350-001 415Q Q114 答案是否有誤?

supisces

QUESTION 114
8 l3 S, ^( l* z' Y; E; n( ]& uLoop guard and UniDirectional Link Detection both protect against Layer 2 STP loops. In which two ways does loop guard differ from UDLD in loop detection and
: f% W$ L& B7 X* Oprevention? (Choose two.)

A. Loop guard can be used with root guard simultaneously on the same port on the same VLAN while UDLD cannot.
! s2 T5 T; |% o& l3 j+ {* ], |B. UDLD protects against STP failures caused by cabling problems that create one-way links.
C. Loop guard detects and protects against duplicate packets being received and transmitted on different ports.
7 H9 x: d3 `8 B, q8 B: KD. UDLD protects against unidirectional cabling problems on copper and fiber media.
% X; {) q$ b: J+ ^. ^( ?* ?" Y" cE. Loop guard protects against STP failures caused by problems that result in the loss of BPDUs from a designated switch port.
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Answer: BE

答案 E 沒有爭議
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認為答案不是 B 的人說, 官方的書裏 Switching volume 1 page 213 提到 B 的功能同時可被兩者提供.
(誰有書可以證實一下的?)

1 ~8 Q, Z+ }4 \+ S1 l0 ^認為答案是 D 的人說,
9 }9 z# s2 o5 Q( V7 l. b* DUDLD的运行分为两种模式：normal (默认) 和aggressive。Normal模式只能检测光纤上的单向链路故障，而aggressive模式不仅能够检测光纤上的单向链路故障，还能检测双绞线上的单向链路故障。
! U$ k) ?' y6 K% }" F; O: R+ Chttp://www.cisco.com/en/US/docs/switches/lan/catalyst3560/software/release/12.2_58_se/configuration/guide/swudld.html

( Z9 I' d& G/ @不知道大家有甚麼看法?

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redfield

搭车问一下111题，答案是没有端口block，但是怎么看应该是有两个端口会block的，有没有人来解答一下

prince786

Thank you so so much 111111111111111111111111111111111111111

supisces

redfield 发表于 2012-7-15 15:56

                               
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搭车问一下111题，答案是没有端口block，但是怎么看应该是有两个端口会block的，有没有人来解答一下

Q112 嗎?
MST 有兩棵樹,
! x. F" h3 ^8 A" \2 f在某棵樹是 block 的端口, 在另一棵樹不會是 block..

5ibob

夏天的微风

虽然不懂，但是给楼主顶上去~~

user_cisco

不用软件翻译一下， 有的东西还真看不懂， 帮你顶上去。

brian0711

windmonster