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This is an automatically generated e-mail. To reply, visit:
<a href="https://reviewboard.asterisk.org/r/1083/">https://reviewboard.asterisk.org/r/1083/</a>
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<blockquote style="margin-left: 1em; border-left: 2px solid #d0d0d0; padding-left: 10px;">
<p style="margin-top: 0;">On January 21st, 2011, 2:42 p.m., <b>Tilghman Lesher</b> wrote:</p>
<blockquote style="margin-left: 1em; border-left: 2px solid #d0d0d0; padding-left: 10px;">
<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">This is an architectural review of the changes to the IAX2 stack, only.
The basic idea of the IAX2 protocol is a non-lossy transmit of the internals of one server to another. This is merely shoehorning the new media architecture into the 64-bit bitfield, which isn't even that old. I'd like to see the versioned value of the FORMAT2 and CAPABILITY2 fields leveraged, such that we can expect this lossless transmit of codec parameters between Asterisk servers.
One considerable problem with the loss-less transmit is that of the mini-frames, due to the problem of packing this information into a single byte value. In earlier versions, this was done in a creative way, by using the MSB to encode whether the remaining 7 bits were considered a literal bit-value or the expression of the base2-log of the codec number. This was sufficient to encode up to 128 + 7 different values, which exceeded even the demands of the 64-bit bitfield conversion. One way to deal with this would be to use some of the as-yet unused values, along with a full frame, denoting which of the negotiated codecs will be encoded as which byte value (all with the top two bits set for the codec value). This would be done per-call, on a demand basis. Most calls proceed with only a single codec anyway, and the probability that there will ever be a practical need for more than the available values is extremely low, other than for pure test cases.</pre>
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<p>On January 21st, 2011, 3:16 p.m., <b>David Vossel</b> wrote:</p>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">IAX2 does not have the capability of representing media formats with attributes. This is a protocol level limitation which is outlined in my Media Architecture Proposal as being something I have no plans to address. I see no value in expanding the number of media formats IAX2 can represent unless format attributes are associated with them.</pre>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">It's certainly *feasible* that IAX2 could be heavily modified to include all of the new information that is now internally to Asterisk. The question is whether we are willing to do it or not. We've made a huge list of things we'd like to accomplish with this project, and making those changes to IAX2 just seem far less important. Even though chan_iax2 is operating in a bit of a compatability/conversion layer mode today, does not mean that someone could not come along later and improve IAX2 to support these new features. We've pretty much already decided it's not going to be a part of the effort Digium puts forth in this effort today.</pre>
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<p>- Russell</p>
<br />
<p>On January 21st, 2011, 1:52 p.m., David Vossel wrote:</p>
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<div>Review request for Asterisk Developers.</div>
<div>By David Vossel.</div>
<p style="color: grey;"><i>Updated 2011-01-21 13:52:50</i></p>
<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Description </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">This patch is the foundation of an entire new way of looking at media in Asterisk. The code present in this review is everything required to complete phase1 of my Media Architecture proposal.
For more information about this project visit the link below.
https://wiki.asterisk.org/wiki/display/AST/Media+Architecture+Proposal</pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Testing </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;">Below are the major areas I tested during development. I will continue testing as this patch is being reviewed.
-Local Channel + IAX2 channel load testing
-SIP Calls with and without video
-IAX2 Calls
-AudioHooks and apps using audiohooks
-Masquerades
-DTMF Attended Transfers
-SIP Transfers
-Gtalk
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Diffs</b> </h1>
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<li>/configure <span style="color: grey">(UNKNOWN)</span></li>
<li>/trunk/CHANGES <span style="color: grey">(303283)</span></li>
<li>/trunk/addons/chan_mobile.c <span style="color: grey">(303283)</span></li>
<li>/trunk/addons/chan_ooh323.h <span style="color: grey">(303283)</span></li>
<li>/trunk/addons/chan_ooh323.c <span style="color: grey">(303283)</span></li>
<li>/trunk/addons/format_mp3.c <span style="color: grey">(303283)</span></li>
<li>/trunk/addons/ooh323cDriver.h <span style="color: grey">(303283)</span></li>
<li>/trunk/addons/ooh323cDriver.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_alarmreceiver.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_amd.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_chanspy.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_confbridge.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_dahdibarge.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_dial.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_dictate.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_dumpchan.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_echo.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_fax.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_festival.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_followme.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_ices.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_jack.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_meetme.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_milliwatt.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_mixmonitor.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_mp3.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_nbscat.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_originate.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_parkandannounce.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_privacy.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_queue.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_record.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_rpt.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_sms.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_speech_utils.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_talkdetect.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_test.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_voicemail.c <span style="color: grey">(303283)</span></li>
<li>/trunk/apps/app_waitforsilence.c <span style="color: grey">(303283)</span></li>
<li>/trunk/bridges/bridge_multiplexed.c <span style="color: grey">(303283)</span></li>
<li>/trunk/bridges/bridge_simple.c <span style="color: grey">(303283)</span></li>
<li>/trunk/bridges/bridge_softmix.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_agent.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_alsa.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_bridge.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_console.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_dahdi.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_gtalk.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_h323.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_iax2.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_jingle.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_local.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_mgcp.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_misdn.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_multicast_rtp.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_nbs.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_oss.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_phone.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_sip.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_skinny.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_unistim.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_usbradio.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/chan_vpb.cc <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/h323/ast_h323.cxx <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/h323/chan_h323.h <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/iax2-parser.h <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/iax2-parser.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/iax2-provision.c <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/iax2.h <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/sip/include/globals.h <span style="color: grey">(303283)</span></li>
<li>/trunk/channels/sip/include/sip.h <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/codec_a_mu.c <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/codec_adpcm.c <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/codec_alaw.c <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/codec_dahdi.c <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/codec_g722.c <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/codec_g726.c <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/codec_gsm.c <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/codec_ilbc.c <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/codec_lpc10.c <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/codec_resample.c <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/codec_speex.c <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/codec_ulaw.c <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/ex_adpcm.h <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/ex_alaw.h <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/ex_g722.h <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/ex_g726.h <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/ex_gsm.h <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/ex_lpc10.h <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/ex_speex.h <span style="color: grey">(303283)</span></li>
<li>/trunk/codecs/ex_ulaw.h <span style="color: grey">(303283)</span></li>
<li>/trunk/configs/extensions.conf.sample <span style="color: grey">(303283)</span></li>
<li>/trunk/configs/queues.conf.sample <span style="color: grey">(303283)</span></li>
<li>/trunk/configure.ac <span style="color: grey">(303283)</span></li>
<li>/trunk/contrib/scripts/install_prereq <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_g719.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_g723.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_g726.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_g729.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_gsm.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_h263.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_h264.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_ilbc.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_jpeg.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_ogg_vorbis.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_pcm.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_siren14.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_siren7.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_sln.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_sln16.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_vox.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_wav.c <span style="color: grey">(303283)</span></li>
<li>/trunk/formats/format_wav_gsm.c <span style="color: grey">(303283)</span></li>
<li>/trunk/funcs/func_channel.c <span style="color: grey">(303283)</span></li>
<li>/trunk/funcs/func_db.c <span style="color: grey">(303283)</span></li>
<li>/trunk/funcs/func_frame_trace.c <span style="color: grey">(303283)</span></li>
<li>/trunk/funcs/func_pitchshift.c <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/abstract_jb.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/astdb.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/astobj2.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/audiohook.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/bridging.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/bridging_technology.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/callerid.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/channel.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/data.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/file.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/format.h <span style="color: grey">(PRE-CREATION)</span></li>
<li>/trunk/include/asterisk/format_cap.h <span style="color: grey">(PRE-CREATION)</span></li>
<li>/trunk/include/asterisk/format_pref.h <span style="color: grey">(PRE-CREATION)</span></li>
<li>/trunk/include/asterisk/frame.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/frame_defs.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/image.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/mod_format.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/pbx.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/rtp_engine.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/slin.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/slinfactory.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/speech.h <span style="color: grey">(303283)</span></li>
<li>/trunk/include/asterisk/translate.h <span style="color: grey">(303283)</span></li>
<li>/trunk/main/abstract_jb.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/app.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/asterisk.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/astobj2.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/audiohook.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/bridging.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/callerid.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/ccss.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/channel.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/cli.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/config.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/data.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/dial.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/dsp.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/features.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/file.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/format.c <span style="color: grey">(PRE-CREATION)</span></li>
<li>/trunk/main/format_cap.c <span style="color: grey">(PRE-CREATION)</span></li>
<li>/trunk/main/format_pref.c <span style="color: grey">(PRE-CREATION)</span></li>
<li>/trunk/main/frame.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/image.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/indications.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/manager.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/pbx.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/rtp_engine.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/slinfactory.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/translate.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/udptl.c <span style="color: grey">(303283)</span></li>
<li>/trunk/main/utils.c <span style="color: grey">(303283)</span></li>
<li>/trunk/pbx/pbx_spool.c <span style="color: grey">(303283)</span></li>
<li>/trunk/res/res_adsi.c <span style="color: grey">(303283)</span></li>
<li>/trunk/res/res_agi.c <span style="color: grey">(303283)</span></li>
<li>/trunk/res/res_calendar.c <span style="color: grey">(303283)</span></li>
<li>/trunk/res/res_clioriginate.c <span style="color: grey">(303283)</span></li>
<li>/trunk/res/res_fax.c <span style="color: grey">(303283)</span></li>
<li>/trunk/res/res_fax_spandsp.c <span style="color: grey">(303283)</span></li>
<li>/trunk/res/res_musiconhold.c <span style="color: grey">(303283)</span></li>
<li>/trunk/res/res_rtp_asterisk.c <span style="color: grey">(303283)</span></li>
<li>/trunk/res/res_rtp_multicast.c <span style="color: grey">(303283)</span></li>
<li>/trunk/res/res_speech.c <span style="color: grey">(303283)</span></li>
<li>/trunk/res/res_timing_timerfd.c <span style="color: grey">(303283)</span></li>
<li>/trunk/tests/test_format_api.c <span style="color: grey">(PRE-CREATION)</span></li>
</ul>
<p><a href="https://reviewboard.asterisk.org/r/1083/diff/" style="margin-left: 3em;">View Diff</a></p>
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