813题库问题

lx2020585

QUESTION 335
Which two statements about the various implementations of STP are true? (Choose two.)
A. Common Spanning Tree maintains a separate spanning-tree instance for each VLAN configured in the
network.
B. The Spanning Tree Protocol (STP) is an evolution of the IEEE 802.1w standard.
C. Per-VLAN Spanning Tree (PVST) supports 802.1Q trunking.
D. Per-VLAN Spanning Tree Plus(PVST+) is an enhancement to 802.1Q specification and is supported
only on Cisco devices.
E. Rapid Spanning Tree Protocol (RSTP) includes features equivalent to Cisco PortFast, UplinkFast, and
BackboneFast for faster network reconvergence.
F. Multiple Spanning Tree (MST) assumes one spanning-tree instance for the entire Layer 2 network,
regardless of the multiple number of VLANs.
Answer: DE
Section: Mixed Practice Questions 5
Explanation/Reference:
PVST+对802.1D改进，只有CISCO设备支持。D选项的802.1Q有笔误，要改成802.1D。
MST使用instance ，一个instance 映射多个VLAN。

这道题的答案和解释不同，我该相信哪个？

云中之舟

那答案是什么？C和E吗？

lx2020585

云中之舟 发表于 2012-1-13 10:13

                               
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那答案是什么？C和E吗？

我是说是不是应该选F而不是选E？
E答案没表示使用instance........

云中之舟

F肯定是不对的，MTS的生成树实例也是多个。单一生成树实例的是CST和RSTP

chenchanjan

F选项是错误的:
F. Multiple Spanning Tree (MST) assumes one spanning-tree instance (for the entire Layer 2 network),regardless of the multiple number of VLANs.
应该修改为:
F. Multiple Spanning Tree (MST) assumes one spanning-tree instance (for the multiple number of VLANs).
就可以選擇了,不知各位意下如何?