Configuring Basic MPLS LDP Functions

Configuring the LSR ID

Each LSR ID uniquely identifies an LSR on the network. An LSR does not have any default LSR ID. The LSR ID must be manually configured.

Enabling Global MPLS

You can perform other MPLS configurations only after enabling global MPLS.

Enabling Global MPLS LDP

You can perform other MPLS LDP configurations only after enabling global MPLS LDP.

Configuring a Local LDP Session

LDP sessions allow LSRs to establish LSPs and swap labels.

(Optional) Configuring an LDP Transport Address

An LDP session is established over a TCP connection. To set up an LDP session, two LSRs need to confirm the LDP transport address of each other and then set up a TCP connection.

(Optional) Configuring Timers for an LDP Session

An LDP session uses the following timers: link Hello send timer, link Hello hold timer, KeepAlive send timer, KeepAlive hold timer, and Exponential backoff timer.

(Optional) Configuring PHP

Penultimate hop popping (PHP) can be configured on the egress to allocate a label to an LSR at the penultimate hop, helping relieve the burden on the egress.

(Optional) Configuring an MPLS MTU on an Interface

An MPLS MTU can be configured on an interface to determine the maximum size of MPLS packets that can be forwarded each time.

(Optional) Configuring LDP Label Policies

You can configure LDP label policies to prevent the establishment of unwanted LSPs, saving memory resources.

(Optional) Configuring a Policy for Triggering LDP LSP Establishment

A policy can be configured to allow LDP to establish LSPs based on eligible routes.

(Optional) Configuring a Policy for Triggering Transit LSP Establishment

A policy for triggering transit LSP establishment can be configured to allow LDP to use a specified route to establish a transit LSP.

(Optional) Configuring Delayed Transmission of Label Withdraw Messages

The label withdraw delay function prevents the entire LDP LSP from flapping.