Anti-replay
Encyclopedia
Anti-replay is a sub protocol of IPsec
that is part of Internet Engineering Task Force (IETF). The main goal of anti-replay is to avoid hackers injecting or making changes in packets that travel from a source to a destination. Anti-replay protocol uses a unidirectional security association in order to establish a secure connection between two nodes in the network. Once a secure connection is established, anti-replay protocol will use a sequence number or a counter. When the source sends a message, it adds a sequence number to its packet starting at 0 and increments every time it sends another message. The other end, which is the destination, receives the message and keeps a history of the number and shifts it as the new number. If the next message has a lower number, the destination will drop the packet, and, if the number is larger than the previous one, it keeps and shifts it as the new number and so on.
IPsec
Internet Protocol Security is a protocol suite for securing Internet Protocol communications by authenticating and encrypting each IP packet of a communication session...
that is part of Internet Engineering Task Force (IETF). The main goal of anti-replay is to avoid hackers injecting or making changes in packets that travel from a source to a destination. Anti-replay protocol uses a unidirectional security association in order to establish a secure connection between two nodes in the network. Once a secure connection is established, anti-replay protocol will use a sequence number or a counter. When the source sends a message, it adds a sequence number to its packet starting at 0 and increments every time it sends another message. The other end, which is the destination, receives the message and keeps a history of the number and shifts it as the new number. If the next message has a lower number, the destination will drop the packet, and, if the number is larger than the previous one, it keeps and shifts it as the new number and so on.