The TCP-AO option has been specified for more than a decade as supplant the TCP-MD5SIG option, which ExaBGP already supports. While implementations in FOSS operating systems are scarce, at least Linux provides access supports this option.

As such, ExaBGP should provide the ability to control TCP-AO on par with BGP vendors left, right, similar to the FRR feature request at least on Linux systems when available.