Cisco Certified Network Associate (CCNA) Practice Exam

What is the single logical interface that represents an EtherChannel of multiple physical channels?

1. Logical channel

2. Port channel

3. EtherChannel interface

4. Physical channel

The correct answer is: Port channel

The correct choice refers to the concept of a port channel, which is essential in network design involving EtherChannels. A port channel is a single logical interface that aggregates multiple physical Ethernet links to increase bandwidth and provide redundancy. This configuration allows the network to treat all the aggregated physical links as one cohesive unit, improving performance and fault tolerance. In practical terms, when multiple Ethernet connections are bundled together into an EtherChannel, they are represented as a single port channel interface. This abstraction simplifies management as the network devices can configure, monitor, and apply policies to this interface rather than dealing with each physical link independently. Port channels utilize standards like Link Aggregation Control Protocol (LACP) to negotiate and manage the connections, ensuring that they operate smoothly as one interface even though they are composed of several physical interfaces. This capability is particularly important in environments that require high bandwidth and reliability, such as in data centers or enterprise networks.