Maximum Metric for IS-IS Interface Advertisements

C

By default, any single link can have a maximum metric value of 63. Wide metrics allow for higher metric values, and can be enabled on a per-level basis.

In IS-IS (Intermediate System to Intermediate System) protocol, metric is used to represent the cost or distance of a path to a destination network. This metric is propagated throughout the network to compute the shortest path to reach the destination.

By default, IS-IS uses a 24-bit metric field to represent the metric. This allows a maximum metric of 16777215, which is the highest possible value that can be represented by 24 bits. However, IS-IS protocol allows administrators to configure a maximum metric for each interface to prevent the advertisement of excessively high metrics that could cause routing loops or other issues.

The maximum metric that can be advertised for any interface in IS-IS depends on the implementation and configuration. However, in most implementations, the default maximum metric is 63. This means that any path with a higher metric than 63 will be considered unreachable by the receiving routers.

Therefore, the answer to the question is C. 63, which is the default maximum metric that can be advertised for any interface in IS-IS.