Destination port of BFD Control packet from Egress LSR in BFD-MPLS
"Sriram K" <ksriram29@gmail.com> Thu, 03 January 2008 19:11 UTC
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Date: Fri, 04 Jan 2008 00:39:50 +0530
From: Sriram K <ksriram29@gmail.com>
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Subject: Destination port of BFD Control packet from Egress LSR in BFD-MPLS
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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