[rbridge] Max Network size

[Erik Nordmark]

Alper Yegin wrote:
>>only when you don't have config info. If you move ethernets within an
>>enterprise (i.e., within a campus deployment), you don't necessarily
>>contact DHCP when you move.
> 
> 
> Even than the host needs to perform some tests to know it is still
> connected to the same IP subnet. Like the reachability test outlined in
> http://ietf.org/internet-drafts/draft-ietf-dhc-dna-ipv4-11.txt . The
> test is using ARP....

Yes, but many/most existing implementations do not perform such checks.
When I move my host from one Ethernet switch port to another, or 
associated with a different 802.11 AP, the stack silently assumes that 
this is the same IP subnet as before.
While we have a DNA WG and the above draft which tries to make this work 
better, I don't think TRILL should assume that such mechanisms are 
implemented in all the hosts.

    Erik