When using a public network, such as an open wireless hot-spot, the potential security risk is that your conversations can be sniffed by other malicious users. Encrypting your communication is most likely the best solution; however most Internet users will find it too tedious to setup.

In this hack, we will show you how to tunnel Google Talk instant messaging client over SSH. We will create a secure communication tunnel from our computer, over an insecure network to a trusted remote server. This hack is for both Mac OS X and Windows users.

Step 1: SSH Client Setup

The first step is to download a SSH client for your operating system. Mac OS X comes with a built-in command-line SSH client. If you prefer a graphical SSH tunnel manager, you can try out the SSH Tunnel Manager for Mac OS X. For Windows, we are going to use Plink, a free command-line SSH utility.

Once you got your favorite SSH client, run the following command:

For Mac OSX:
ssh -N -L 5555:talk.google.com:5223 username@servername -fn echo
For Windows:
plink -N -batch -v -L 5555:talk.google.com:5223 -pw password username@servername

If you don’t have SSH public-private keys enabled, you will be prompted for the password to that account.

Step 2: Setup the Google Talk Client

Now that you have a working SSH tunnel, we’re ready to setup our Google Talk client.

Windows Users: Open the Google Talk client and click on the Settings link. Navigate to the Connection tab and select “Use the following proxy”. In the Host field, enter localhost and in the Port field enter 5555. Click the OK button and connect. If everything goes well, you should be able to log in with your username and password.

Mac OS X: In iChat, from the iChat menu select Preferences and navigate to the Accounts tab. Select your account and click the Server Settings tab. In the Server field type 127.0.0.1 and in the Port field type 5555. Now, go ahead and log in.

This quick hack keeps your conversations private when using insecure public networks. You can also use it to bypass firewalls at your workplace or home.