of most general interest would probably be the ones about basic internet protocols and packets:
- https://datatracker.ietf.org/doc/html/rfc791 Internet Protocol (IPv4)
- https://datatracker.ietf.org/doc/html/rfc8200 Internet Protocol, version 6 (IPv6)
- https://datatracker.ietf.org/doc/html/rfc4253 SSH protocol
- https://datatracker.ietf.org/doc/html/rfc2616 HTTP/1.1
- https://datatracker.ietf.org/doc/html/rfc9113 HTTP/2
- https://datatracker.ietf.org/doc/html/rfc8446 TLS 1.3