INTERNET-DRAFT Manjunath Iyer Expires: December 18, 2006 Celstream June 18, 2006 Abstraction for AV data transfers draft-manjunath-avt-data-abstraction-00.txt Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/1id-abstracts.html The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on December 18, 2006. Copyright Notice Copyright (C) The Internet Society (2006). Abstract Meeting quality of service (QoS) in a network is challenging. DiffServe architecture, given in [RFC2474] has been proposed as a solution. However, it results in a kind of self-simlalarity in the network traffic. The method results in the reduction of bit rates and discard of cells during congestion. It requires re transmission of the same data. Alternatively, the information input can be reduced with hierarchical arrangement of data in to different levels of abstraction. With the increased load on the network, the complexity of meeting QoS and the issues of congestion are to be transferred to the receiver from the network. Manjunath Expires December18, 2006 [Page 1] Internet-Draft Abstraction for AV data transfers June 2006 1. Introduction 1.1 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]. 1.2 Overview One of the techniques to assure the agreed quality of service during the transfer of the data is to provide a feed back signal to the source about the congestion. The [RFC2581] provides a method to generate the feedback information. The signal adjusts the data transfer rate so that the network is not over-loaded. An error in the signal soon results in the loss of packets to reduce the delay. In addition, the lost packets need to be re transmitted on the underlying TCP resulting in the loss of time and wastage of resources. The real time voice or video cannot afford to lose packets or increase the delay. Any skip in the packet results in total loss of information of the corresponding data. 1.3 Abstraction of information As a solution what MAY be done here is, the information content of the signal may be uniformly degraded or lowered rather than losing some packets permanently. With the congestion notification signal at the data source, the source can start transferring the data with a variable degree of abstraction proportional to the congestion. In audio or video data transfers, though the quantisation step can be adaptively increased, it results in increased and irreparable information loss. The process is equivalent to sampling the video or audio at an abstract level. The modified technique is to arrange the data as a collection of different abstractions. Manjunath Expires December18, 2006 [Page 2] Internet-Draft Abstraction for AV data transfers June 2006 2. Impact of data abstraction on the QoS Based on the congestion feedback and the service agreement, an abstract view of the data will be selected for transmission. Though any abstract level can be used, the penalty for abstraction would be in terms of increased processing at decoder and a probable and affordable degradation in the quality. For the multimedia data, incase the real time transfer is not required, the lowest abstract levels may be selected.Each abstract level of the data is the replica of the original data but for some abstraction. It is generated with a known technique, such as averaging convolution with Gaussian pulse etc that is totally reversible. However it requires computation power. The tradeoff is now between the computation at the receiver and the network resources.The attractive part of this scheme is that the retransmissions would be totally reduced.If the abstraction methods are well organized, in the most optimistic case, it provides an opportunity for the receiver to synthesize the full data from the abstraction without being over loading the network in retransmission. Manjunath Expires December18, 2006 [Page 3] Internet-Draft Abstraction for AV data transfers June 2006 3. Security Considerations While cteating the content in abstract form, the security and content distribution information may be included. The data MAY be encrypted before getting processed in to abstract levels. 4. IANA Considerations This document has no actions for IANA. Manjunath Expires December18, 2006 [Page 4] Internet-Draft Abstraction for AV data transfers June 2006 5. References 5.1 Normative References [RFC2119] Bradner, S. "Key Words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. 5.2 Informative References [RFC2474] K. Nichols, R., S. Blake., F. Baker and D. Black, "Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers ", RFC 2474, December 1998. [RFC2581] M.Allman, V. Paxson and W. Stevens, "TCP Congestion Control", RFC 2581, April 1999. Manjunath Expires December18, 2006 [Page 5] Internet-Draft Abstraction for AV data transfers June 2006 6. Author's Address Manjunath.R Celstream. 9,Prestige bluechip Opp.Christ college Bangalore-560029 INDIA Phone: 80-41191919 E-mail: manju_r_99@yahoo.com Manjunath Expires December18, 2006 [Page 6] Internet-Draft Abstraction for AV data transfers June 2006 7. Acknowledgements The author acknowledges the creators of the RFCs referred in this draft for the valuable information and the extensions based on which this draft has been created The following individuals directly contributed for encouragement, identifying Issues, suggesting resolutions to the issues found in this document: Srinivas Rao, Rangaraj. This document benefited from all these contributions. The author acknowledges the encouragement and services rendered by his family members and colleagues during the preparation of the document. Manjunath Expires December18, 2006 [Page 7] Internet-Draft Abstraction for AV data transfers June 2006 8. Full Copyright Statement Copyright (C) The Internet Society (2006). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Manjunath Expires December18, 2006 [Page 8] Internet-Draft Abstraction for AV data transfers June 2006 9. Intellectual Property Statement The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Manjunath Expires December 18, 2006 [Page 9]