Question about computer networks...see question below in detail?

Suppose Ali and B are sending packets to each other over a computer network, Z participates in the network so that Z can capture all the packets sent

Suppose Ali and B are sending packets to each other over a computer network, Z participates in the network so that Z can capture all the packets sent by A and send whatever Z wants to B. List some of the things about how Z can affect the overall scenario.

or:Suppose Ali and B are sending packets to each other over a computer network, Z participates in the network so that Z can capture all the packets sent by A and send whatever Z wants to B. List some of the things about how Z can affect the overall scenario.

Tags:computers,