Possible Trunking Modes for a Switch Port

BCD

Trunking is a method used in computer networking to allow VLAN traffic to flow between network switches. VLANs are used to logically segment a network into smaller broadcast domains, which can help with network performance and security. When switches are connected together and VLAN traffic needs to be passed between them, a trunk link is required.

Switches support different modes for trunking, which determines how they handle VLAN traffic on the trunk link. The possible trunking modes for a switch port are:

1. Trunk - In this mode, the switch port is configured to carry traffic for multiple VLANs, which are identified by VLAN tags in the Ethernet frames. This mode is typically used for inter-switch links to pass traffic between VLANs on different switches.

2. Access - In this mode, the switch port is configured to carry traffic for only one VLAN. This mode is typically used for host devices like computers and servers that do not need to send or receive traffic from multiple VLANs.

3. Dynamic auto - In this mode, the switch port is configured to operate in access mode by default, but will automatically switch to trunk mode if it detects a trunk link from the other end of the connection.

4. Dynamic desirable - In this mode, the switch port is configured to actively negotiate with the other end of the connection to determine whether to operate in trunk mode or access mode.

5. Nonegotiate - In this mode, the switch port is configured to always operate in access mode and does not allow negotiation with the other end of the connection.

In the given options, the correct answers are A. transparent, B. auto, and D. desirable. However, the option F. forwarding is not a trunking mode, but rather a forwarding state in the spanning tree protocol used for loop prevention in switched networks.

• Transparent is not a trunking mode, but rather a configuration mode for VLANs. When a switch is in transparent mode, it forwards all VLAN traffic across the link without modifying the VLAN tags. This mode is typically used in conjunction with a router or firewall that is responsible for routing between VLANs.

• Auto is a dynamic trunking mode that allows the switch port to automatically negotiate with the other end of the connection to determine whether to operate in trunk mode or access mode. If the other end of the connection is also in auto mode or desirable mode, the switch port will become a trunk port.

• Desirable is also a dynamic trunking mode that allows the switch port to actively negotiate with the other end of the connection to determine whether to operate in trunk mode or access mode. If the other end of the connection is also in desirable mode or auto mode, the switch port will become a trunk port.