[stunnel-users] Connecting stunnels

Ludolf Holzheid lholzheid at bihl-wiedemann.de
Wed Mar 30 14:34:54 CEST 2016

On Wed, 2016-03-30 10:54:29 +0000, Juhasz Gabor wrote:
> Hi,
> I am newbie in stunnel world so sorry for my question
> if it was already answered earlier.
> I have the following task to solve somehow :
> We have 1 server with 2 stunnel connections (any kind).
> We have e.g. http communicatoin via tunnels.
> Is there any support in stunnel to connect them somehow.
> Probably we do not need bidirectional communication.
> [client1]----- stunnel 1---> [server]------stunnel2 ----->[client2]
> So [client1] --> [client2]
> If there is no support in stunnel do you have any idea how to do it?


I'm not sure I understand what you are trying to accomplish.

Let's start with nomenclature:

 o A server is a unit (hardware or software) that provides services,
   e.g. e-mail distribution.

 o A client is a unit that uses services a server provides.

A client connects to a server if it wants to use a service.  For that,
the server listens on an address (e.g. IP host address and TCP port
number) known to the client.

For instance, a mail client establishes a TCP connection to TCP port
25 on a host running an SMTP mail server if it wants to send an

A server does not establish any connections to clients.  It just
listens on a known address and waits for clients to connect.

If, in your example, 'client2' is a server according to my definition
and 'client1' is a real client, then yes, stunnel could be used to
e.g. encrypt the traffic between 'client1' and 'client2'.



Ludolf Holzheid
Bihl+Wiedemann GmbH
Floßwörthstraße 41
68199 Mannheim, Germany
Tel: +49 621 33996-0
Fax: +49 621 3392239
mailto:lholzheid at bihl-wiedemann.de
Sitz der Gesellschaft: Mannheim
Geschäftsführer: Jochen Bihl, Bernhard Wiedemann
Amtsgericht Mannheim, HRB 5796

More information about the stunnel-users mailing list