Network Working Group M. Petit-Huguenin Internet-Draft Stonyfish, Inc. Updates: 5245 (if approved) February 2, 2011 Intended status: Standards Track Expires: August 6, 2011 Media level ice-options SDP attribute draft-petithuguenin-mmusic-ice-attributes-level-00 Abstract This document redefines the ice-options SDP attribute as a session- level and media-level attribute. Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. This document may not be modified, and derivative works of it may not be created, except to format it for publication as an RFC or to translate it into languages other than English. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on August 6, 2011. Copyright Notice Copyright (c) 2011 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 Petit-Huguenin Expires August 6, 2011 [Page 1] Internet-Draft Media level ICE attributes February 2011 described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. ice-options Attribute . . . . . . . . . . . . . . . . . . . . . 3 4. rtp+ecn ICE option . . . . . . . . . . . . . . . . . . . . . . 3 5. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 4 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 4 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 4 8.1. Normative References . . . . . . . . . . . . . . . . . . . 4 8.2. Informative References . . . . . . . . . . . . . . . . . . 4 Appendix A. Release notes . . . . . . . . . . . . . . . . . . . . 5 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 5 Petit-Huguenin Expires August 6, 2011 [Page 2] Internet-Draft Media level ICE attributes February 2011 1. Introduction ICE [RFC5245] defines the ice-options SDP attribute as session-level only attribute, but when ICE is used with disaggregated media (see section 3 of [I-D.loreto-splices-disaggregated-media]), there is a possibility that different media uses different ICE implementations and/or different networks, and so that differents media in the same SDP require different values for this attribute. As an example, the ice-options attribute value "rtp+ecn" (defined in [I-D.ietf-avtcore-ecn-for-rtp]) signals ECN capability. Two aggregated media using two different RTP implementations may want to use different values for this attribute. Note that there is a similar problem for the ice-lite attribute but unfortunately it does not seem possible to design a way to use the ice-lite attribute at the media level that is compatible with legacy implementations that recognize only the session-level attribute. 2. Terminology The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. 3. ice-options Attribute The ice-options attribute is a session-level and media-level attribute. All future new ICE options must also defines how media-level ICE options using this new value are aggregated to eventually generate the value of the session-level ICE option, so legacy implementations that only recognize session-level ICE options can interoperate with implementations that recognize ICE options at both levels. 4. rtp+ecn ICE option If all aggregated media contains the "rtp+ecn" ICE option defined by [I-D.ietf-avtcore-ecn-for-rtp], then an "rtp+ecn" ICE option MUST be inserted at the session-level. Petit-Huguenin Expires August 6, 2011 [Page 3] Internet-Draft Media level ICE attributes February 2011 5. Security Considerations TBD 6. IANA Considerations TBD 7. Acknowledgements This document was written with the xml2rfc tool described in [RFC2629]. 8. References 8.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC5245] Rosenberg, J., "Interactive Connectivity Establishment (ICE): A Protocol for Network Address Translator (NAT) Traversal for Offer/Answer Protocols", RFC 5245, April 2010. [I-D.ietf-avtcore-ecn-for-rtp] Westerlund, M., Johansson, I., Perkins, C., and K. Carlberg, "Explicit Congestion Notification (ECN) for RTP over UDP", draft-ietf-avtcore-ecn-for-rtp-00 (work in progress), January 2011. 8.2. Informative References [RFC2629] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629, June 1999. [I-D.loreto-splices-disaggregated-media] Camarillo, G. and S. Loreto, "Disaggregated Media in the Session Initiation Protocol (SIP)", draft-loreto-splices-disaggregated-media-00 (work in progress), September 2010. Petit-Huguenin Expires August 6, 2011 [Page 4] Internet-Draft Media level ICE attributes February 2011 Appendix A. Release notes This section must be removed before publication as an RFC. Author's Address Marc Petit-Huguenin Stonyfish, Inc. Email: petithug@acm.org Petit-Huguenin Expires August 6, 2011 [Page 5]