Default Behavior of a Layer 2 Switch

C.

If the destination MAC address is not in the CAM table (unknown destination MAC address), the switch sends the frame out all other ports that are in the same VLAN as the received frame.

This is called flooding.

It does not flood the frame out the same port on which the frame was received.

Sure, I'd be happy to provide a detailed explanation of the default behavior of a Layer 2 switch when it receives a frame with an unknown destination MAC address.

When a Layer 2 switch receives a frame, it looks up the destination MAC address in its MAC address table to determine where to forward the frame. If the destination MAC address is found in the MAC address table, the switch forwards the frame out the appropriate port. However, if the destination MAC address is not found in the MAC address table, the switch will perform one of the following actions, depending on its default behavior:

A. The Layer 2 switch forwards the packet and adds the destination MAC address to its MAC address table. This is known as "flooding with learning". In this case, the switch will flood the frame to all ports in the VLAN except for the port on which the frame was received. This ensures that the frame reaches its intended destination, even if the switch doesn't know where that destination is. At the same time, the switch will learn the location of the destination MAC address by adding it to its MAC address table, along with the port on which it was received.

B. The Layer 2 switch sends a copy of a packet to CPU for destination MAC address learning. This is known as "flooding without learning". In this case, the switch will flood the frame to all ports in the VLAN except for the port on which the frame was received, but it will not learn the location of the destination MAC address. Instead, it will send a copy of the frame to the CPU for further analysis and learning.

C. The Layer 2 switch floods packets to all ports except the receiving port in the given VLAN. This is known as "pure flooding". In this case, the switch will flood the frame to all ports in the VLAN except for the port on which the frame was received, without learning the location of the destination MAC address. This can result in a lot of unnecessary network traffic, as the frame will be sent to all devices in the VLAN.

D. The Layer 2 switch drops the received frame. This is known as "filtering". In this case, the switch will drop the frame, as it does not know where to forward it. This can result in a lot of lost network traffic, as the frame will never reach its intended destination.

It's important to note that the default behavior of a Layer 2 switch can be modified using various configuration commands. For example, you can configure the switch to forward frames with unknown destination MAC addresses to a specific port, or to flood frames only to specific ports rather than all ports in the VLAN.