Q26Network DesignMultiple answers
In a redundant hub-and-spoke “wheel” topology, every spoke is connected to the hub, and spokes also connect to other spokes. If one spoke link fails, traffic from that site can be sent to a neighboring site, which forwards it to the hub site. However, at peak hours, an overloaded link causes traffic to be rerouted to a neighbor that then becomes overloaded. This overload produces network-traffic oscillation as the load changes at each spoke site. The design supplies more redundancy but not more resiliency because the routing protocol must evaluate many alternate paths to identify the lowest-cost path. Which two design changes help improve resiliency in this situation? (Choose two.)
Select 2 answers.
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Community votes
Discussion · 9
B, E 7
Selected Answer: BE
B and E together seem right, i.e. remove the wheel links entirely and use two links to each spoke.
D, E 5
Selected Answer: DE
A. Increasing redundant paths defeats the purpose since it makes the routing protocol process many more alternate paths to determine the lowest cost path.
B. Eliminating links between every spoke kills redundancy. Site is unreachable if there is a failure on spoke link.
C. Increasing convergence timers does not solve the issue of processing many alternate paths.
D & E: Adding more links to the remote sites gives us extra redundancy together with Increasing unequal-cost parallel paths helps both links share traffic in case one link is overloaded.
Let me know what y'all think
2
This link talks about this issue, E is correct. The other best option is to remove the wheel link between every other spoke. So B is not correct. I hope it is not a typo.
https://www.nojitter.com/network-redundancy-or-resilience
2
If you add another link from each Spoke to the Hub (answer 'E'), then you get redundancy from each Spoke and do not need the Spoke-to-Spoke physical connection (answer 'B').
1
In any case, i dont think D is correct since that is what we want to avoid, i.e. avoiding the routing protocol from processing many alternate paths.
1
The answer is D&E
D, E 1
Selected Answer: DE
DE is the answer
B, E 1
Selected Answer: BE
BE. Read more carefully. they have routing protocol issues related to a lot of links between spokes. Why are you voting for adding more such links...
B, E 1
Selected Answer: BE
I think the answers are B and E.
Eliminating links between spokes prevents too much traffic oscillation and lowers the load on routing protocols. Providing multiple links to each remote site also ensures redundancy and lets traffic be rerouted to another path in the event of link failure. This improves network resiliency and traffic stability.