Which of the following is not a matching condition for policy routing?

Question

Options

• ASource safe zone
• BSource IP address
• CSource port number
• DDSCP priority

• A
  17% (5)
• B
  3% (1)
• C
  73% (22)
• D
  7% (2)

Explanation

Source port number is not a standard matching condition for policy routing because policy routing operates at Layer 3 (network layer) and makes forwarding decisions based on network-level attributes - port numbers are a Layer 4 (transport layer) concept typically used in firewall ACLs, not routing policy matches.

The distractors are all valid matching conditions: Source safe zone (A) identifies the logical security zone a packet originates from, which is a core criterion in zone-based policy routing (common in Huawei and similar platforms); Source IP address (B) is the most fundamental policy routing match condition, allowing traffic from specific hosts or subnets to be routed differently; DSCP priority (D) is a QoS marking in the IP header that policy routing can use to steer traffic onto specific paths based on service class.

Memory tip: Think of policy routing as a network-layer decision tool - if the attribute lives below Layer 4 (IP addresses, zones, DSCP bits in the IP header), it's fair game. Port numbers belong to TCP/UDP and are the domain of firewall rules, not routing policies.

No community discussion yet for this question.