On 2012-08-10 11:42, Sampsa Laine wrote: OK, my reasoning is this: 1. The z/Arch emulator hasn't got any ethenet support, just a CTC point to point link to the host Area or not makes no difference for this. 2. I'll run MULTINET on both the Debian S/390 and the host And? Another area makes no difference for this. (I thought Multinet was a TCP/IP stack in VMS... :-) ) 3. I assume I need an area for that, or am I incorrect? Yes, you are incorrect. There is nothing that requires an area here, and it just means you need to deal with a full blown DECnet stack, instead of a simpler endnode. It might be worth understanding that there is nothing technical added by going to multiple areas. It is just a complication which allows you to have more nodes, but at the cost of more complex routing. Even within one area, you can have a large number of hops between nodes. Makes no difference to DECnet. The rules for the topological layout is simple: 1. End-nodes needs to be adjacent to atleast one level 1 router. 2. All level 1 routers in an area must be able to talk with all other level 1 routers. And only level 1 routers route messages within an area, which means you cannot have an endnode in the chain. The layout can be a star, a ring, a line, a combination, hybrid, or whatever. There are absolutely no topology that you can't have. The type of links can also be anything. Ethernet, multidrop, point-to-point, or something weird. Makes no difference. Johnny Sampsa On 10 Aug 2012, at 12:40, Johnny Billquist wrote: On 2012-08-10 09:08, Sampsa Laine wrote: 5.555 LABVAX 5.556 KUHAVX 9.390 DEB390 Done (Although the area 9 thing is silly, and will probably just make your life harder). Johnny