http://www.rfc-editor.org/rfc/rfc2856.txt
RFC 2856: Textual Conventions for Additional High Capacity Data Types, A. Bierman, K. McCloghrie, R. Presuhn2000-06-01T23:00:00-00:00This memo specifies new textual conventions for additional high capacity data types, intended for SNMP implementations which already support the Counter64 data type. [STANDARDS-TRACK]