syslog
RFC 5424 The Syslog Protocol
RFC 6587 hisotic Transmission of Syslog Messages over TCP
RFC 6012 Datagram Transport Layer Security (DTLS) Transport Mapping for Syslog
RFC 5848 Signed Syslog Messages
RFC 5427 Textual Conventions for Syslog Management
RFC 5426 Transmission of Syslog Messages over UDP
RFC 5425 Transport Layer Security (TLS) Transport Mapping for Syslog
RFC 3195 Reliable Delivery for syslog
RFC 3164 The BSD syslog Protocol
UDP port 514
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https://datatracker.ietf.org/wg/syslog/documents/