BFD mode

[chintan-shah]

Hi,

Will BFD control packets have IP header running asyncronous mode ?

REgards,

Chintan

[paolo bevilacqua]

Yes, cisco uses UDP for BFD transport. See:

http://www.cisco.com/en/US/technologies/tk648/tk365/tk480/technologies_white_paper0900aecd80244005_ps6599_Products_White_Paper.html

[Mohamed Sobair]

Hi,

BFD (Bidirectional Forwading Detection) is operates and relies on the routing protocol in its first phase of implementation. BFD payload control packets are udp packets sourced udp ports between (49152 to 65535) and destination port is (3784 udp). BFD has two modes:

a) Asynchronous.

b)Demand.

In its 1st phase of implementation ONLY Asynchronous mode will be implemented.

BFD provides rapid failure detection and fast convergence.

Because some parts of BFD operats at the Data plane, Its less CPU intensive than the Normal Routing protocol hello timers.

BFD heartbeat messages are often 1 sec until BFD establishes neighbor relation.

BFD relies on the routing protocol to determine the BFD peer Ip address. BFD will be implemented in its 1st phase for the following routing protocols:

1- OSPF

2- ISIS

3- Eigrp

4- BGP

HTH

Mohamed