Cisco Certified Network Professional 2025 – 400 Free Practice Questions to Pass the Exam

Traffic hashing in EtherChannel uses a combination of source and destination IP addresses and ports to distribute traffic effectively across the available links in the channel. This method ensures that packets belonging to the same flow are sent through the same physical link, which helps maintain the order of packets and optimizes the use of the bandwidth provided by the EtherChannel.

By taking into account both the source and destination addresses along with the transport layer ports, the hashing algorithm can create a more balanced distribution of traffic. This is critical in environments with multiple hosts communicating over the same EtherChannel, as it reduces congestion and helps in the efficient use of the aggregated bandwidth.

While MAC addresses can play a role in Layer 2 hashing algorithms, relying solely on them does not provide the level of granularity necessary for effective traffic distribution in Layer 3 and Layer 4 scenarios. Similarly, focusing only on TCP port numbers would ignore essential elements like the IP addresses, which are needed for a more robust hash calculation. Therefore, using both IP addresses and ports creates a more efficient and reliable hashing mechanism that can adapt to varying traffic patterns.