[Asterisk-Users] IAX over HTTP

[Julio Arruda]

Eric Rees wrote:
> We have been running IAX through OpenVPN with SSL for 6 months without
> any trouble to Las Veags, and we are in Oklahoma.  Most of the time, IAX
> sounds better then the land line. 


Would you have some packet captures ?

Or maybe some tcptrace 'run' over a capture file ?

I would still expect packet loss would be made much worse (side-effects 
wise) in IAX over SSL than in plain UDP/someotherdatagram encapsulation.

Thinking about it, IAX endpoints would not see any packet loss, of 
course, but the jitter would "appear" much worse from the receiver point 
of view, since a packet loss would force the TCP stack to wait for the 
retransmission before sending the "not lost" IAX packets to the 
application, forcing whatever was sent ahead, to be queued in the 
receive side for up to at least RTT (I guess, since the retransmit would 
kick in after at least RTT..humm..too old to remember all TCP fancy stuff)..



> -----Original Message-----
> From: asterisk-users-bounces at lists.digium.com
> [mailto:asterisk-users-bounces at lists.digium.com] On Behalf Of Julio
> Arruda
> Sent: Friday, July 22, 2005 12:41 PM
> To: Asterisk Users Mailing List - Non-Commercial Discussion
> Subject: Re: [Asterisk-Users] IAX over HTTP
> 
> 
> Just remember that TCP will try to retransmit your lost voice packets,
> what is not exactly of any use :-).
> 
> VPNs with IPSec and others (CIPE and some UDP 'related' vpns) would not
> create this extra (and useless) overhead.
> I've used IAX over OpenVPN (with SSL as you), and it does work, to some
> level, but I would not do it for a living :-)
> 
> Iassen Hristov wrote:
> 
>>I disagree. Isn't running it over a VPN the same thing?
>>
>>I have been running with no problems:
>>a) a soft phone over a OpenVPN VPN (over TCP)
>>b) a soft phone over a MS PPTP VPN
>>c) a hard phone over a IPSec net-to-net VPN
>>
>>For the soft phone I've used X-Ten (SIP) and idefisk (IAX) For the 
>>hard phone I've used Budgetone BT-102, Sipura SPA-841 and ATCOM AT-320
> 
> 
>>(w/ IAX2 firmware).
>>
>>I've had no problems. I suppose it is a matter of a good connection.
>>
>>
>>
>>>Message: 25
>>>Date: Fri, 22 Jul 2005 13:48:09 +0200 (CEST)
>>>From: Jerry Glomph Black <asterisk-users at glomph.com>
>>>Subject: Re: [Asterisk-Users] IAX over HTTP
>>>To: Asterisk Users Mailing List - Non-Commercial Discussion
>>>	<asterisk-users at lists.digium.com>
>>>Message-ID: <Pine.LNX.4.61.0507221344450.17655 at bittycow.prognet.com>
>>>Content-Type: text/plain; charset="iso-8859-1"
>>>
>>>Doing IAX over TCP is simply a Bad Idea.
>>>
>>>Under perfect circumstances, it will work OK, but the slightest 
>>>network disturbance will result in sound gaps/distortion and/or 
>>>monster audio delay.
>>>
>>>This is not idle UDP-boosting, I've tried it.
>>>
>>>[Have had good results with UDP-based secure tunnel transport of IAX 
>>>traffic  (CIPE and OpenVPN)]