Could those on the list who have used or tried to use VoIP over a satellite internet connection comment on how well it works or if it even works at all in a reliable way. What is the effect of latency on the VoIP path and how much is generally tolerable? routing via satellite adds about a quarter second of latency to the path. Is that too much? Eric
Voip over satellite can be done if enough bandwidth is reserved properly for it. Use the g729 codec and ask for 24 kilobits of upstream cir and you should be fine. Also you'll want to mark your packets with the EF tos bit in sip.conf. If done right the delay isn't too bad. Yes you can tell it is there, but as long as your latency doesn't fluctuate too much you should be alright.
If people don't mind taking turns talking, it will "work". It's just going to be like talking on a CB. Reminds me of talking to my grandparents in the Europe as a child in the early 80's. Frank -----Original Message----- From: asterisk-users-bounces at lists.digium.com [mailto:asterisk-users-bounces at lists.digium.com] On Behalf Of Eric Fort Sent: Friday, May 08, 2009 10:30 PM To: Asterisk Users Mailing List - Non-Commercial Discussion Subject: [asterisk-users] VoIP over satellite internet Could those on the list who have used or tried to use VoIP over a satellite internet connection comment on how well it works or if it even works at all in a reliable way. What is the effect of latency on the VoIP path and how much is generally tolerable? routing via satellite adds about a quarter second of latency to the path. Is that too much? Eric _______________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
> Message: 10 > Date: Fri, 8 May 2009 20:30:11 -0700 > From: Eric Fort <eric.fort at gmail.com> > Subject: [asterisk-users] VoIP over satellite internet > To: Asterisk Users Mailing List - Non-Commercial Discussion > <asterisk-users at lists.digium.com> > Message-ID: > <2ad2af430905082030w389822aduc877f8b0a1afe4f4 at mail.gmail.com> > Content-Type: text/plain; charset=ISO-8859-1 > > Could those on the list who have used or tried to use VoIP over a > satellite internet connection comment on how well it works or if it > even works at all in a reliable way. What is the effect of latency on > the VoIP path and how much is generally tolerable? routing via > satellite adds about a quarter second of latency to the path. Is that > too much?It is possible-- barely-- but you have to be able to put up with two to six second lags between replies and lots of stepping on each other in conversations. The feasibility will also depend on the traffic shaping/filtering of the provider and whether they black hole VoIP ports/packets. There will be a lot of delay and echo which can be compounded by an imbalance in upstream and downstream bandwidth. If you're using dialup for upstream the bandwidth _will_ be an issue. If you're looking for point-to-point communication a client-to-client push-to-talk solution like Speak Freely [1] might be a better choice. You may also want to consider-- if you're trying to use Asterisk-- a narrowband codec such as Speex. [2] I used Speak Freely over 28.8 dialup links to have conversations between Florida and Ontario almost fifteen years ago. It's more like a two-way radio than a telephone but it works very well and is win/lin cross-platform. [1] http://speak-freely.sourceforge.net/ [2] http://speex.org/ Thanks, Josh Fuller josh.fuller at telus.com The views expressed in this e-mail are mine alone and do not necessarily reflect the views of my employer.
On Fri, 2009-05-08 at 20:30 -0700, Eric Fort wrote:> Could those on the list who have used or tried to use VoIP over a > satellite internet connection comment on how well it works or if it > even works at all in a reliable way. What is the effect of latency on > the VoIP path and how much is generally tolerable? routing via > satellite adds about a quarter second of latency to the path. Is that > too much? >Yes, done it, several times. Although that was done over a leased satelite link. Any other ip-traffic had a lower priority... Had a number of hardphones (snom's & utstar's) at one end, and asterisk via ipsec-tunnels at the other end. In between a C-band satelite and a small tracking antenna on moving vehicles (cars and ships) Latency is noticable, but acceptable. Choise of codecs determine the number of available channel, given an amount of bandwith, obviously