On Tuesday 16 June 2009 12:48:20 Jeff Pyle wrote: > Exactly. This would be so incredibly useful. > > Imagine a customer with a SIP-based PRI and a T1¹s worth of bandwidth > behind it. This is a common scenario for my customers. We try to avoid > running all G.729 wherever possible because of the obvious and ugly audio > quality hit. At G.711 I can only let them use 17 channels on their 23 > channel PRI. That¹s fine for many customers but a fraction think they need > or actually need all 23 channels. Some can afford second T1 to allow them > access to the remaining 6 channels. How about <drum roll please> dynamic > codec selection by the proxy. > > We¹ve already worked out the math and routing logic in Opensips, provided > we have the following items in the customer¹s profile: > * Total bandwidth available to customer (pick a circuit type, or input raw > kbps) > * Minimum percentage bandwidth reserved for data > * Total number of calls required > > Given this information, Opensips can compute how many calls we can leave at > G.711 and after what point we have to start compressing them into G.729 (by > verifying G.729 in the SDP, and removing G.711). Thank you dialog module. > For example, on a 1.5 meg T1 with 15% reserved for data, the formula says I > can allow 12 channels at G.711, but have to compress the remaining 11. > With a 5% data margin I can get away with 15 uncompressed and 8 compressed. > Everything¹s just about ready except for the ability to work on the SDP to > make it happen. > > > - Jeff
Just as a comment ... if you have very bad quality with G.729, maybe your problem is on other place. Having T1 line's for data, just for putting VoIP traffic ast SIP+G.711 is a waste of bandwidth, but that just my opinion. Our customers uses ADSL lines ranging from 3Mb/320Kb to 10Mb/1Mb, and using the same line for Inet navitation + VoIP, over a 3M/320Kb line you could drive 5 G729 calls without any problem, and over a 10Mb/1Mb line, more than 12 ... so I don't undestand where you have problems with a 1.5Mb/1.5Mb line. -- Raúl Alexis Betancor Santana Dimensión Virtual _______________________________________________ Users mailing list [email protected] http://lists.opensips.org/cgi-bin/mailman/listinfo/users
