Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) — Question 387

How does SR policy operate in Segment Routing Traffic Engineering?

Answer options

• A. An SR policy for color and endpoint is deactivated at the headend as soon as the headend learns a valid candidate path for the policy.
• B. When "invalidation drop" behavior occurs, the SR policy forwarding entry is removed and the router drops all traffic that is steered into the SR policy.
• C. When a set of SID lists is associated with the SR policy designated path, traffic steering is ECMP-based according to the qualified cost of each SID-list.
• D. An active SR policy installs a BSID-keyed entry in the forwarding table to steer the packets that match the entry to the SR policy SID-list.

Correct answer: D

Explanation

The correct answer, D, is accurate because an active SR policy does indeed install a BSID-keyed entry in the forwarding table to manage traffic. Option A is incorrect as it describes policy deactivation prematurely, while option B misrepresents the 'invalidation drop' behavior, and option C incorrectly defines how traffic steering is determined, as it does not specify the mechanism correctly.