For link state routing protocols, when using filter-policy import, the filtered link state information will not be calculated as routes, and its neighbors will not receive its link state information.

Question

Options

• ATRUE
• BFALSE

• A
  25% (10)
• B
  75% (30)

Explanation

Option B (FALSE) is correct because filter-policy import in link state protocols (e.g., OSPF, IS-IS) only controls which prefixes are installed into the local routing table - it does not affect the flooding of Link State Advertisements (LSAs/LSPs) to neighbors. The link state database (LSDB) synchronization and flooding mechanism operates independently of any import filter, so neighbors still receive the full link state topology information.

Option A is wrong because the statement contains a false second clause: while the first part ("not calculated as routes") is accurate for filter-policy import, claiming neighbors are also blocked from receiving the information is incorrect - flooding is a fundamental and separate function of link state protocols that filter policies do not interrupt.

Memory tip: Think of it as two separate pipelines - flooding (topology sync, always happens) and SPF/route calculation (what enters your routing table, where import filters apply). Filter-policy import sits at the end of the pipe, not at the source.

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