Date: Sat, 11 Oct 2003 22:07:49 -0700 To: [EMAIL PROTECTED] From: John Todd <[EMAIL PROTECTED]> Subject: RE: [Asterisk-Users] SIP / IAX over satellite
[post re-ordered chronologically]
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tilghman Lesher Sent: Saturday, October 11, 2003 4:03 PM To: [EMAIL PROTECTED] Subject: Re: [Asterisk-Users] SIP / IAX over satellite
On Saturday, Oct 11, 2003, at 17:04 America/Chicago, Paul Mahler wrote:
Which satellite system?> http://www.mentat.com/skyx/skyx-gateway.html
I think you need some specialized support, even special hardware. Check
out
http://www.groundcontrol.com/igvoip_001.htm
You may need to replace TCP/IP
I don't know why he'd need to replace TCP/IP when both SIP as well as IAX use UDP/IP. There may be substantial latency, however.
-Tilghman
Well, it's that stack that needs to go. Check out the link.
Paul
Paul Mahler [EMAIL PROTECTED] phone: 650-207-9855 fax: 877-408-0105
It's unlikely that the TCP/IP stack "needs to go". IP applications work quite well over satellite, no matter what people tell you. They just get really, really slow if they're TCP due to ACK response delay, and UDP has the aforementioned 500ms lag as well.
The skyx stuff is just a forward-ACKing spoofer for TCP, and probably some smart squid derivatives to boost HTTP transfer speeds. Not useful for VoIP, but probably useful if you're doing anything that's not UDP based.
For VoIP with IAX, there may be application layer issues that are smudging your results. I would suggest that you try to get SIP working over satellite, as I have had that working with no difficulty in the past (excepting the delay issues, of course.) If you can get "raw" RTP working with SIP, but not IAX2, then perhaps the issue needs to be patched in the IAX source code if there is some timer that is expiring inside the IAX protocol. Let us know how your results with SIP work.
Again: VoIP works JUST FINE over satellite, at least as far as the voice quality goes, as long as you have decent bandwidth available. Latency is another issue, but there's nothing you're going to be able to do when you're pushing a radio wave 33,000 miles out and 33,000 miles back - physics doesn't allow for better QoS. :-)
JT
Of course, I meant 22,237 and not 33,000 miles. Bad typing day.
JT _______________________________________________ Asterisk-Users mailing list [EMAIL PROTECTED] http://lists.digium.com/mailman/listinfo/asterisk-users
