[OpenSIPS-Users] different between nathelper and nat_traversal

[Iñaki Baz Castillo]

2009/1/22 Pezhman Lali <lopl at lopl.net>:
> Dear,
> I find  nathelper and nat_traversal modules very similar.
> I think the only different between them is using rtpproxy.
> is any more different?

nathelper, until now, solves the NAT signalling problem. this means:
detects NAT based on request/response headers and real source IP, and
also "fixes" it by replacing privates adresses by the received public
address (in Contact for example).
nathelper communicates with RtpProxy so it can also fixes the privates
addresses in the SDP.
And also, it mantains the keepalive of natted registered users.

But nathelper has some limitations: it cannot keepalive connection
from non registered users, or SUBSCRIBE dialogs. It also require that
users behind NAT use their outbound proxy as registrar, is not,
keepalive will not work.


nat_traversal is a more ellegant and powerful solution but just for
the signalling. It doesn't control RtpProxy, but it has more features
missing in nathelper.

But please, read the *full* documentation of nat_traversal module, all
the features are well explained.

AFAIK, in a future nathelper will loose signalling related funcionts
and will become just a "driver" to manage RtpProxy and modify SDP's.


-- 
Iñaki Baz Castillo
<ibc at aliax.net>