BFD session bringup

Hi

I am sorry to ask very basic q here . I ran into discussion on lunch table
today with one of my friend over BFD and following is what I feel is
correct .. Can someone please confirm

I have done search on literature available but wanted some comments from
you experts as well :)
====================================

Once we enable BFD on interface ; no BFD control packets are sent .

Only when we enable BFD for a particular protocol ; the BFD control packets
are sent .

Does that mean that it first waits for routing protocol to discover the
neighbors and then only attempt to bring up BFD with those neighbors ? [
i.e if in case no IGP neighbor is discovered ; BFD will not even attempt to
bring up a session ]

i.e since it is a UDP based protocol

     source IP : self
     dest IP : discovered IGP protocol neighbor
     Src port : random
      Dest port : 3784
Self discriminator : XXXX
Your discriminator : 0000

Once it sees its own discriminator in "your discriminator" field and once
timers are negotiated ; the session can be brought up

Hence it discovers the BFD neighbors and result in BFD session bringing up .

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Please correct me if I am right ?

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Received on Wed Dec 24 2014 - 22:49:49 ART