Internet Engineering Task Force (IETF) C. Holmberg Request for Comments: 7913 Ericsson Updates: 7315 June 2016 Category: Informational ISSN: 2070-1721 P-Access-Network-Info ABNF Update
AbstractThis document updates RFC 7315, by modifying the extension-access- info part of the P-Access-Network-Info header field Augmented Backus- Naur Form (ABNF), and by adding the following 'access-info' header field parameter values to the list of 'access-info' header field parameter values in the ABNF: 'operator-specific-GI' and 'utran-sai-3gpp'. The values are defined in the ABNF but are not included in the list. Status of This Memo This document is not an Internet Standards Track specification; it is published for informational purposes. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Not all documents approved by the IESG are a candidate for any level of Internet Standard; see Section 2 of RFC 7841. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc7913.
Copyright Notice Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Update to RFC 7315 . . . . . . . . . . . . . . . . . . . . . 3 3. Security Considerations . . . . . . . . . . . . . . . . . . . 3 4. Normative References . . . . . . . . . . . . . . . . . . . . 4 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 4 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 4 RFC7315] defines the Session Initiation Protocol (SIP) [RFC3261] P-Access-Network-Info header field. The header field syntax contains an 'access-info' header field parameter, with a set of pre-defined values. Most pre-defined values follow the 'generic-param' rule [RFC3261]. However, currently the Augmented Backus-Naur Form (ABNF) [RFC5234] in [RFC7315] requires new values to follow the 'gen-value' rule [RFC3261], which is more restrictive than 'generic-param'. There is no justification for the restriction, and new values have already been defined following the 'generic-param' rule. The ABNF also defines the following 'access-info' header field parameter values: 'operator-specific-GI' and 'utran-sai-3gpp'. However, the values are not included in the list of 'access-info' values. This document updates Section 5.4 of [RFC7315], by modifying the extension-access-info part of the P-Access-Network-Info header field ABNF.
As the P-Access-Network-Info header field is mainly used in networks defined by the 3rd-Generation Partnership Project (3GPP), where new values following the 'generic-param' rule have been defined [TS.3GPP.24.229], the update is not considered to cause issues with backward compatibility. Section 5.4 of RFC 7315, as described below: Old syntax: access-info = cgi-3gpp / utran-cell-id-3gpp / dsl-location / i-wlan-node-id / ci-3gpp2 / eth-location / ci-3gpp2-femto / fiber-location / np / gstn-location /local-time-zone / dvb-rcs2-node-id / extension-access-info np = "network-provided" extension-access-info = gen-value New syntax: access-info = cgi-3gpp / utran-cell-id-3gpp / dsl-location / i-wlan-node-id / ci-3gpp2 / eth-location / ci-3gpp2-femto / fiber-location / np / gstn-location /local-time-zone / dvb-rcs2-node-id / operator-specific-GI / utran-sai-3gpp / extension-access-info np = "network-provided" extension-access-info = generic-param RFC7315]. The ABNF update defined in this document does not impact the security considerations.
[RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP: Session Initiation Protocol", RFC 3261, DOI 10.17487/RFC3261, June 2002, <http://www.rfc-editor.org/info/rfc3261>. [RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", STD 68, RFC 5234, DOI 10.17487/RFC5234, January 2008, <http://www.rfc-editor.org/info/rfc5234>. [RFC7315] Jesske, R., Drage, K., and C. Holmberg, "Private Header (P-Header) Extensions to the Session Initiation Protocol (SIP) for the 3GPP", RFC 7315, DOI 10.17487/RFC7315, July 2014, <http://www.rfc-editor.org/info/rfc7315>. [TS.3GPP.24.229] 3GPP, "IP multimedia call control protocol based on Session Initiation Protocol (SIP) and Session Description Protocol (SDP); Stage 3", 3GPP TS 24.229 13.5.1, March 2016, <http://www.3gpp.org/ftp/Specs/html-info/24229.htm>.