If you needed to transport traffic coming from multiple VLANs (connected between switches),
and your CTO was insistent on using an open standard, which protocol would you use?
A.
802.11B
B.
spanning-tree
C.
802.1Q
D.
ISL
E.
VTP
F.
Q.921
Explanation:
The act involved in the above question is trunking. The two trunking protocols in the answer
choices are: 802.1Q and ISL. ISL is Cisco proprietary and IEEE 802.1Q is based on an open
standard. When non-Cisco switches are used along with Cisco switches and trunking is
required, it is best to use the 802.1Q encapsulation.
Incorrect Answers:
A: This standard is used in wireless networking and has nothing to do with VLAN switching.
B: The Spanning Tree Protocol (STP) is used to prevent loops within a bridged network.
Each VLAN runs a separate instance of the STP and this is enabled by default.
D: This is the alternative Cisco proprietary method of trunking.
E: VLAN Trunking Protocol (VTP) is a Layer 2 messaging protocol that manages the
addition, deletion, and renaming of VLANs on a network-wide basis. It is not used to actually
transport VLAN traffic.
F: This is an ISDN signaling standard and is not related with VLAN switching.
c