Remote desktop connection and NAT

[Michael Weidmann]

Dear experts,

I have to connect to a remote machine which sits behind a firewall and is
not accessible from outside because of NAT - just imagine you have to
provide some kind of support for a customer machine which is connected to
the internet with a DSL router.
In this case the customer machine would be server and I would peek into this
machine using RDC from outside.

Is it possible that the customer (i.e. the remote desktop server) initiates
the remote desktop connection? The protocol uses only one well-known TCP
port, so this could be possible. However, I have not seen any option I could
set in the Remote desktop connection client software to accept such calls.

regards
Mike

(e-mail address removed)

 

[T G]

"Michael Weidmann" <[email protected]> wrote:

Dear experts,

I have to connect to a remote machine which sits behind a firewall and is
not accessible from outside because of NAT - just imagine you have to
provide some kind of support for a customer machine which is connected to
the internet with a DSL router.
In this case the customer machine would be server and I would peek into this
machine using RDC from outside.

Is it possible that the customer (i.e. the remote desktop server) initiates
the remote desktop connection? The protocol uses only one well-known TCP
port, so this could be possible. However, I have not seen any option I could
set in the Remote desktop connection client software to accept such calls.

regards
Mike

(e-mail address removed)

no way to temporarily or permanently leave the port forwarded to the
PC in question on the NAT router?

 

[Michael Weidmann]

no way to temporarily or permanently leave the port forwarded to the
PC in question on the NAT router?

If I understand that correctly, the router should forward an incoming
connection request from the outside world to different PCs on the local
(NAT) network based on the port id of the request.
I don't think, this would be an option for all customers. There may be
"small" customers with very simple routers (e.g. a cheap DSL router) where
this is not supported.

regards
Mike

 

[Shenan Stanley]

I have to connect to a remote machine which sits behind a firewall
and is not accessible from outside because of NAT - just imagine
you have to provide some kind of support for a customer machine
which is connected to the internet with a DSL router.
In this case the customer machine would be server and I would peek
into this machine using RDC from outside.

Is it possible that the customer (i.e. the remote desktop server)
initiates the remote desktop connection? The protocol uses only one
well-known TCP port, so this could be possible. However, I have not
seen any option I could set in the Remote desktop connection client
software to accept such calls.

T G wrote in message

no way to temporarily or permanently leave the port forwarded to the
PC in question on the NAT router?

If I understand that correctly, the router should forward an incoming
connection request from the outside world to different PCs on the
local (NAT) network based on the port id of the request.
I don't think, this would be an option for all customers. There may be
"small" customers with very simple routers (e.g. a cheap DSL router)
where this is not supported.

I cannot think of routers made these days without the ability to "forward
ports". I have seen some pretty cheap DSL/CABLE MODEM routers.. All of
them had this ability and most even had remote management capabilities. I
would verify that before dismissing it.

If there is no way to forward the request or make the machine available
(otherwise) to the actual Internet - then you truly have no way to connect
to these machines while they are behind the NAT device.