[HECnet] "Poor mans routing" and the Italian Hobbyist DECNET

[Peter Coghlan]

The Cisco DECnet configuration guide can be found at:
http://www.cisco.com/en/US/docs/ios/decnet/configuration/guide/configuring_decnet.pdf


Thanks. I've downloaded it and had a look through it.


Let's assume the most usual conflict is at hand, where two different 
ogranisations use area 1, but neither the networks nor the areas can be 
merged, but the organisations need to communicate using DECnet.
Organisation A applies in the router the DECnet map for Organisation B 
where the B's real area 1 is chosen to have a virtual area of 24 (which 
is not used in either networks). Then B assignes a virtual area of 25 to 
the A's real area 1. Then they configure their routers to use DECnet map 
and the result looks like:

A			Cisco ATG				B

1.1 ----------------->	24.1 --------------------------------> 1.1
1.2 ----------------->   24.2 --------------------------------> 1.2
1.3 ----------------->   24.3 --------------------------------> 1.3
1.4 ----------------->   24.4 --------------------------------> 1.4

And in the opposite direction it looks like:

A

1.1 <------------------	25.1 <-------------------------------- 1.1
1.2 <------------------ 25.2 <-------------------------------- 1.2
1.3 <------------------ 25.3 <-------------------------------- 1.3
1.4 <------------------ 25.4 <-------------------------------- 1.4

If there aren't any other conflicting areas, all other areas can be 
routed normally.


That seems straightforward enough.


I could set up a test with you.


Thanks. However...


The commands available seem to suggest an individual mapping is required for
every host. Is it also possible to map a whole area with a single mapping?

It didn't use to be, but the manual says it should be possible on some 
release 12's but not all.


My poor old IGS has version 10.0(6) so it doesn't appear I would be able to map
whole areas. The manual seems to say that no communication is possible between
the two networks unless mapping entries exist for each of the hosts that want
to communicate. This suggests I would need a mapping entry for every host on
HECnet and every host on the other network. I think that would probably be
too difficult to maintain and might not even fit in the NVRAM.

Maybe someone with a later version of IOS might like to try?

Regards,
Peter Coghlan.