The Resource ReserVation Protocol (RSVP) defines an ERROR_SPEC object for communicating errors. That object has a defined format that permits the definition of 256 error codes. As RSVP has been developed and extended@ the convention has been to be conservative in defining new error codes. Further@ no provision for user-defined errors exists in RSVP. This document defines a USER_ERROR_SPEC to be used in addition to the ERROR_SPEC to carry additional user information related to errors