[HECnet] DECnet area router configuration

[Johnny Billquist]

Node list don't even get transmitted within the same area.
Node names are local to each machine, and it is perfectly valid to have
different names for the same node number on different machines (although
perhaps confusing).

All routers transmit a connectivity information packet to every other
node within the same area. All area routers also transmit an area
connectivity packet to other area routers.
But these are just with node numbers, there are no node names
transmitted in these.

So it's a two level hierarchy. End nodes knows where the closest level
one router is (must have direct connection to it). All area one routers
knows the exact layout of their own area, and knows the shortest path to
any node within the area. Level one routers also knows where the closest
level two (area) router is. Level two routers knows the exact layout of
all level two routers, and the shortest path to any other level two
router (and thus any area).

Obviously, this means that all level one routers in one area must be
connected to all other routers within that same area, by just passing
through other level one routers.

And all level two routers must be connected (directly) to all other
level two routers by just going through level two routers.

	Johnny

gerry77 at mail.com wrote:
On Thu, 3 Dec 2009 10:53:31 -0800, you wrote:
SHOW KNOWN AREAS is showing 9 areas, which is good.   SHOW KNOWN NODES isn't showing any new nodes though.   And a TELL 1.400 SHOW KNOWN NODES isn't showing my nodes yet. (I'm area 42 if you start seeing it in the node list).
I'd have to check the docs, but IIRC the node list doesn't get transmitted
to different areas. Area routers exchange among themselves infos about their
area reachability and answer yes or not to the reachability of any node
under their scope (i.e. in their area), but do not transfer the whole area
contents to other nodes.
To see new nodes in SHOW KNOWN NODES you'll have to do a COPY KNOWN NODES
from a node that already knows the nodes you are interested in, then you'll
see all the nodes on a reachable area marked as reachable (even if the
specific node is powered off).
But do not take for granted this whole theory. :-)
G.
Usual disclaimer: Excuse my English: it's not my native language.


-- 
Johnny Billquist                                   || "I'm on a bus
                                                                  ||   on a psychedelic trip
email: bqt at softjar.se                         ||   Reading murder books
pdp is alive!                                         ||   tryin' to stay hip" - B. Idol