[SR-Users] Need a commercial SIP Service

[James Cloos]

>>>>> "KG" == Karl Grimm <karl.grimm at bigpond.com> writes:

KG> We are an Australian organisation. We are trying to find a good
KG> quality SIP provider, commercial grade, with high connectivity
KG> success rates. We have used Skype, and it works incredibly well....

Here in the States, the phrase commercial sip provider ususally implies
a sip <=> pstn gateway.

I get the impression that you instead want SIP teleconfrences, yes?

If so, the xmpp/jingle world might have better solutions.
The server at http://jabberzac.org/talk/ is in AU.

Either way, searching for 'sip teleconference' may give better results.

One of the reasons skype has more success with NATs and firewalls is
that the clients use a single socket for signaling and media.

To get the same resiliancy for sip or jingle one'd have to modfify the
clients and the proxies to do the same.  (Peeking at each incoming
packet to classify it as sip or rtp, and dispatch it accordingly is not
hard, but it /will/ have to be written.  And the modified proxy also must
incorporate rtp proxying capability.)

The IETF Standards-track solution is to use either a l3tp or a ppp/l2tp
tunnel between each client and the shared proxy.  That would avoid
modifying the sip software, but I don't know how easy or reliable it is
in practice.

For each of those options, you'll need to run a proxy somewhere outside
of your firewall, with quality AU bandwidth.  binarylane.com.au looks
like a good provider for that.

-JimC
-- 
James Cloos <cloos at jhcloos.com>         OpenPGP: 0x997A9F17ED7DAEA6