DECNet Good Old Days (spun from boundaries...)

James R. Cutler james.cutler at
Sun Aug 26 23:19:41 UTC 2007

Just for the record about DECNet:

At the peak of population, I managed naming and addressing 
assignments for a DECNet network with just over 8000 nodes. Local 
routers were mostly Digital Equipment, some wide area used 
Cisco.  After a major split in the network, the remaining 3500 or so 
Phase IV nodes coexisted happily with AppleTalk, IPX, and IP hosts on 
a Cisco backbone.  My multiprotocol workstation was an Apple 
Macintosh IIci. Of course, by now the routing network is all IP based 
with several tens of thousands of routes in the default-free internal network.

         When I switch, it is from Windows to Mac OS X

At 8/26/2007 11:06 AM +0200, Peter Dambier wrote:
John Osmon wrote:
>Years ago, I worked on a academic network where we had a mix
>of IPX, DECnet, Appletalk, and IP(v4).  Not all of the routers
>actually routed each protocol -- DECnet wasn't routable, and I recall
>some routers that routed IPX, while bridging IP...
I remember old DECNET, DDCMP, IPX and NetBios days.
I used to have a couple of 19.2 kilobaud async lines, 2 arcnets and
an ethernet (thinwire technology but on RG13U cables, almost yellow wire
and UHF connectors - PL-259 like CB-radio).

DDCMP could route, IPX could and NetBios was riding on either IPX or
DDCMP so it did not matter.
In its best times the network was seeing some 1000 hosts. Everything
was running 10 MBit ethernet. there were 9 segments and no routers.

I have seen you could put some 30 NetBios PCs into a single segment
or more than 200 DECNET hosts if they were connected via switches and
thinwire transceivers.

Today without thinwire or yellow cable and with switches that can do
1 Gbit between switches and 100 Mbit to devices you should be able to
keep some 1000 hosts within a single switched network.
Peter and Karin Dambier
Cesidian Root - Radice Cesidiana
Rimbacher Strasse 16
D-69509 Moerlenbach-Bonsweiher
+49(6209)795-816 (Telekom)
+49(6252)750-308 (VoIP:
mail: peter at
mail: peter at echnaton.arl.pirates

James R. Cutler
james.cutler at
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the NANOG mailing list