Hi all, Anyone has experience using * through 128 kbs (or bigger) satelite link? In particular I am interested to hear how many calls could be put through 128Kbs satelite link simultaneously? Ta SJ
Senad Jordanovic <> wrote:> Hi all, > > Anyone has experience using * through > 128 kbs (or bigger) satelite link?One word of caution: you may have latency problems. Even at the speed of light, the information has a LONG way to travel...
Similar to online gaming, I would think that the propagation delay with the satelite connection would make calls unbearable. Half-duplex at its worst. my $0.02 -sb -----Original Message----- From: asterisk-users-admin@lists.digium.com [mailto:asterisk-users-admin@lists.digium.com]On Behalf Of Senad Jordanovic Sent: Wednesday, December 17, 2003 9:49 AM To: asterisk-users@lists.digium.com Subject: [Asterisk-Users] 128 kbs satelite link Hi all, Anyone has experience using * through 128 kbs (or bigger) satelite link? In particular I am interested to hear how many calls could be put through 128Kbs satelite link simultaneously? Ta SJ _______________________________________________ Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users
Senad Jordanovic said:> Hi all, > > Anyone has experience using * through > 128 kbs (or bigger) satelite link? > > In particular I am interested to hear how many calls could be put > through 128Kbs satelite link simultaneously?i havent tried a satellite link with * yet, but i do have it running on a 128k wifi link. due to the technology used for the wireless link (turbocell) the smaller packets are grouped together into a "superpacket" - this means the lower bandwidth codecs dont work very well. i found that using a higher quality codec actually gave better results. so i use ulaw all the time now - resulting in well, one concurrent call. so this really has nothing to do with answering your question, but maybe it might help someone else. duncan
David Gomillion wrote:> Senad Jordanovic <> wrote: >> Hi all, >> >> Anyone has experience using * through >> 128 kbs (or bigger) satelite link? > > One word of caution: you may have latency problems. Even at the > speed of light, the information has a LONG way to travel... > > > _______________________________________________ > Asterisk-Users mailing list > Asterisk-Users@lists.digium.com > http://lists.digium.com/mailman/listinfo/asterisk-usersSure, valid point you are making! However, devices like Cisco 53XX (and others) do put 9 calls through 128 kbs using G723. I have not tested it my self , but the www.transcom.com people say it can be done. :) I presume if G729 where to be used instead then 6 calls would be the figure. Now the question is: Can IAX be a BIG help here due to its method of sending packets? Also is IAX/IAX2 suitable for C or KU band satelites? BTW, does anyone know another provided similar to www.transcom.com ? Ta SJ
On Wed, 2003-12-17 at 08:48, Senad Jordanovic wrote:> Hi all, > > Anyone has experience using * through > 128 kbs (or bigger) satelite link? > > In particular I am interested to hear how many calls could be put > through 128Kbs satelite link simultaneously?128k may seem like the bottleneck, but it may not be the true limiting factor for you. Ping some machine near or for sure the machine you will be calling and see what kind of delay you will be dealing with on top of the packetizing of the audio. Basically add at least 20ms to the ping time to get an idea of the base line lag you will have. To give you an idea, my 14 hop trip to the gateway I was using is between 55-77ms on ping time, add the 20 ms packet size and your get 75-97ms base line lag. If you are using a jitter buffer, that adds a little more to the time so that it can deal with drop packets. I think I heard that satalite first hops are usually in the 400ms range. Are you prepared for half second or more delays? As far as call numbers, 1 for sure any codec if the only part that is a bottleneck is your link. 2 calls with occasional drop outs with almost any codec but ulaw or alaw. 3 calls will be pushing it with just about any codec. I could occasionally handle 3 calls with GSM on my 256k cable modem before call quality was significantly impaired. -- Steven Critchfield <critch@basesys.com>
Hi! Last week i talk to a person in senegal (i?m in brazil) with a 64 Kbs sattelite link and the latency was about 10 seconds! Like you are talking to the moon. miklos ----- Original Message ----- From: "Senad Jordanovic" <senad@boltblue.com> To: <asterisk-users@lists.digium.com> Sent: Wednesday, December 17, 2003 1:52 PM Subject: RE: [Asterisk-Users] 128 kbs satelite link> David Gomillion wrote: > > Senad Jordanovic <> wrote: > >> Hi all, > >> > >> Anyone has experience using * through > >> 128 kbs (or bigger) satelite link? > > > > One word of caution: you may have latency problems. Even at the > > speed of light, the information has a LONG way to travel... > > > > > > _______________________________________________ > > Asterisk-Users mailing list > > Asterisk-Users@lists.digium.com > > http://lists.digium.com/mailman/listinfo/asterisk-users > > Sure, valid point you are making! > > However, devices like Cisco 53XX (and others) do put 9 calls through 128 > kbs using G723. > I have not tested it my self , but the www.transcom.com people say it > can be done. :) > I presume if G729 where to be used instead then 6 calls would be the > figure. > Now the question is: > Can IAX be a BIG help here due to its method of sending packets? > Also is IAX/IAX2 suitable for C or KU band satelites? > > BTW, does anyone know another provided similar to www.transcom.com ? > > > Ta > SJ > > _______________________________________________ > Asterisk-Users mailing list > Asterisk-Users@lists.digium.com > http://lists.digium.com/mailman/listinfo/asterisk-users >
> I think I heard that satalite first hops are usually in the 400ms > range. Are you prepared for half second or more delays?Well. For all practilal reasons. NO. But, apparently the "C band" is suitable for VOIP.
> I think I heard that satalite first hops are usually in the 400ms range.Granted, my only hands-on experience with satellite internet access was a couple years ago with consumer equipment (DirecPC), I found that latency was often times as much as one second. I believe my best latency to any host on the internet was 800 ms. I'm sure there are links that can perform better, however latency will always be an issue with satellite links unless of course you can move the satellite closer to the earth. Based on my experience anything that would necessitate low latency will perform poorly over a satellite link. If there have been advances in this form of access that have lowered latency to an acceptable level I would love to hear about it. -- Tony Kava Network Administrator Pottawattamie County, Iowa
Hello, I'm using satellite link (1024/256) Eutelsat. With Gnugk and Asterisk. The average roundtrip to my Gateway (DualTalk) is about 650 ms. I think that's fine for non business telephony, just for calling to friends. -- Best regards, Mike mailto:mike@yes.net.ua
Hello, I'm using satellite link (1024/256) Eutelsat. With Gnugk and Asterisk. The average roundtrip to my Gateway (DualTalk) is about 650 ms. I think that's fine for non business telephony, just for calling to friends. -- Best regards, Mike mailto:mike@yes.net.ua
Hi, I have not incoming phone number to test, but I think I can call you. If I have termination to your country I'll call you (please give me your stationary phone, not mobile). -- Best regards, Mike mailto:mike@yes.net.ua
On Wednesday 17 December 2003 09:48 am, Senad Jordanovic wrote:> Hi all, > > Anyone has experience using * through > 128 kbs (or bigger) satelite link? > > In particular I am interested to hear how many calls could be put > through 128Kbs satelite link simultaneously?There's only 500ms lag over satelite. The rest is either misconfiguration or slow connections. (We've been connected to S.W. indies with 500ms.)> Ta > SJ > > _______________________________________________ > Asterisk-Users mailing list > Asterisk-Users@lists.digium.com > http://lists.digium.com/mailman/listinfo/asterisk-users-- Steve __________________________________________________ You actually need to constantly be alert and willing to handle things, or life will find a way to get you good!