Subject: Destination port of BFD Control packet from Egress LSR in BFD-MPLS

From: "Sriram K" <[email-masked]>
Date: Fri, 4 Jan 2008 00:39:50 +0530

Hi,

Section 7 of [BFD-MPLS] states that

   "BFD control packets sent by the egress LSR are UDP packets. The
   source IP address is a routable address of the replier; the source
   port is the well-known UDP port 3784.  The destination IP address and
   UDP port MUST be copied from the source IP address and UDP port of
   the control packet received from the ingress LSR."

Section 5 of [BFD-MPLS] states that

   "On receipt of the LSP-Ping echo request message, the egress LSR MUST
   send a BFD control packet to the ingress LSR."

What would be the UDP destination port of the first BFD Control packet  that
the
Egress LSR transmits after receiving the LSP-Ping echo request message? The
destination UDP port will be unknown until a BFD Control Packet is received
from
the Ingress LSR.

Will the packet be transmitted with the source and destination UDP port as
3784
till a BFD Control packet is received from the Ingress LSR, after which the
source
UDP port is copied in to the destination UDP port. Or Am I missing some
thing?

-- 
Thanks & Regards,
Sriram K