You wish to advertise LDP labels for all local networks; which is the most effective policy statement to use?

To advertise LDP labels for local networks, a policy must be configured to export routes into LDP. In Nokia SR OS, directly connected subnets are learned via the 'direct' protocol. An export policy statement from protocol direct will match all these routes. This allows LDP to assign a Forwarding Equivalence Class (FEC) and advertise a corresponding label for each connected network, which is the most effective and standard method to achieve the desired outcome.

A. from prefix-list direct: This matches a prefix list named "direct", not routes from the direct protocol.
B. match local: This is not a valid top-level policy statement syntax for selecting routes based on their origin protocol.
D. match protocol direct: This is also invalid syntax; from is the correct keyword to specify the source protocol in a policy entry.
E. from protocol local: This matches the router's own /32 interface addresses, not the entire subnets of the connected networks.

Nokia 7450 ESS, 7750 SR, 7950 XRS, and VSR MPLS Guide, Release 21.10.R1, Part: LDP, Section: LDP and IGP Synchronization. The guide illustrates using policies to control LDP advertisements, where from protocol is the standard match criteria for route origins like direct, static, OSPF, or IS-IS.

Nokia 7750 SR OS Router Configuration Guide, Release 21.10.R1, Part: Routing Policies, Section: Policy Statement Configuration. This section details the syntax for routing policies, confirming that from protocol is the correct structure.