- From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
- Date: Thu, 25 Jul 2013 09:40:34 +1000
- To: Kiran Kumar <g.kiranreddy4u@gmail.com>
- Cc: public-webrtc <public-webrtc@w3.org>, piranna@gmail.com, cowwoc <cowwoc@bbs.darktech.org>, Göran Eriksson AP <goran.ap.eriksson@ericsson.com>
- Message-ID: <CAHp8n2mv+dhnZ5nwg7HJKzzcReU-Hr5g6482ejym87xbBcmpsQ@mail.gmail.com>
Both are probably necessary actually. Silvia. On 25 Jul 2013 01:07, "Kiran Kumar" <g.kiranreddy4u@gmail.com> wrote: > Dear Piranna, > > If the network state is not stable, and if the bandwidth levels are > oscillating at the border. (like at around 1Mbit as stated in previous > example). There is a chance for raising more number of call backs with in > less time and may result in call-back congestion ( > http://forums.electricimp.com/discussion/176/possible-callback-congestion-causes-hang/p1 > ). > Maintaining some window timer at lower levels will reduce this problem. > > According to Congestion Manager RFC (RFC 3124), Callback-based > transmission, and other call back based implementations like TCP congestion > control algorithms are all implementing timers at the lower layers only. > > > Thanks, > Kiran. > > > On Wed, Jul 24, 2013 at 7:05 PM, piranna@gmail.com <piranna@gmail.com>wrote: > >> It's not bad to have the timers inside the API, but I would wait until >> more clear use cases apear. >> >> 2013/7/24 Kiran Kumar <g.kiranreddy4u@gmail.com>: >> > Dear Goran Eriksson/Piranna, >> > >> > Yes, It can be done by application too. >> > But maintaining such timer in the lower level, might be more >> appropriate. It >> > will reduce unnecessary call backs. >> > (Even though this is may not be the perfect example, some signaling >> > protocols like SIP are maintaining their timers in the lower layers >> instead >> > of application layer). >> > >> > Thanks, >> > Kiran. >> > >> > >> > >> > On Wed, Jul 24, 2013 at 6:47 PM, Göran Eriksson AP >> > <goran.ap.eriksson@ericsson.com> wrote: >> >> >> >> >> >> >> >> 24 jul 2013 kl. 15:04 skrev "Kiran Kumar" <g.kiranreddy4u@gmail.com>: >> >> >> >> This seems to be nice Idea to send callbacks. >> >> But I suggest to add some timer on top of it. Like If the bandwidth >> drops >> >> below a certain minimum level, then it should wait for a predefined >> window >> >> time, if the bandwidth is still less than the minimum limit, then only >> it >> >> should send a call back. >> >> Because there are many network scenarios, that affects the bandwidth >> for a >> >> minute period of time, and recover to its normal state soon. >> >> >> >> >> >> That is an option but is that not up to the application to have a >> timer, a >> >> counter or what ever is needed to decide on an action? >> >> >> >> >> >> >> >> >> >> >> >> >> >> Thanks, >> >> Kiran. >> >> >> >> >> >> >> >> On Wed, Jul 24, 2013 at 11:16 AM, cowwoc <cowwoc@bbs.darktech.org> >> wrote: >> >>> >> >>> On 24/07/2013 12:26 AM, Cullen Jennings (fluffy) wrote: >> >>>> >> >>>> On Jul 18, 2013, at 6:21 AM, Stefan Håkansson LK >> >>>> <stefan.lk.hakansson@ericsson.com> wrote: >> >>>> >> >>>>> 2. Setting BW for a MediaStreamTrack >> >>>>> ------------------------------------ >> >>>>> Why: There are situations where a suitable start bit-rate can be >> known, >> >>>>> or guessed. If this knowledge could be used the perceived end-user >> >>>>> quality could be improved (since a higher quality is available from >> >>>>> start since there is no need to start at a really low bit-rate). >> >>>>> >> >>>>> There are also situations where it could be beneficial if min and >> max >> >>>>> bit-rates to be used can be influenced. >> >>>>> >> >>>>> * The app developer may know that below a certain bit-rate the >> quality >> >>>>> is so bad that the browser could stop sending it, and likewise there >> >>>>> may >> >>>>> be knowledge about a bit-rate above which the quality does not >> improve. >> >>>>> >> >>>>> * There are situations when there is an agreement between the >> service >> >>>>> provider and the connectivity provider about min and max bit-rates. >> >>>>> >> >>>>> What: Again, this depends on how much BW info is included in the >> SDP. >> >>>>> But my understanding is that there should be some (since RTCP rates >> to >> >>>>> be used are based on this info IIUC). >> >>>> >> >>>> I agree and think we need to a couple things here. One is setting the >> >>>> limits for the bandwidth but the other is using the stats interface >> to read >> >>>> the current bandwidth being used. >> >>> >> >>> >> >>> A slightly related but higher-level proposal: replace Mandatory >> >>> constraints with Optional constraints that act as Fence conditions. >> >>> >> >>> It works like this: You specify a bunch of optional constraints >> and a >> >>> callback to be invoked when a Constraint is violated. For example, I >> would >> >>> ask for a bandwidth between 1Mbit and 2Mbit. If bandwidth drops below >> the >> >>> minimum, the callback gets invoked. I then reduce the video >> resolution, or >> >>> turn off audio, or... whatever the application wants... and set new >> min/max >> >>> bandwidth bounds. If the maximum bound is surpassed, I know I can >> afford to >> >>> increase the video resolution so I do so. And so on. >> >>> >> >>> Assuming I'm wrong (you need mandatory constraints) I still think >> >>> adding this fence behavior puts control in the right place. The >> application >> >>> is uniquely positioned to decide what happens when the connection >> >>> capabilities change. >> >>> >> >>> Gili >> >>> >> >> >> > >> >> >> >> -- >> "Si quieres viajar alrededor del mundo y ser invitado a hablar en un >> monton de sitios diferentes, simplemente escribe un sistema operativo >> Unix." >> – Linus Tordvals, creador del sistema operativo Linux >> > >
Received on Wednesday, 24 July 2013 23:41:01 UTC