Targeted Ldp - Alcatel-Lucent 7450 Manual

Label Distribution Protocol
As a consequence of (1), Hello packets with the same source IP address should be accepted when
received over parallel unnumbered interfaces from the same peer LSR-ID. The corresponding
Hello adjacencies would be associated with a single LDP session.
The transport address for the TCP connection, which is encoded in the Hello packet, will always
be set to the LSR-ID of the node regardless if the user enabled the interface option under
configure>router>ldp>interface-parameters>interface>ipv4>transport-address.
The user can configure the local-lsr-id option on the interface and change the value of the LSR-ID
to either the local interface or to some other interface name, loopback or not, numbered or not. If
the local interface is selected or the provided interface name corresponds to an unnumbered IP
interface, the unnumbered interface borrowed IP address will be used as the LSR-ID. In all cases,
the transport address for the LDP session will be updated to the new LSR-ID value but the link
Hello packets will continue to use the interface borrowed IP address as the source IP address.
The LSR with the highest transport address, i.e., LSR-ID in this case, will bootstrap the TCP
connection and LDP session.
Source and destination IP addresses of LDP packets are the transport addresses, i.e., LDP LSR-
IDs of systems A and B in this case.

Targeted LDP

Source and destination addresses of targeted Hello packet are the LDP LSR-IDs of systems A and
B.
The user can configure the local-lsr-id option on the targeted session and change the value of the
LSR-ID to either the local interface or to some other interface name, loopback or not, numbered or
not. If the local interface is selected or the provided interface name corresponds to an unnumbered
IP interface, the unnumbered interface borrowed IP address will be used as the LSR-ID. In all
cases, the transport address for the LDP session and the source IP address of targeted Hello
message will be updated to the new LSR-ID value.
The LSR with the highest transport address, i.e., LSR-ID in this case, will bootstrap the TCP
connection and LDP session.
Source and destination IP addresses of LDP messages are the transport addresses, i.e., LDP LSR-
IDs of systems A and B in this case.
7450 ESS MPLS Guide Page 539