13 May
2015
13 May
'15
7:30 p.m.
On May 12, 2015, at 8:05 AM, Johnny Billquist <bqt
at softjar.se> wrote:
On 2015-05-12 06:09, Cory Smelosky wrote:
Those are the rules in practice. (Well, more precisely the node address may be limited to
a smaller number, if the node is a router and uses a small packet size so the highest
address that fits in the routing message is limited to less than 255.)
The specs are somewhat more lenient, but in practice you don?t see that. For example,
Phase III routing nodes could in theory be built with a Max Address value higher than 255.
In addition, the packet processing rule for Phase IV nodes talking to a Phase III
neighbor say that the phase III node can send packets with area numbers in them, and can
receive packets from out of area (in which case the area number is left intact during
forwarding). Again, in practice that isn?t done, and I wonder why the spec allows these
strange cases.
paul
Hey,
I can't remember the limitations between a Phase IV and a Phase III node
interacting...aside from the limited area and node numbers.
Can Phase IV be used as a bridge to access Phase III nodes?
Yes. As long as the phase III nodes are in the same area.
It is pretty obvious and straight forward. Phase III nodes can talk to III or IV nodes in
the same area only, as they do not explicitly say anything about the area. Ph IV routers
will route III packets just fine within an area. Obviously, a ph III node can only address
nodes with number < 256.