[Serusers] Theory behind a media proxy and NATed UA

[Felipe Louback]

But what if the caller is on the public internet and it wants to talk
to someone behind a NAT?
In this case, how will a media proxy forward the call to the NATed
client if in this case the NATed will be waiting for RTP traffic?

Tha NATed UA will send the 200 OK and then the caller party will send
traffic to a media proxy and this media proxy needs to send RTP to the
NATed UA....

I know this may be getting boring, but I am trying to understand how
it works.....

Felipe

On 10/6/05, Nils Ohlmeier <lists at ohlmeier.org> wrote:
> If one side of the connection is on the public internet and the other one
> behind NAT you do not need a RTP proxy in all cases.
> But if both parties are behind NAT then you have a classical chicken-egg
> problem. For that scenarios you defiantly need a relay in the public
> internet.
>
>   Nils
>
> On Thursday 06 October 2005 13:17, Felipe Louback wrote:
> > well, if after the NATed UA receives the 200 OK it has to start
> > sending RTP and it is symetric(sends and receive data throught the
> > same port), then there is no need of a media proxy, since the called
> > part knows from which port in the NAT box the NATed UA is using...
> > I am getting confused about why I need to use a media proxy....
> >
> > Felipe
> >
> > On 10/4/05, Felipe Louback <louback at gmail.com> wrote:
> > > > after the UA, which send the INVITE, received the 200 OK for the INIVTE
> > > > it has to start sending RTP.
> > >
> > > uhm..... I didn't know that. That is a very good explanation. If it
> > > has to start sending RTP, then the media proxy now knows what port it
> > > is using in tha NAT box. I thought that after the 200 OK, the nated UA
> > > would wait for audio to come, since it sent all the parameters in the
> > > SDP body.
> > >
> > > Thanks for the explanation.
> > >
> > > Felipe
> > >
> > > --
> > > Master Student - Electrical Engineering Department
> > > Computer Engineering and Telecommunications Research Group
> > > Universidade Federal de Minas Gerais - Brazil
> > >
> > > "For God so loved the world that he gave his one and only Son, that
> > > whoever believes in him shall not perish but have eternal life."
> > > John 3:16
> >
> > --
> > Master Student - Electrical Engineering Department
> > Computer Engineering and Telecommunications Research Group
> > Universidade Federal de Minas Gerais - Brazil
> >
> > "For God so loved the world that he gave his one and only Son, that
> > whoever believes in him shall not perish but have eternal life."
> > John 3:16
>


--
Master Student - Electrical Engineering Department
Computer Engineering and Telecommunications Research Group
Universidade Federal de Minas Gerais - Brazil

"For God so loved the world that he gave his one and only Son, that
whoever believes in him shall not perish but have eternal life."
John 3:16