关于最新300-101 6.27题库的疑问

蝶舞蛇寐

本人在遇到该题时发现有两个答案，一个是TCP MSS，一个是PMTU，请问正确答案是哪个？感谢大神解答。

蝶舞蛇寐

kaiery 发表于 2018-7-3 16:37
% m1 q5 ^, n/ s( ^我在思科的官网找到这个解释TCP MSS as described earlier takes care of fragmentation at the two endpoi ...

谢谢大神指导！

chemi0213

kaiery 发表于 2018-7-3 16:37
我在思科的官网找到这个解释TCP MSS as described earlier takes care of fragmentation at the two endpoi ...

3 K& D8 c4 w. ~/ E7 y同意，若以6/27的題庫來看 Q86有出現in the path between...就是PMTUD，Q489就是TCP MSS
至於新增題Q573,Q574因為出現"between endpoints separated by a GRE tunnel"，應該是指Tunnel的兩端，故應該都選TCP MSS，請各位指教

kaiery

我在思科的官网找到这个解释TCP MSS as described earlier takes care of fragmentation at the two endpoints of a TCP connection, but it does not handle the case where there is a smaller MTU link in the middle between these two endpoints. PMTUD was developed in order to avoid fragmentation in the path between the endpoints.

2 a6 o1 c# v5 O8 j网址：https://www.cisco.com/c/en/us/su ... 5-pmtud-ipfrag.html
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2 k9 t# }: J# A& L# U简单来说，TCP MSS是用在end device的技术，而MTU是用在两个end device中间的link的技术，所以，答题的关键字是看有没有提path，有就是指link不是指end device
3 X: V9 y& k3 x8 E8 h

scallen

答案是才

kaishuo

B 不对吧，应该是 PMTUD 后面提示( without D ) 少了个 D 吧