Prevent Duplicate Client Sources Served by a Network Address Port Translator

摘要

prevent duplicate client sources served by a network address port translator. Prevent duplicate fonts on a protocol connection that uses network addresses, protocols, and port numbers to identify font applications that are served by a napt. If an incoming packet encapsulates an encrypted packet and is routed napt to the destination host, the encapsulated packet is decrypted to obtain an original source port number and an original packet protocol from the decrypted packet. A source port mapping table (spmt) is fetched by an association between the napt source address, the original source port, and the original packet protocol associated with the napt source address and port number. if an incorrect association is found, the packet is rejected as representing an illegal duplicate source; that is, a second packet from a different host served by a napt using the same source port and protocol.