http://www.rfc-editor.org/rfc/rfc1761.txt
RFC 1761: Snoop Version 2 Packet Capture File Format, B. Callaghan, R. Gilligan1995-02-01T23:00:00-00:00This paper describes the file format used by "snoop", a packet monitoring and capture program developed by Sun. This paper is provided so that people can write compatible programs to generate and interpret snoop packet capture files. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.