nik@Shiva.COM (Nik Langrind) (11/10/90)
Is it ever permissible for a DECnet level 1 router to send a
message to an area router outside its own area? My reading of the
Routing spec indicates "no" but I'm unsure of the meaning of the
term "nearest level 2 router," so perhaps it is permitted. The
implementation that I'm maintaining (which is an Ethernet level 1
router) will forward to an area router outside its area. The area
router (a VAX) accepts and routes the message. A VAX Level 1 router
on the other hand, would have forwarded only to an area router in its
own area.
So, I would correct this seeming error, but I'm worried that it
may actually be a feature, or it may actually be the correct
behaviour.
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.........................o karsten@tfl.dk (11/10/90)
In article <1990Nov9.190156.14366@Shiva.COM>, nik@Shiva.COM (Nik Langrind) writes: > Is it ever permissible for a DECnet level 1 router to send a > message to an area router outside its own area? My reading of the > Routing spec indicates "no" but I'm unsure of the meaning of the > term "nearest level 2 router," so perhaps it is permitted. The > implementation that I'm maintaining (which is an Ethernet level 1 > router) will forward to an area router outside its area. The area > router (a VAX) accepts and routes the message. A VAX Level 1 router > on the other hand, would have forwarded only to an area router in its > own area. A level 1 router (or end node) may only talk to nodes, i.e., end nodes, and routers in its on area. If a level 1 router (or end node) wants to talk to any node, included area routers, in an other area, it must let its messages pass the nearest area router in its own area. However not all third party products follow the rules. Sunlink (from Sun) allow (or allowed) you to communicate directly from a Sun to an node in an other area and if the other node is an end node and the address of the Sun is cached then also the the other way. Karsten Nyblad TFL, A Danish Telecommunication Research Laboratory E-mail: karsten@tfl.dk