[asterisk-users] Call sip:user at domain.com?

[Gilles]

Hello

At this point, I have an Asterisk 1.4 + PC running XLite behind a NAT
set up with a VOSP trunk that I can use to make/receive calls to/from
the PSTN.

Now, I'd like to be able to call any number on the Net that is
advertised as "sip:user at domain.com", such as those:

www.voip-info.org/wiki/view/Phone+Numbers

Do I need to register a second trunk (FWD, etc.) through which those
calls will be made? Can't my VOSP perform both tasks (landline +
Internet calls)? Can I just let my Asterisk server connect to the
remote SIP server through the SRV DNS record and have it dial the
extension?

Any example appreciated, thank you.