MIME media types for ISUP and QSIG Objects (RFC3204)
Original Publication Date: 2001-Dec-01
Included in the Prior Art Database: 2019-Feb-13
Internet Society Requests For Comment (RFCs)
E. Zimmerer: AUTHOR [+6]
This document describes MIME types for application/ISUP and application/QSIG objects for use in SIP applications, according to the rules defined in RFC 2048. These types can be used to identify ISUP and QSIG objects within a SIP message such as INVITE or INFO, as might be implemented when using SIP in an environment where part of the call involves interworking to the PSTN. [STANDARDS-TRACK]
Network Working Group E. Zimmerer Request for Comments: 3204 Rankom, Inc. Category: Standards Track J. Peterson Neustar, Inc. A. Vemuri Qwest Communications L. Ong Ciena Networks F. Audet M. Watson M. Zonoun Nortel Networks December 2001
MIME media types for ISUP and QSIG Objects
Status of this Memo
This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.
Copyright (C) The Internet Society (2001). All Rights Reserved.
This document describes MIME types for application/ISUP and application/QSIG objects for use in SIP applications, according to the rules defined in RFC 2048. These types can be used to identify ISUP and QSIG objects within a SIP message such as INVITE or INFO, as might be implemented when using SIP in an environment where part of the call involves interworking to the PSTN.
ISUP (ISDN User part) defined in the ITU-T recommendations Q.761-4 is a signaling protocol used between telephony switches. There are configurations in which ISUP-encoded signaling information needs to be transported between SIP entities as part of the payload of SIP messages, where the preservation of ISUP data is necessary for the proper operation of PSTN features.
Zimmerer, et al. Standards Track [Page 1]
RFC 3204 ISUP and QSIG MIME Objects December 2001
QSIG is the analogous signaling protocol used between private branch exchanges to support calls within private telephony networks. There is a similar need to transport QSIG-encoded signaling information between SIP entities in some environments.
This document is specific to this usage and would not apply to the transportation of ISUP or QSIG messages in other applications. These media types are intended for ISUP or QSIG application information that is used within the context of a SIP session, and not as general purpose transport of SCN signaling.
The definition of media types for ISUP and QSIG application information does not address fully how the non-SIP and SIP entities exchanging messages determine or negotiate compatibility. It is assumed that this is addressed by alternative means such as the configuration of the interworking functions.
This is intended to be an IETF approved MIME type, and to be defined through an RFC. NOTE: usage of Q.SIG within SIP is neither endorsed nor recommended as a result of this MIME registration.
3. Proposed new media types
ISUP and QSIG messages are composed of arbitrary binary data that is transparent to SIP processing. The best way to encode these is to use binary encoding. This is in conformance with the restrictions imposed on the use of binary data for MIME (RFC 2045 ). It should be noted that the rules mentioned in the RFC 2045 apply to Internet mai...