What protocols are used to configure trunking on a switch?

In the context of configuring trunking on a switch, the focus is on the protocols that facilitate the transmission of multiple VLANs over a single physical link. While the option stating "VLAN" might seem relevant as it represents the logical segmentation of a network into various segments, it does not specify a protocol.

Trunking specifically allows for multiple VLANs to be carried over a single connection, which is key in network design where space and efficiency are paramount. The correct choices that actually reflect specific protocols used for this configuration include VLAN Trunking Protocol (VTP), IEEE 802.1Q, and Inter-Switch Link (ISL). Among these, 802.1Q is the most widely recognized and standardized method for tagging Ethernet frames with VLAN information, thereby supporting trunking.

Thus, although "VLAN" is a fundamental concept behind why trunking is needed, it does not meet the criteria of being a protocol used for configuring trunking on a switch. Therefore, the term "VLAN" in this context lacks the specificity required to define the technical methods employed for trunk configuration.