TCP Sequence Prediction Attack

TCP is a reliable connection-oriented layer 4 (Transport Layer) protocol. Packet transfer between hosts is accomplished by the layers below layer 4 and TCP takes responsibility to making certain the packets are delivered to higher layers in the protocol stack in the correct order. To accomplish this reordering task, TCP uses the sequence number field. To successfully mount a TCP sequence prediction attack, you must first listen to communications between two systems, one of which is your target system. Then, you issue packets from your system to the target system with the source IP address of the trusted system that is communicating with the target system.