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On Thu, 29 Apr 2010, tom wrote:
Eion MacDonald wrote:Skype has a lot of proprietary stuff in it and (as far as I can tell) wont allow you to connect to 'proper' VOIP or SIP.On 29/04/2010 16:29, Gordon Henderson wrote:They block all 3rd party VoIP (as do most other routers with built-in VoIP - but most of them make it easy to turn it off!)1. Not true for VoIP. I use Skype, extensively for all communications to China and Far/Middle East. If Skype is not VoIP then I don't know what definition you could use. PS Skype over both SuSE and MS Win OSs (depends on computer)
Much as I hate to admit this, Skype is Voice Over Internet Pipes, (and video too), whether that makes it "proper" or not, it open for debate though ;-)
There are Skype to SIP bridges - but they're commercial! I could go out and buy licenses today for my main peering servers and offer it as a service, but I doubt my customes would pay for it (actually, I know they won't as I asked some of them who I know also use Skype)
If you want to do the plumbing you can bridge Skype and SIP yourself - google is your friend but be prepared to wast endles hours trying to make it work (from what I've read!)
It should be fairly easy to write an Apache package to allow you to connect on port80 or 443 (HTTP/HTTPS) to allow you to avoid any blocking/shaping by your 'provider' but no-one seems to have got round to it... or one of the many portmappers/tunnellers about.
The issue I see is that both ends needs to talk the same language... So while you can re-program the outgoing port on a SIP device to use (e.g.) 80 or 443, then you need the far-end to listen on those ports too - and while I run the far-end, I don't want to start fiddling with using different ports just to solve a problem that can be more easilly solved by changing broken router the ISP provides and installing a quality one.
SIP is relatively well understood - and the best way to make it work for you in a business setting is to use business quality routers, phones and ISP. BT retail provide none of this IMO.
SIP is also quite ugly - in that it needs 2 ports to work - much like FTP. One for the commands (typically 5060) and one for the data. (the audio/video streams) What's worse is that the commands sent includes the devices own IP address - so if the device is behind NAT, then it gets the internal IP address - which the far-end picks out and uses to send the audio stream to. Somewhat sub-optimal in todays NATted Internet world, so enter a whole new level of pain sorting that out )-: Some routers think they know how SIP works and use a local variant of deep packet inspection to look inside the SIP packets and mangle them as they go through the router to "fix" them. Almost all these are broken IME )-:
Gordon -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/linux_adm/list-faq.html