TCP-AO and TCP MD5 authentication support prefixes for LDP and BGP

We have extended TCP Authentication Option (TCP-AO) and TCP MD5 to support IP subnets for BGP and LDP sessions. When you configure TCP authentication with a network address and a prefix length, your chosen TCP authentication method authenticates TCP connections to the entire range of addresses under that subnet. This means you can authenticate TCP connections without needing to know the exact IP addresses of the destination devices. When IP subnets overlap, the authentication method uses the longest prefix match (LPM) to determine the exact authentication key for a specific TCP session.