Hi List, I have seen this: http://www.convergence.com.pk/iax2/trunked.html According to this table, using trunking, you can have 16 channels with 171.7 kbps bandwith using g.729 + IAX2 trunking? Sounds too good to be true... Any comments on this? Cheers, Jean-Michel. -- Ykoz Un Max - La VoIP en pr?-pay?! Essayez gratuitement - 5 cr?dits offerts. ---> http://ykoz.net/voip/max <---
Go have a look at http://www.asteriskguru.com/tool2.php and calculate it for yourself. This is without the signalling frames for call setup / teardown. (bandwidth used by those is very small). Greetz, /Z Incoming Bandwidth Outgoing Bandwidth Calls: 16 Calls: 16 RTP: 2.34 Kbps RTP: 2.34 Kbps UDP: 3.13 Kbps UDP: 3.13 Kbps IP: 4.69 Kibps IP: 4.69 Kibps Protocol: IAX2 TRUNKED Protocol: IAX2 TRUNKED Audio Codec: 8.00 Kbps Audio Codec: 8.00 Kbps *IAX2 TRUNKED is not using RTP or RTCP! *IAX2 TRUNKED is not using RTP or RTCP! Incoming bandwidth used is: *139.72 Kbps* *0.14 Mbps* *17.47 KBps* *0.02 MBps* Outgoing bandwidth used is: *139.72 Kibps* *0.14 Mbps* *17.47 KBps* *0.02 MBps* Total bidirectional bandwidth used (incoming and outgoing) is: *279.44 Kbps* *0.27 Mbps* *34.93 KBps* *0.03 MBps* Jean-Michel Hiver wrote:> Hi List, > > I have seen this: > > http://www.convergence.com.pk/iax2/trunked.html > > According to this table, using trunking, you can have 16 channels with > 171.7 kbps bandwith using g.729 + IAX2 trunking? Sounds too good to > be true... > > Any comments on this? > > Cheers, > Jean-Michel. >-------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 254 bytes Desc: OpenPGP digital signature Url : http://lists.digium.com/pipermail/asterisk-users/attachments/20050427/5b36e21d/signature.pgp
Jean-Michel Hiver wrote:> Hi List, > > I have seen this: > > http://www.convergence.com.pk/iax2/trunked.html > > According to this table, using trunking, you can have 16 channels with > 171.7 kbps bandwith using g.729 + IAX2 trunking? Sounds too good to be > true... > > Any comments on this? >If I'm reading the little blue/green chart at the top correctly, the calculations on this page use some sort of special IP that only has 12 octets of header, instead of the 20 octets the IP standard specifies. So the sum of 20 octets of IP header plus 8 octets of UDP header would be 28 octets/224 bits, instead of the 160 bits shown there. They also show an RTP header size of 8 octets; I think it should be 12. Those would have an effect, I think, on all the derived calculations. I also see a descrepancy in the bitrate they use for iLBC. Depending on the sample size, its bitrate, according to the blurb on the front page of its website, is either 13.3kbs (30ms/sample) or 15.2 (20ms/sample). The convergence site states 9kbs. So either I've got some wrong info, or they do. . . . B.