Dynamic Trunking Protocol (DTP)

D

Disabling Dynamic Trunking Protocol (DTP)

Cisco's Dynamic Trunking Protocol can facilitate the automatic creation of trunks between two switches. When two connected ports are configured in dynamic mode, and at least one of the ports is configured as desirable, the two switches will negotiate the formation of a trunk across the link. DTP isn't to be confused with

VLAN Trunking Protocol (VTP), although the VTP domain does come into play.

DTP on the wire is pretty simple, essentially only advertising the VTP domain, the status of the interface, and its DTP type. These packets are transmitted in the native (or access) VLAN every 60 seconds both natively and with ISL encapsulation (tagged as VLAN 1) when DTP is enabled.

DTP (Dynamic Trunking Protocol) is a Cisco proprietary protocol that is used to negotiate trunk links between two network devices. It runs on a Layer 2 switch port, and its primary function is to negotiate whether the link between two devices should be a trunk link or an access link.

Out of the given options, the correct statement about DTP is:

A. It uses the native VLAN.

This statement is true. DTP uses the native VLAN of the switch port to send DTP frames. The native VLAN is the VLAN that is assigned to untagged traffic on a trunk link. By default, the native VLAN is VLAN 1, but it can be changed to any other VLAN.

Option B is incorrect because DTP operates independently of VTP (VLAN Trunking Protocol). VTP is used to synchronize VLAN configuration across multiple switches, whereas DTP only negotiates whether the link between two devices should be a trunk or an access link.

Option C is incorrect because DTP does not use desirable mode by default. The default mode for DTP is auto mode, which means that the switch port will listen to DTP frames and respond if it receives a DTP frame from the other end.

Option D is incorrect because DTP does not send data on VLAN 1. DTP frames are sent on the native VLAN, which could be any VLAN, including VLAN 1.

In conclusion, the correct statement about DTP is that it uses the native VLAN.