Click the exhibit button below. Based on the configuration of the network policy (below), what will be the forwarding class associated with a MPLS encapsulated customer packet that arrives on a…

Question

Exhibit

Options

• AEF
• BH1
• CL1
• DH2
• EL2

• A
  13% (5)
• B
  3% (1)
• C
  3% (1)
• D
  75% (30)
• E
  8% (3)

Explanation

H2 is correct because on a Nokia SR OS dot1Q-encapsulated network port, the network QoS policy classifies ingress traffic using the outer dot1p bits - not the MPLS EXP or inner DSCP. The exhibit's policy maps dot1p=3 directly to the H2 forwarding class, making that the winning match.

Why the distractors fail:

• (A) EF - EF would require a dot1p value that maps to EF in the policy (typically dot1p 5); dot1p=3 does not qualify.
• (B) H1 - H1 is the trap for candidates who focus on EXP=6, which would often map to H1 in default MPLS network-port behavior, but on a dot1Q network port the outer dot1p takes classification priority over the MPLS EXP.
• (C) L1 - L1 tempts candidates who apply DSCP cs1 (value 8) for classification, but DSCP is an inner-header field here; the network policy on a dot1Q port doesn't reach into the inner IP header.
• (E) L2 - L2 requires a low-priority dot1p value (e.g., 1); dot1p=3 sits in the middle range and maps higher.

Memory tip: "Dot1Q port = Dot1p rules." When a Nokia network port has dot1Q encapsulation, anchor your thinking on the outer VLAN tag's dot1p value - EXP and DSCP values inside the frame are distractors designed to pull you toward H1 or L1.

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