Which two of these are characteristics of the 802.1Q protocol? (Choose two.)
The 802.1Q protocol is a standard protocol used for tagging VLAN frames. It is used to identify different VLANs over the same physical network. The protocol adds a tag to the Ethernet frame, which identifies the VLAN to which the frame belongs. The two characteristics of the 802.1Q protocol are:
This is known as the "Priority Code Point" (PCP) field. It allows switches to prioritize traffic based on the importance of the data being transmitted. For example, real-time traffic such as voice or video may be assigned a higher priority than email or file transfer traffic. This helps to ensure that critical traffic is delivered with minimal delay.
802.1Q is a trunking protocol, which means that it is used to carry multiple VLANs over a single physical link. It allows for the creation of virtual network segments without the need for separate physical networks. Additionally, it is capable of carrying untagged frames, which are frames that are not part of any VLAN. Untagged frames are treated as part of the native VLAN, which is typically VLAN 1.
The other answer options are incorrect:
A. It is used exclusively for tagging VLAN frames and does not address network reconvergence following switched network topology changes. This statement is incorrect as 802.1Q is not used to address network reconvergence.
B. It modifies the 802.3 frame header, and thus requires that the FCS be recomputed. This statement is incorrect as 802.1Q does not modify the 802.3 frame header.
C. It is a Layer 2 messaging protocol which maintains VLAN configurations across networks. This statement is incorrect as 802.1Q is not a messaging protocol. It is a tagging protocol.
D. It includes an 8-bit field which specifies the priority of a frame. This statement is correct and was explained above.
E. It is a trunking protocol capable of carrying untagged frames. This statement is correct and was explained above.