CISCO CCNA Exam – Q48

Which two link protocols are used to carry multiple VLANs over a single link? (Choose two.)

A. VTP
B. 802.1q
C. IGP
D. ISL
E. 802.3u

Correct Answers: B, D

Explanation:
Cisco switches can use two different encapsulation types for trunks, the industry standard 802.1q or the Cisco proprietary ISL. Generally, most network engineers prefer to use 802.1q since it is standards based and will interoperate with other vendors.