Talk across SIP networks

[size13]

Maybe I'm having a dense day, but I can't find an answer.

Can a Skype user for example talk to a VOIPBuster or tescotalk user for free?

Or is it only users of the same network that talk to each other using the sip client?

>> Edited by size13 on Tuesday 21st February 13:01

[Plotloss]

I believe Skype runs over a proprietary protocol and is therefore not compatible.

Personally I would drop Skype PDQ as its going to be used as a voice spam channel by eBay...

[GreenV8S]

As far as I can work out, all these messenger-like services only enable you to connect to people who are registered in the same directory (i.e. SIP service).

[guydw]

GreenV8S is correct.

What Skype are offerring is basically a database of users and IP addresses (this is really over simplified).

This is similar to what BT offer, it's just that their switch has names and telephone numbers.

In order to "roam" across providers they would need to peer with one another and share data. I'm sure this would happen, but I would guess that commercially it's a bit of a minefield. Technically it would be hard too as it would require sharing the entire databese - I can see many problems with this....

With PSTN it's easy, you just say that evey number that is prefixed 001 you send to your standard interconnecxt point, and someone routes it from there...