Label Distribution Protocol
7210 SAS M, T, X, R6, Mxp MPLS Configuration Guide Page 225
Label Exchange
Label exchange is initiated by the service manager. When an SDP is attached to a service (for
example, the service gets a transport tunnel), a message is sent from the service manager to LDP.
This causes a label mapping message to be sent. Additionally, when the SDP binding is removed
from the service, the VC label is withdrawn. The peer must send a label release to confirm that the
label is not in use.
Other Reasons for Label Actions
Other reasons for label actions include:
• MTU changes: LDP withdraws the previously assigned label, and re-signals the FEC with
the new MTU in the interface parameter.
• Clear labels: When a service manager command is issued to clear the labels, the labels are
withdrawn, and new label mappings are issued.
• SDP down: When an SDP goes administratively down, the VC label associated with that
SDP for each service is withdrawn.
• Memory allocation failure: If there is no memory to store a received label, it is released.
• VC type unsupported: When an unsupported VC type is received, the received label is
released.
Cleanup
LDP closes all sockets, frees all memory, and shuts down all its tasks when it is deleted, so its
memory usage is 0 when it is not running.
To Next Page
Loading...
