Consider the example in Figure 8.28. Suppose Trudy is a woman-in-the- middle, who can insert datagrams into the stream of datagrams going from R1 and R2. As part of a replay attack, Trudy sends a duplicate copy of one of the datagrams sent from R1 to R2. Will R2 decrypt the duplicate datagram and forward it into the branch-office network? If not, describe in detail how R2 detects the duplicate datagram.
Consider the following scenario:
In the above scenario, R2 will not decrypt the datagram. It will not forward the datagram to the branch office network.
Reasons:
Therefore, R2 discards the duplicate packet sent by Trudy.