What is a SYN attack?
Ans. A SYN attack is one in which the TCP connection initiation stage is misused by an attacker. The attacker sends faked or spoofed connection requests called the SYN packets with a non-existing source address. On receiving such packets the stack will allocate resources for this connection and respond with a SYN Ack. Because the source address was non-existent no body would respond to this SYN Ack. This would cause the resources to be blocked for a long period of time, till the connections time out. If an attacker floods your system with a large number of packets the legitimate users would not be able to access your system.
