Which BGP feature should be used to avoid high memory utilization on a router? Select the
best response.

A.
soft-reconfiguration

B.
route refresh

C.
BGP communities

D.
full-mesh BGP peering

Explanation:
BGP routers have enormous routing tables so it usesmuch memory to proceed these
routes. When a BGP policy is changed, the BGP session needs to be reset for the policy to
take effect. But the resetting results in route churn and route flapping. There are two ways to
clear a BGP session without resetting the TCP session between them (this is often called
“soft reset”):
Soft-reconfiguration: stores all received (inbound) routing policy updates without
modification in a table so that when a new filter is applied, the router will use this table to
calculate the changes without resetting the TCP session between the two BGP peers . This
is a memory-intensive (high memory utilization) method and is not recommended.
Route-refresh: allows a BGP router to request a remote peer resend its BGP Adj-RIB-Out.
This allows the BGP router to reapply the inbound policy. The route-refresh capability
requires no extra memory on the local router