Which action can be taken on a multi-access segment with OSPF speakers to reduce the performance impact during widespread convergence events?
A.
Separate the network into multiple areas for each new multiaccess segment.
B.
Enable LSA throttling in the core to slow link state advertisement updates during times of network instability.
C.
Ensure that the elected DR or BDR router can support high-volume convergence events
D.
Verify that fewer than 50 OSPF speakers are on the segment
Explanation:
http://blog.ine.com/2010/06/02/ospf-fast-convergenc/
“It is worth noting that three most important timers to tune network for sub-second convergence are the failure detection delay, initial LSA generation delay and initial
SPF delay. All other timers, such as hold and maximum time serve the purpose of stabilizing network, and affect convergence in “worst-case” unstable network
scenarios.”
More info on LSA throttling: https://www.cisco.com/c/en/us/td/docs/ios/12_0s/feature/guide/fsolsath.html
“Benefits of OSPF LSA Throttling Prior to the OSPF LSA Throttling feature, LSA generation was rate-limited for 5 seconds.That meant that changes in an LSA could not be propagated in milliseconds, so the OSPF network could not achieve millisecond convergence. The OSPF LSA
Throttling feature is enabled by default and allows faster OSPF convergence (in milliseconds). This feature can be customized.
One command controls the generation (sending) of LSAs and another command controls the receiving interval. This feature also provides a dynamic mechanism to
slow down the frequency of LSA updates in OSPF during times of network instability.”