200-150 · Question #91
Which statement describes the purpose of the MAC address forwarding table of a switch?
The correct answer is B. The switch consults the forwarding table to determine the output port. A switch's MAC address forwarding table maps destination MAC addresses to physical ports, allowing the switch to make forwarding decisions at Layer 2.
Question
Which statement describes the purpose of the MAC address forwarding table of a switch?
Options
- AThe switch consults the forwarding table to determine the best route to a destination.
- BThe switch consults the forwarding table to determine the output port.
- CThe switch consults the forwarding table to determine if the packet is routable.
- DThe switch consults the forwarding table to determine if access control permits the packet.
How the community answered
(37 responses)- A3% (1)
- B92% (34)
- D5% (2)
Why each option
A switch's MAC address forwarding table maps destination MAC addresses to physical ports, allowing the switch to make forwarding decisions at Layer 2.
Determining the best route to a destination is a Layer 3 function performed by a router using a routing table, not a switch using a MAC table.
A switch performs Layer 2 forwarding by looking up the destination MAC address in the CAM (Content Addressable Memory) table to identify the specific output port, avoiding unnecessary flooding to all ports when the destination is known.
Routable packet determination is a Layer 3 decision made by routers using IP routing logic, not a function of a Layer 2 MAC forwarding table.
Access control decisions are enforced by ACLs or port security features, not by the MAC forwarding table itself.
Concept tested: Switch MAC address table and Layer 2 forwarding behavior
Source: https://www.cisco.com/c/en/us/support/docs/lan-switching/ethernet/10612-59.html
Topics
Community Discussion
No community discussion yet for this question.