Hi, IngemarSorry for slow response (I am on vacation and having very limited email access). The restriction imposed by RFC2198 that only allow the redundant data be shifted backward seems quite arbitrary. The intention of this draft is just to relax that restriction so that the redundant data can be shifted forward. There are cases where forward shifting of the redundant data can be advantageous (as illustrated by the anti-shadow example in Appendix A in the draft). In other words, improving the delay is not the gaol of this draft. regards, -Qiaobing Ingemar Johansson S wrote: Hi Read the draft and although I understand the concept I fail to realize what is gained with forward shifted redundancy. Could you please elaborate what the possible gain with forward shifted redundancy is, compared to what is specified in RFC2198. As I see it both alternatives will eventually give the same delay. Regards Ingemar-----Original Message----- From: avt-request at ietf.org [mailto:avt-request at ietf.org] Sent: den 22 september 2007 18:00 To: avt at ietf.org Subject: avt Digest, Vol 41, Issue 22 Send avt mailing list submissions to avt at ietf.org To subscribe or unsubscribe via the World Wide Web, visit https://www1.ietf.org/mailman/listinfo/avt or, via email, send a message with subject or body 'help' to avt-request at ietf.org You can reach the person managing the list at avt-owner at ietf.org When replying, please edit your Subject line so it is more specific than "Re: Contents of avt digest..." Today's Topics: 1. I-D ACTION:draft-ietf-avt-forward-shifted-red-00.txt (Internet-Drafts at ietf.org) ---------------------------------------------------------------------- Message: 1 Date: Fri, 21 Sep 2007 12:15:01 -0400 From: Internet-Drafts at ietf.org Subject: [AVT] I-D ACTION:draft-ietf-avt-forward-shifted-red-00.txt To: i-d-announce at ietf.org Cc: avt at ietf.org Message-ID: <E1IYl9h-0004GN-Rw at stiedprstage1.ietf.org> Content-Type: text/plain; charset="us-ascii" A New Internet-Draft is available from the on-line Internet-Drafts directories. This draft is a work item of the Audio/Video Transport Working Group of the IETF. Title : Forward-shifted RTP Redundancy Payload Support Author(s) : Q. Xie, J. Schumacher Filename : draft-ietf-avt-forward-shifted-red-00.txt Pages : 13 Date : 2007-9-21 This document defines a simple enhancement to RFC 2198 to support RTP sessions with forward-shifted redundant encodings, i.e., redundant data is sent before the corresponding primary data. Forward-shifted redundancy can be used to conceal losses of a large number of consecutive media frames (e.g., consecutive loss of seconds or even tens of seconds of media). A URL for this Internet-Draft is: http://www.ietf.org/internet-drafts/draft-ietf-avt-forward-shi fted-red-00.txt To remove yourself from the I-D Announcement list, send a message to i-d-announce-request at ietf.org with the word unsubscribe in the body of the message. You can also visit https://www1.ietf.org/mailman/listinfo/I-D-announce to change your subscription settings. Internet-Drafts are also available by anonymous FTP. Login with the username "anonymous" and a password of your e-mail address. After logging in, type "cd internet-drafts" and then "get draft-ietf-avt-forward-shifted-red-00.txt". A list of Internet-Drafts directories can be found in http://www.ietf.org/shadow.html or ftp://ftp.ietf.org/ietf/1shadow-sites.txt Internet-Drafts can also be obtained by e-mail. Send a message to: mailserv at ietf.org. In the body type: "FILE /internet-drafts/draft-ietf-avt-forward-shifted-red-00.txt". NOTE: The mail server at ietf.org can return the document in MIME-encoded form by using the "mpack" utility. To use this feature, insert the command "ENCODING mime" before the "FILE" command. To decode the response(s), you will need "munpack" or a MIME-compliant mail reader. Different MIME-compliant mail readers exhibit different behavior, especially when dealing with "multipart" MIME messages (i.e. documents which have been split up into multiple messages), so check your local documentation on how to manipulate these messages. Below is the data which will enable a MIME compliant mail reader implementation to automatically retrieve the ASCII version of the Internet-Draft. -------------- next part -------------- Skipped content of type multipart/alternative ------------------------------ _______________________________________________ Audio/Video Transport Working Group avt at ietf.org https://www1.ietf.org/mailman/listinfo/avt End of avt Digest, Vol 41, Issue 22 ***********************************_______________________________________________ Audio/Video Transport Working Group avt at ietf.org https://www1.ietf.org/mailman/listinfo/avt |
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