EtherChannel bundles multiple links into a single logical link. Which statements are true about LACP and PAgP and load balancing?

EtherChannel bundles multiple links into a single logical link. Which statements are true about LACP and PAgP and load balancing?

• A. EtherChannel bundles multiple links into a single logical link. LACP negotiates automatically; PAgP is Cisco-proprietary; load balancing is typically based on source and destination MAC/IP or other hashed fields
• B. PAgP negotiates automatically; LACP requires manual configuration
• C. EtherChannel requires no negotiation
• D. LACP and PAgP are identical in behavior

Answer: (A)

EtherChannel relies on a negotiation protocol to form a single logical link from multiple physical links. LACP, defined as a standard (IEEE/802.1AX lineage), negotiates automatically between devices to determine which links participate in the bundle and to create the aggregated link. PAgP is Cisco’s proprietary alternative that also negotiates to form the channel, but it’s vendor-specific. For how traffic is spread across the member links, the switch uses a hashing algorithm that typically considers fields from each packet—such as source and destination MAC or IP addresses, or transport-layer ports—to decide which physical link carries a given flow. This hashing preserves per-flow order while distributing load across the bundle. So the statement that EtherChannel bundles multiple links into a single logical link, LACP negotiates automatically, PAgP is Cisco-proprietary, and load balancing uses hashed fields like source/destination addresses or ports is correct because it captures the standard, automatic negotiation behavior and the common approach to distributing traffic across the aggregated links.

EtherChannel relies on a negotiation protocol to form a single logical link from multiple physical links. LACP, defined as a standard (IEEE/802.1AX lineage), negotiates automatically between devices to determine which links participate in the bundle and to create the aggregated link. PAgP is Cisco’s proprietary alternative that also negotiates to form the channel, but it’s vendor-specific. For how traffic is spread across the member links, the switch uses a hashing algorithm that typically considers fields from each packet—such as source and destination MAC or IP addresses, or transport-layer ports—to decide which physical link carries a given flow. This hashing preserves per-flow order while distributing load across the bundle.

So the statement that EtherChannel bundles multiple links into a single logical link, LACP negotiates automatically, PAgP is Cisco-proprietary, and load balancing uses hashed fields like source/destination addresses or ports is correct because it captures the standard, automatic negotiation behavior and the common approach to distributing traffic across the aggregated links.