BGP MD5 authentication is designed to prevent TCP attacks. Currently, the MD5 algorithm is cracked but can still prevent common TCP attacks.


When the MD5 algorithm is adopted, the MD5 password and TCP+BGP packets are input for calculation and then result A is saved in the TCP packet. The TCP peer resolves the result to check whether the TCP packet is a fake one. If so, it discards this TCP packet to guarantee stable TCP connection.

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