In a certain MPLS network, the LSP information of R1 and R3 is shown in the figure. At this time, the administrator enters the command ping -a 1.1.1.1 3.3.3.3 on R1. Which of the following descriptions of this scenario is correct?

In a certain MPLS network, the LSP information of R1 and R3 is shown in the figure. At this time, the administrator enters the command ping -a 1.1.1.1 3.3.3.3 on R1. Which of the following descriptions of this scenario is correct?

A . The Echo Request message received by R2 carries label 1025, while the Echo Reply message received by R2 does not carry a label.
B . The Echo Request message received by R2 carries label 1025, and the Echo Reply message received by R2 carries label 1024
C . The Echo Request message received by R2 does not carry a label, and the Echo Reply message received by R2 does not carry a label either.
D . The Echo Request message received by R2 does not carry a label, and the Echo Reply message received by R2 carries label 1024

View Answer

Answer: B