
From:      mckee@MITRE.ARPA
To:        mod.protocols.tcp-ip
Subject:   TCP/IP Conformance Testing


The following article was published in NETWORK WORLD, by Paul
Korzeniowski, 1 Sept. 86, pg 2.

Monterey, Calif. - Corporation for Open Systems (COS) supporters beware.
Ensuring that devices on a multivendor network really can work together
has proven to be a task too complex even for Uncle Sam.
    Last week at the first Transmission Control Protocol/Internet
Protocol (TCP/IP) Vendor Workshop ("TCP/IP future at stake," Network
World, Aug. 25), the U.S. Defense Communications Agency announced it is
washing its hands of TCP/IP conformance testing.
    The agency oversees transmission facilities that link government
agencies, universities, and corporations into one giant network of
networks.  The umbrella network grew out of the Advanced Research
Projects Agency Network (Arpanet), designed in the late 1960s as the
world's first packet-switching net.
    The original network has expanded so that today it supports more
than 30,000 computer systems ranging in size from Cray Research, Inc.'s
supercomputers to Apple Computer, Inc.'s Macintoshes.
    For the last few years, DCA and a number of other government
agencies have been developing test suites and creating a center for
TCP/IP conformance.  The work was similar to that undertaken by COS,
which will handle Open Systems Interconnect (OSI) conformance testing
and the development to test suites.  At the workshop, two government
officials told attendees that plans for the center had been dropped.
    The DCA has developed and continues to design conformance test
criteria, but they are not robust enough to ensure that all TCP/IP
products can interoperate.  "There have been instances where vendors
have spent a lot of time and money trying to ensure their products would
perform on the government network," said Daniel Lynch, president of
Advanced Computing Environments in Cupertino, Calif.  "When their
product was linked to another company's product, they couldn't
communicate."
    Government officials declined to discuss the decision.  But
conference attendees speculated the government found the task of
supplying comprehensive conformance tests nearly an impossible one.
    One problem testers faced is that the only way to test a product
properly is to attach it to the target network, a procedure that the
DCA would not condone.  Also, running a testing center requires a great
deal of money and engineering talent.  Lynch said only a handful of
engineers are qualified to develop and run conformance tests.
    The DCA decision leaves TCP/IP vendors with a number of unappealing
options.  They could form a COS-like organization.  But the consensus
seemed to be that fewer rather than more of such standards organizations
are needed.
    Individual companies could develop their own testing procedures.
But the resources required for such self-testing could limit the number
of vendors able to bring TCP/IP products to market.  Attendees formed a
task force to explore how vendors should proceed.

-----------[000064][next][prev][last][first]----------------------------------------------------
Date:      Mon, 15-Sep-86 17:23:12 EDT
From:      cetron@UTAH-CS.ARPA (Edward J Cetron)
To:        mod.protocols.tcp-ip
Subject:   Ultrix 1.2 and unacceptable tcp packets

After hacking with the Tek tcp/ip package to add keep-alive (or probe-alive
as the case may be) support, I found the following behaviour from two Ultrix
sites:

	line sits idle for x length of time (so snd.nxt = snd.una = Ultrix
		rcv.nxt...)
	Tek tcp/ip sends a packet designed to be unacceptable in order to force
		a response (as documented in the mil-std and rfc for tcp). This
		packet has   seg.seq = snd.nxt-1   and   seg.ack = rcv.nxt-1
		which is obviously unacceptable and should force and ack with
		the proper counters.

	The Ultrix site receives the packet, and promptly drops it off of the
		face of the earth (though apparently reading the code it does
		use it to update the window...)

Am I missing something or is this indeed non-compliant?  All of the 4.2bsd and
4.3 bsd sites handle this fine...  I know what is different between the 4.3bsd
and the Ultrix code but before I fix it myself, I want to be sure I haven't 
overlooked something and/or that other Ultrix sites have noticed this same 
problem....

		thanx

			ed

cetron%utah-cbd@utah-cs.arpa

-----------[000065][next][prev][last][first]----------------------------------------------------
Date:      Mon, 15-Sep-86 18:49:31 EDT
From:      leong@ANDREW.CMU.EDU (John Leong)
To:        mod.protocols.tcp-ip
Subject:   Re: DELNI characteristics


On the subject of cascading DELNI, one has to be careful about one quirk. 

The Intel 82586 chip has, by default, a check that is not really in
conformance of the Ethernet spec. It measures the time between transmit and
receiving the signal back from the transceiver and signals whether the round
trip time equates roughly to 50 meter of drop cable (nothing to do with the
Ethernet slot time of 51.2 micro seconds or roughly 2.5Km). This test is
quite bogus but some earlier version of DECNET software actually check for
that return code and declares the world is sick accordingly. We have ran into
that problem earlier on when we cascaded DELNI's since they introduced
roughly 10 meter of cable worth of delay and we ran over the 50 meters.

-----------[000066][next][prev][last][first]----------------------------------------------------
Date:      Tue, 16-Sep-86 05:36:52 EDT
From:      ROODE%BIONET@SUMEX-AIM.STANFORD.EDU (David Roode)
To:        mod.protocols.tcp-ip
Subject:   Re: DELNI characteristics

Reference on DELNI limitation to non-cascaded mode when connected
to an Ether cable:


EK-ETHV1-IN-002 Ethernet Installation Guide, Digital Equipment Corporation,
1984, Appendix E, p. E1:

"If DELNI interconnects are cascaded, the top DELNI interconnect
cannot connect to an Ethernet coaxial cable.  A maximum of two layers
of DELNI interconnects are permitted, with the second layer of
DELNI interconnects operating in the global mode."
-------

-----------[000067][next][prev][last][first]----------------------------------------------------
Date:      Tue, 16-Sep-86 08:57:16 EDT
From:      swb@DEVVAX.TN.CORNELL.EDU (Scott Brim)
To:        mod.protocols.tcp-ip
Subject:   DELNI characteristics


   Date: Mon, 15 Sep 86 18:49:31 edt
   From: leong@andrew.cmu.edu (John Leong)

   .....
   The Intel 82586 chip has, by default, a check that is not really in
   conformance of the Ethernet spec. It measures the time between transmit and
   receiving the signal back from the transceiver and signals whether the round
   trip time equates roughly to 50 meter of drop cable (nothing to do with the
   Ethernet slot time of 51.2 micro seconds or roughly 2.5Km). This test is
   quite bogus ....

You can tell the chip to disable that feature.  I think it's *on* at
power-up.  Gould used to use the round-trip-to-transceiver check; we
asked them to disable it and I believe it's now off for all new Gould
ethernet boards.
								Scott

-----------[000068][next][prev][last][first]----------------------------------------------------
Date:      Tue, 16-Sep-86 10:56:00 EDT
From:      DCP@QUABBIN.SCRC.Symbolics.COM (David C. Plummer)
To:        mod.protocols.tcp-ip
Subject:   Re: Formatting Query

Tabs should be expanded at the source; not by any heuristic in some
program that has no chance of guessing right.  This is preferably the
user's mail composition program, perhaps by a user profile switch, but
it should not be done by the SMTP user side, or the SMTP sending side,
or any other mail delivery program (SMTP isn't the only one that exists
(surprise!!)).  If the user's composition program doesn't have this
feature, then the user should do the conversion if tabs are significant.

You simply cannot send data from one place to the other unless you
/know/ that both sides agree on how to interpret the characters.  I
believe the /only/ set of characters we all agree on are the 95 ascii
characters space through tilde, plus NVT newline.  I would have
italicized /know/ but only other Lisp Machines would be able to see it
without garbage characters...

-----------[000069][next][prev][last][first]----------------------------------------------------
Date:      Tue, 16-Sep-86 11:34:00 EDT
From:      Ata@RADC-MULTICS.ARPA ("John G. Ata")
To:        mod.protocols.tcp-ip
Subject:   Re: Formatting Query


Yes, you are correct...when I said SMTP mailer, I meant the mail
composition program that submits mail to the SMTP mailer.  Sorry for the
confusion.  I strongly believe that mail composition programs, should
for the most part, expand tabs to spaces unless overridden by another
command or control argument.  This is because, in the vast majority of
cases, tabs are used to merely position the next character in a
particular column, so that tab expanding is then the right thing to do
given that there isn't a standard definition of tabstops over the
network.  Of course, for those cases where tabs mean something else, the
user can override this, perhaps with a command/control argument.  The
bottom line is that, in most cases, tabs will be vastly reduced in SMTP
message text.
          As a matter of record, the standard Multics mail system does
not allow tabs at all whether local or network.  Therefore, the mail
program will expand tabs BEFORE submitting to the SMTP mailer, just like
it will expand before submission into another local mailbox.  Given that
tab characters are not allowed in messages, the server SMTP does also
expand tabs to maintain compatability with the rest of the mail system.

                    John G. Ata

-----------[000070][next][prev][last][first]----------------------------------------------------
Date:      Tue, 16-Sep-86 12:18:40 EDT
From:      alexp@xios.XIOS.CA (Alex Pepple)
To:        mod.protocols.tcp-ip
Subject:   X.25 Board Inquiry

*** BUGS SPRAY ***

I'm looking for X.25 boards (Full X.25) for Multibus and VMEbus machines
to interface to tcp-ip and other protocols. Would anyone have a list of
companies offering QUALITY products of that nature?
Please reply directly to me. Sufficient Interest = Net Summary.

I'm waiting in anticipation for E-mail bits of your brainwaves! -:)

-- Alex
 
...The bitterness of POOR QUALITY is remembered long after the
     sweetness of LOW PRICE is forgotten.  

-----------[000071][next][prev][last][first]----------------------------------------------------
Date:      Tue, 16-Sep-86 17:10:37 EDT
From:      louie@TRANTOR.UMD.EDU (Louis A. Mamakos)
To:        mod.protocols.tcp-ip
Subject:   Ultrix 1.2 and unacceptable tcp packets

I've noticed other TCP problems with Ultrix 1.2's TCP.  After we installed
ULTRIX on a MicroVAX system, we don't seem to be able to send mail to our
Sperry 1100 system anymore.  The connection just hangs after a bit.  This
concerned me greatly, being one of the authors of the TCP/IP software on
the Sperry host.  None of our other systems had any problems, (2.9BSD UNIX,
4.2 BSD UNIX, Wollongong VMS, FUZZBALL, *Ultrix 1.1*).  Examination of
trace data on the Sperry indicates that it's just waiting for more data
on the SMTP connection after sending a window update.

(Flame on)
Our solution?  Very simple.  Trash Ultrix and run 4.3 BSD.  Not only has
DEC managed not to fix broken code, but they've even broken working code!

I'll just bet DECNET works though.
(Flame off)

Louis A. Mamakos  WA3YMH    Internet: louie@TRANTOR.UMD.EDU
University of Maryland, Computer Science Center - Systems Programming

-----------[000072][next][prev][last][first]----------------------------------------------------
Date:      Fri, 19-Sep-86 09:32:26 EDT
From:      mrose@NRTC-GREMLIN.ARPA (Marshall Rose)
To:        mod.protocols.tcp-ip
Subject:   A new discussion group


    I am pleased to announce the charter of a new discussion group.


                         ISODE@NRTC.NORTHROP.COM

    ISODE is a discussion group which focuses on the ISO Development
    Environment, an openly available implementation of some of the
    higher-level protocols adopted by international organizations (ISO,
    CCITT, ECMA).  These implementations are hosted on top of TCP/IP
    using the method discussed in RFC983.  Appropriate topics are:  

        - questions about how to use ISODE (and announcements of ports to
          other target environments)

        - discussion of ISODE as a part of a TCP/IP to ISO migration strategy

        - exchange of ideas regarding ISO-based applications running in
          a native TCP/IP environment

	- debate regarding where ISODE should go next

    This list naturally has some overlap with the TCP-IP list, the ISO
    list, and so on.  Contributors are urged to use the appropriate list
    based on their topic of discussion.  If there is sufficient demand,
    new sublists may be formed.  

    All requests to be added to or deleted from this list, along with
    problems, questions and suggestions, should be sent to
    ISODE-Request@NRTC.NORTHROP.COM.

    Coordinator: Marshall T. Rose (MTR) <Bug-ISODE@NRTC.NORTHROP.COM>

-----------[000073][next][prev][last][first]----------------------------------------------------
Date:      Fri, 19-Sep-86 19:09:33 EDT
From:      braden@VENERA.ISI.EDU (Bob Braden)
To:        mod.protocols.tcp-ip
Subject:   Internet Multicasting for NETBIOS


I would like to comment on the use of Internet multicasting for the
implementation of NETBIOS over the DoD protocol suite.

Both of the proposed protocols for implementing NETBIOS quite properly
restrict the use of NETBIOS broadcast packets to the same local network.
This restriction is necessary because the Internet architecure has not
provided a reasonable Internet-wide broadcast/multicast mechanism.

However,  I believe that this can be only a temporary restriction. 
There is a clear need to extend the Internet architecture to provide a
multicasting mechanism, and in fact the NETBIOS application is an
excellent example of the requirement for "distributed binding" which 
multicasting can provide. 

There is active work on the development and experimental deployment of a
Internet multicasting facility, as described in RFC 966 and RFC988.
Since (as we proudly proclaim) our work is characterized by trying out
something new before writing a standards document, the multicasting
extension to the Internet architecture described in these RFC's is not
yet in the "proposed standard" stage, although we are moving in that
direction.  Experimental implementations are now under development.

What are the implications for the NETBIOS protocol design effort?

**> Make sure your protocol is consistent with the proposed Internet
    multicasting facility, so that the local-net-only restriction on
    broadcasting can be removed from a NETBIOS implementation with
    minimal work when and if Internet multicasting is generally
    available.

At some point, the NETBIOS application could be a good demonstration of
the Internet multicasting facility.  The vendors developing NETBIOS
implementations for the DoD protocol suite are concerned with making a
product and selling it, rather than in protocol development.  However,
if NETBIOS is successful, perhaps customer interest in removing the
broadcast restriction will bring about a more active collaboration
between vendors and researchers interested in Internet multicasting.

Bob Braden

  
  

-----------[000074][next][prev][last][first]----------------------------------------------------
Date:      Sat 20 Sep 86 15:16:34-PDT
From:      "Henry Dardy" <dardy@nrl-acoustics>
To:        "tcp-ip" <tcp-ip@sri-nic.arpa>
Cc:        dardy
Subject:   RE: Ultrix 1.2 and unacceptable tcp packets
You are right: Decnet works perfectly! ***Cough, ghasp, wheeze***.  Sorry,
but your (flame on) hadn't cooled yet!

Hank

------
-----------[000075][next][prev][last][first]----------------------------------------------------
Date:      Sun, 21-Sep-86 14:17:56 EDT
From:      tcs@USNA.ARPA (Terry Slattery)
To:        mod.protocols.tcp-ip
Subject:   Fiber Ethernet problem

We have a fiber optic based Ethernet product installed here and are
having a problem with a Gould 9050 being attached to the net.

DESCRIPTION:

We have the Codenoll ethernet on fiber optic product with the following
configuration:

-----------  ~325M    --------------    ~800M       ---------------
|usna.arpa|-----------|Star Coupler|----------------|usna-gus.arpa|
-----------           --------------                ---------------
                            |     
                            | ~75M
                            |
                      ---------------
                      |usna-cs1.arpa|
                      ---------------
M = meters

Both usna.arpa and usna-cs1.arpa can communicate.  Usna-gus.arpa can hear
some (most?) rwho packets from usna and cs1.  Gus cannot send anything
out without error.  A Gould 6050 which is co-located with usna can
communicate over the 325 meter segment without problems.

ANALYSIS:

Optical power measurements show -15db at usna and -12db at gus (better
polished connectors and lower loss cable are the difference).  The
flux budget is 21db, so we are well within spec there.

A recent note to these lists leads me to believe that there is a timing
problem.  Codenoll supplied the following timing info:

Device					Delay (ns)
Controller encoder			  100
Xcvr xmit				  300
Fiber cable (1600 meters@4.33ns/m)	 6928
Xcvr rcv				  650
Xcvr cable (60 meters@5.13ns/m)		  308
					-----
TOTAL					 8386

I have connected the Gould and a Tektronix 6130 to a TCL MP station
and they communicate without problems, thus proving that the interface
is working correctly.

MISC. INFO:

The Gould Ethernet Controller Model 8561 Tech. Manual (May 85)
says that it tries 16 retransmits before giving up completely.
It also mentions a control bit described as:
  "Transmit even if no arrrier sense signal is detected."
The driver doesn't include any code to modify this bit; it
is automatically reset upon board power-up.

QUESTIONS:

Is the timing out of spec with respect to what the Gould ethernet
interface is capable of handling?

What time delay does most equipment expect?

Does anyone else have experience with this or Siecor's product over
the distances involved here?

Are there more details available on what Gould did w.r.t. the problem
reported at Perdue?
	

Please respond directly and I will summarize the responses.  Thanks,
	-tcs
	Terry Slattery	  U.S. Naval Academy	301-267-4413
	ARPA: tcs@usna.arpa
	UUCP: decvax!brl-smoke!usna!tcs

-----------[000076][next][prev][last][first]----------------------------------------------------
Date:      Sun, 21 Sep 86 14:17:56 EDT
From:      Terry Slattery <tcs@USNA.ARPA>
To:        tcp-ip@SRI-NIC.ARPA
Cc:        gouldbugs@BRL.ARPA
Subject:   Fiber Ethernet problem
We have a fiber optic based Ethernet product installed here and are
having a problem with a Gould 9050 being attached to the net.

DESCRIPTION:

We have the Codenoll ethernet on fiber optic product with the following
configuration:

-----------  ~325M    --------------    ~800M       ---------------
|usna.arpa|-----------|Star Coupler|----------------|usna-gus.arpa|
-----------           --------------                ---------------
                            |     
                            | ~75M
                            |
                      ---------------
                      |usna-cs1.arpa|
                      ---------------
M = meters

Both usna.arpa and usna-cs1.arpa can communicate.  Usna-gus.arpa can hear
some (most?) rwho packets from usna and cs1.  Gus cannot send anything
out without error.  A Gould 6050 which is co-located with usna can
communicate over the 325 meter segment without problems.

ANALYSIS:

Optical power measurements show -15db at usna and -12db at gus (better
polished connectors and lower loss cable are the difference).  The
flux budget is 21db, so we are well within spec there.

A recent note to these lists leads me to believe that there is a timing
problem.  Codenoll supplied the following timing info:

Device					Delay (ns)
Controller encoder			  100
Xcvr xmit				  300
Fiber cable (1600 meters@4.33ns/m)	 6928
Xcvr rcv				  650
Xcvr cable (60 meters@5.13ns/m)		  308
					-----
TOTAL					 8386

I have connected the Gould and a Tektronix 6130 to a TCL MP station
and they communicate without problems, thus proving that the interface
is working correctly.

MISC. INFO:

The Gould Ethernet Controller Model 8561 Tech. Manual (May 85)
says that it tries 16 retransmits before giving up completely.
It also mentions a control bit described as:
  "Transmit even if no arrrier sense signal is detected."
The driver doesn't include any code to modify this bit; it
is automatically reset upon board power-up.

QUESTIONS:

Is the timing out of spec with respect to what the Gould ethernet
interface is capable of handling?

What time delay does most equipment expect?

Does anyone else have experience with this or Siecor's product over
the distances involved here?

Are there more details available on what Gould did w.r.t. the problem
reported at Perdue?
	

Please respond directly and I will summarize the responses.  Thanks,
	-tcs
	Terry Slattery	  U.S. Naval Academy	301-267-4413
	ARPA: tcs@usna.arpa
	UUCP: decvax!brl-smoke!usna!tcs
-----------[000077][next][prev][last][first]----------------------------------------------------
Date:      Sun, 21-Sep-86 14:50:03 EDT
From:      dardy@NRL-ACOUSTICS.ARPA ("Henry Dardy")
To:        mod.protocols.tcp-ip
Subject:   RE: Ultrix 1.2 and unacceptable tcp packets

You are right: Decnet works perfectly! ***Cough, ghasp, wheeze***.  Sorry,
but your (flame on) hadn't cooled yet!

Hank

------

-----------[000078][next][prev][last][first]----------------------------------------------------
Date:      22 Sep 86 11:19:00 PST
From:      <gary@acc.arpa>
To:        "tcp-ip" <tcp-ip@sri-nic>
Subject:   Standard X.25 on Arpanet
Hans,

I would be extremely interested in what you find out.  As it would be
germane for this group, could you please publish your findings?

Thanks,

Gary
.

------
-----------[000079][next][prev][last][first]----------------------------------------------------
Date:      Mon, 22-Sep-86 10:43:47 EDT
From:      hwb@MCR.UMICH.EDU (Hans-Werner Braun)
To:        mod.protocols.tcp-ip
Subject:   Standard X.25 on the Arpanet.

Hi:
 
I am wondering about who is using Standard X.25 to connect to an Arpa IMP
(PSN) these days. Not HDH, not DH or LH (no 1822 at all), no Basic X.25
and not on the Milnet. Just plain Arpanet Standard X.25 attachments. I
would appreciate a note if you are connected like that and would also be
interested in what machine/operating_system/interface you use and
eventually whether you saw any problems with such a setup.
 
	-- Hans-Werner

-----------[000080][next][prev][last][first]----------------------------------------------------
Date:      Mon, 22-Sep-86 12:00:51 EDT
From:      mckee@MITRE.ARPA
To:        mod.protocols.tcp-ip
Subject:   Comm. Fault Recognition/Diagnosis

For those of you interested in communications network fault
recognition and diagnosis, the 15 Sept. issue of Datamation has
a survey article by Bill Musgrave;  "Sorting Out The Solutions",
page 98.

H. Craig McKee

-----------[000081][next][prev][last][first]----------------------------------------------------
Date:      Mon, 22-Sep-86 15:19:00 EDT
From:      gary@acc.arpa
To:        mod.protocols.tcp-ip
Subject:   Standard X.25 on Arpanet

Hans,

I would be extremely interested in what you find out.  As it would be
germane for this group, could you please publish your findings?

Thanks,

Gary
.

------

-----------[000082][next][prev][last][first]----------------------------------------------------
Date:      Mon, 22-Sep-86 22:06:51 EDT
From:      rms@ACC-SB-UNIX.ARPA (Ron Stoughton)
To:        mod.protocols.tcp-ip
Subject:   X.25 on Arpanet

Hosts requiring X.25 Standard service must be connected to an IMP running
PSN6.  I am not certain, but I don't believe many (if any at all) Arpanet
IMPs have been converted to run PSN6.  Many will require a hardware upgrade
(C/30 to C/30E).  Maybe someone from BBN can comment on this and give a
schedule for upgrading the Arpanet IMPs.

Ron Stoughton
rms@acc-sb-unix.arpa

-----------[000083][next][prev][last][first]----------------------------------------------------
Date:      23 Sep 1986 05:53-PDT
From:      STJOHNS@SRI-NIC.ARPA
To:        rms@ACC-SB-UNIX.ARPA
Cc:        tcp-ip@SRI-NIC.ARPA, gary@BRL-SAGE.ARPA
Subject:   Re: X.25 on Arpanet
As  of  this  writing and speaking semi-authoritatively I believe
that all of the PSNs on the ARPANET have been upgraded  to  C30E.
I  am  not  sure of the status of the PSN software though on that
side of the net, but the plan was to field PSN 6  as  quickly  as
possible.

Mike StJohns (DDN PMO)
-----------[000084][next][prev][last][first]----------------------------------------------------
Date:      Tue, 23-Sep-86 10:15:08 EDT
From:      jseeger@CC5.BBN.COM
To:        mod.protocols.tcp-ip
Subject:   Re: X.25 on Arpanet

All,

ARPANET nodes have been upgraded hardware-wise to C/30e's.  The upgrade to 
PSN 6.0 software is proceeding now.  However, all nodes have been running
PSN 5.0 for several months, and x.25 standard service was even possible
before that, under PSN 3.0/4.0 (although it required the loading of a
separate x.25 package).

-Josh Seeger (BBN Communications, Network Analysis)

-----------[000085][next][prev][last][first]----------------------------------------------------
Date:      Tue, 23-Sep-86 12:50:17 EDT
From:      fserr@CC5.BBN.COM (Frederick E Serr BBN 3/176 x2474)
To:        mod.protocols.tcp-ip
Subject:   re: X.25 on ARPANET

The hardware upgrade on the ARPANET is complete.  PSN 6 has been
deployed to a few nodes, and deployment to other nodes in ongoing.
I am not certain if a definite schedule has been established for
the remaining nodes, but I would expect that all ARPANET nodes would
be running PSN 6 within one month.

Fred Serr
BBNCC Network Analysis

-----------[000086][next][prev][last][first]----------------------------------------------------
Date:      23 Sep 86 12:50:17 EDT (Tue)
From:      Frederick E Serr BBN 3/176 x2474 <fserr@cc5.bbn.com>
To:        hwb@mcr.umich.edu
Cc:        tcp-ip@sri-nic.ARPA
Subject:   re: X.25 on ARPANET
The hardware upgrade on the ARPANET is complete.  PSN 6 has been
deployed to a few nodes, and deployment to other nodes in ongoing.
I am not certain if a definite schedule has been established for
the remaining nodes, but I would expect that all ARPANET nodes would
be running PSN 6 within one month.

Fred Serr
BBNCC Network Analysis
-----------[000087][next][prev][last][first]----------------------------------------------------
Date:      Wed, 24-Sep-86 18:07:01 EDT
From:      tcs@USNA.ARPA (Terry Slattery)
To:        mod.protocols.tcp-ip
Subject:   Fiber Ethernet problem solved

The fiber ethernet problem has been solved.  This is rather long (~200
lines) and includes info supplied by various people on the net.  If you
only are interested in the solution, skip down to "THE SOLUTION".

First, a synopsis of the problem.

SYNOPSIS

A Gould 9050 connected via a Codenoll Ethernet over fiber optic network
wouldn't talk to a Vax 780 (or Gould 6050 co-located with the 780).  The
Goulds run thier UTX Unix product.  The fiber's optical power levels
checked out to be within spec.  The 9050 could hear rwho packets from
the 780. The 9050 would report errors on EVERY outgoing packet. Timing
estimates showed the 9050 getting receive carrier about 8us after
transmit started.  The controller manual noted a bit which when set
would:

  "Transmit even if no arrrier sense signal is detected."

but the driver didn't contain code to set the bit.  A recent note to
these lists from Cornell (I hope this is right this time) suggested that
the 9050 needed to have this bit set.

INPUT FROM OTHERS ON THESE LISTS

From: swb@devvax.tn.cornell.edu (Scott Brim)
I'm pretty sure I know what that bit is (haven't looked at the Gould
ethernet manual for a year) -- and I don't think it's your problem --
but here's an explanation of the bit: The Gould board uses the 82586
controller chip.  There's an option in the 82586 to look for its own
signal coming back from the transceiver within a certain amount of
time.  It used to be that you couldn't use a "transceiver cable" more
than a certain length (I remember 6 ns, but that seems awfully short).
They turned this off for us -- it's just a change to an initialization
bit in the PROMs on the Ethernet board.
							Scott

[Ed note: I didn't get any info from Gould on the actual time delay over
which the system would break, but our 6050 would work in place of the
780 and the time delay there was ~4us (calculated and measured).]

From:        <BEAME%MCMASTER.BITNET@WISCVM.WISC.EDU>
      Here at McMaster University we have a star coupler with 4 legs of
around 1500 ft. . We were using Codelink 2020A modems, we found that
we were able to transmit from leg 1 to leg (2,3,4) and leg 2 to leg (1,3,4)
we were unable to transmit from leg 3 to leg 4. This problem cleared up
after trying several modems on leg 4. Thus the matching of modems IS
important.

     Next, if you are using 2020A's, the echo from the modem (back down the
receive line while transmitting) is not done within the modem but at
the star coupler. Thus a machine might complain about late echo.

     We have just installed some 3030A's which do local echo and block out
the echo from the coupler and all of our problems an