4A0-103 Exam - Question 32

Question

Click on the exhibit.

All links have 1Gbps unreserved bandwidth initially and Shared Explicit reservation style is used. After the LSP's primary and standby secondary paths are signaled, how much unreserved bandwidth is left on the links?

Examice · Accepted Answer

In the exhibit, the primary LSP path (400M) is R1-R2-R4-R6 and the secondary LSP path (300M) is R1-R3-R5-R4-R6. Since the Shared Explicit reservation style is used and the secondary path is in a standby state, it does not consume bandwidth unless the primary path fails. Therefore, only the bandwidth of the primary LSP path is deducted from the total available unreserved bandwidth. Initially, each link has 1Gbps (1000Mbps) of unreserved bandwidth. After signaling the primary path, the link R1-R2 and R2-R4 will have 1000Mbps - 400Mbps = 600Mbps of unreserved bandwidth left.

mynssen3 · Answer

The correct answer should be "D".  The secondary path is in standby state, so its active. The term "reserved bandwith" is different about "active traffic".
Even if have no active trafic on the secondary path, the standby was configured with a reserv of 300Mb, so will be a reserve of 300Mb for this lsp.

The answer C woul be correct if the secondary path was not standby active. Only in this case the lsp will reserve the traffic wen the path is used, cause it ill be active only when the primary goes down

Ranx01 · Answer

"C" is correct, the secondary path is configured with the "standby" option. A secondary path configured as standby don't carry any "active" traffic until the primary path fails, hence 600mbs will be left on the links. (1000mbs - 400mbs = 600mbs)

snowblack · Answer

D. R1-R2 will have 300Mbps left and R2-R4 will have 600Mbps left. is right answer

Aessedai · Answer

hi, anyone any idea here?  I would have thought it would be D as well cos the secondary link is standby so it's signalled @ same time as primary?

4A0-103 Exam - Question 32

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