SIP to SIP calls

[Andred]

Hi Guys

Hope someone can shed some light.

I am using zoiper as a SIP client.
If I register with iptel.org then calling username works fine.
if I call sip:username@iptel.org it fails. "BEARER CAPABILITY NOT AUTH"
ditto for username@sip.voipbuster.com

If I register on connection-telkom and try the above, same result.

If I call sip:username@iptel.org from voipbuster, "I get a user not found".

My understanding was that SIP to SIP calls are actually peer to peer and that the SIP proxy really only returned an IP address for the User you are trying to call.

So where is the issue.
ZOIPER
Service Provider
Nat Router

I am using Telkom ADSL with a 4 port Marconi Nat Router.

Regards

[ColinR]

Don't the providers need a peering agreement (arrangement)?

[iiith]

Try to connect after disabling the firewall on router.