[net.lan] DECNET - IP/TCP

allen@gitpyr.UUCP (P. Allen Jensen) (02/26/86)

Question:
   Can you have one set of systems running DECNET and another set
   running IP/TCP all on one DELNI without any special software/hardware ?

+-----------------------------------------------+
|              DECNET based systems             |
|     Only talk to other systems in this group  |
|          VAX/VMS 11/780 + 2 uVax II           |
+-----------------------------------------------+
                     |  |  |
                 +------------+
                 |   DELNI    |                           ???
                 +------------+
                    | | | | |
+-----------------------------------------------+
|              IP/TCP based systems             |
|     Only talk to other systems in this group  |
|              Apollo Masscomp Sun              |
+-----------------------------------------------+
-- 
        "It's quite easy, if you don't know how.
         That's the important bit.  Be not at all
         sure how you're doing it."
                                      -Arthur Dent


P. Allen Jensen
Manager, Systems Division
GTICES Systems Laboratory
Department of Civil Engineering
Georgia Insitute of Technology
Atlanta Georgia, 30332-0355
...!{akgua,allegra,amd,hplabs,ihnp4,masscomp,ut-ngp}!gatech!gitpyr!allen

tihor@acf4.UUCP (Stephen Tihor) (02/28/86)

It should work.

parker@epiwrl.UUCP (Alan Parker) (02/28/86)

Yes, you can run DECNET and TCP/IP on the same ethernet; and you can
use DELNIs with either DECNET or TCP/IP or both.      DELNIs don't
care at all about the protocol on the wire.   There are some ethernet
controllers out there that don't quite work with DELNIs however.   At
Naval Research Lab I had good luck using DELNIs with:

DEC DEUNA (of course) running both DECNET and TCP/IP
3Com Unibus controller
3Com Multibus controller (in a Sun and Imagen)
Interlan Unibus controller
Interlan QBus controller (in a Integrated Solutions)
DEC Qbus controller

We had trouble with the Excelan Qbus controller as shipped by
Integrated Solutions.   Excelan was made aware of the problem, but I
don't know if its been fixed (or even if its their fault).

ron@brl-smoke.ARPA (Ron Natalie <ron>) (03/04/86)

> Question:
>    Can you have one set of systems running DECNET and another set
>    running IP/TCP all on one DELNI without any special software/hardware ?
> 
Sure, as long as they don't want to talk to each other, you don't have
to change anything.  There is a field called the PROTOCOL address that
differentiates the different protcols in use.  The representative software
modules for the various protocols will either not see or reject packets
from the wrong protocol.  DECNET and IP use different numbers.

-Ron

jmg@cernvax.UUCP (jmg) (03/05/86)

In article <1474@brl-smoke.ARPA> ron@brl-smoke.UUCP writes:
>> Question:
>>    Can you have one set of systems running DECNET and another set
>>    running IP/TCP all on one DELNI without any special software/hardware ?
>> 
>Sure, as long as they don't want to talk to each other, you don't have
>to change anything.  There is a field called the PROTOCOL address that
>differentiates the different protcols in use.  The representative software
>modules for the various protocols will either not see or reject packets
>from the wrong protocol.  DECNET and IP use different numbers.
>
>-Ron
Don't forget that the ISO/IEEE version of Ethernet changes the protocol
ID field to be the LLC Data Unit count. DEC will be changing to this.
Any private use of the protocol ID field has to be agreed (with Xerox)
and has to be too large to be a possible LLCDU count. Software has to
be intelligent enough (!) to differentiate these cases.