A security attack consisting of a retransmission of an intercepted message for the purpose of claiming to be the original sender. Thwarted by use of timestamps, as described in Integration with Time Services .
An attack in which the attacker substitutes an older message for a current message. Can be prevented by time-stamping or numbering all messages. _____________________________________________________________________________
a scenario wherein an unauthorized user retransmits packets that had been intercepted
a type of sniffer attack where the traffic is captured
An attempt to circumvent an authentication protocol by copying authentication messages from a legitimate client and then resending them during the impostor's own authentication to the server. See also nonce.
In IPsec, an attack in which a packet is captured by an intruder. The stored packet then replaces or repeats the original at a later time. To protect against such attacks, a packet can contain a field that increments during the lifetime of the secret key that is protecting the packet.
Cryptographic attack by sending a copy of an old message. One should always number or time stamp a messages before encryption.
A replay attack is a form of network attack in which a valid data transmission is maliciously or fraudulently repeated or delayed. This is carried out either by the originator or by an adversary who intercepts the data and retransmits it, possibly as part of a masquerade attack by IP packet substitution (such as stream cipher attack).