[c-nsp] question about BFD

[Srividya Rao]

Hey all,

 

I have a few questions regarding BFD on Cisco:

 

-          Does BFD notify its clients (registered protocols like
OSPF/ISIS) when a link comes up? If it does, what value does that hold
in the protocol's context? Every protocol has its own hello mechanism
wherein it not only recognizes its neighbors, but also exchanges some
protocol-specific information. Hence, does BFD's notification add any
value?

-          Is it possible to promise a turnover time of 50ms (or say
even 100ms) for links on VLANs? This is because, in the case of VLANs,
BFD will have to depend on ARP to resolve the neighbors IP address and
hence BFD's timing is dependent on ARP's timing.

-          Similar to the above question, how does Cisco implement BFD
for ISIS? For an ISIS neighbor, ARP need not be necessarily resolved.
So, does BFD request ARP to resolve the neighbor's IP?

 

 

Thanks,

-- Srao