Accessing Home PC - Part 4

This is a 6-part discussions designed to help maximize resources on your home PC.We will show you how to turn on home PC remotely, establish a secure tunnel, remote control home PC, or see your home webcam.Remember, there are always alternative, I’m here to share with you my experience.

How to access resources on your home PC

Scenario: Now my computer is up but how I can access files….

So far we only talked about how to wake up your home PC.  I’m going to show you how to share the resources on your home PC.  We are going to install server software called OpenSSH for Windows on the home PC.  This software uses SSH protocol and provides you secure tunneling, proxy service, remote control, etc.  With this software installed on your home PC many things can be accomplished over this service so you can avoid open up other ports on your router for each service.

This is a 3-tier setup process that you need to run on your home PC, configure router, and setup client laptop to complete the setup.

Setting up home PC

Download the file setupssh381-20040709.zip and install the software on your home PC.  Once installed, you will need to create SSH accounts from current Windows user database.  Open a command line shell and go to C:\Program Files\OpenSSH\bin folder and type in the 2 commands:

• mkgroup –l > ..\etc\group: will create a group file in the C:\Program Files\OpenSSH\etc folder.  This file contains all the local groups in your Windows system.
• mkpasswd – l > ..\etc\passwd: will create a passwd file in the C:\Program Files\OpenSSH\etc folder.  This file contains all local user accounts and passwords information.

OpenSSH service used this information to validate login when you are accessing the SSH server.  You need to rerun these 2 commands when you want to add or remove user accounts.

Now you need to restart SSH service.  Go to Control Panel/Administrative Tools/Services, click the line “OpenSSH Server,” click stop then start buttons from the menu bar to restart the service.

Last step on PC setup is to enable the Windows firewall to allow external access to this computer.  This is accomplished by going to your Control Panel/Windows Firewall to add a new entry in the Exceptions tab. 

• Name: a meaningful name
• Port number: this is OpenSSH listening port.  Since we didn’t make a change so it is port 22 as default.

Click OK and save this entry.   Your home PC will accept any incoming SSH request through port 22 now.  You can try this from within your local home network by using the local IP.

Configure router

Now you need to enable a port forwarding rule on your router.  Login to your Actiontec MI424WR router and go to “Firewall Settings” menu and add a new rule. 

• Local Host: enter the local IP of your home PC.  Incoming SSH packets will be forwarded to this computer.
• Protocol: you should use TCP and, for security reason, select a random port instead of default SSH port 22.  I used 443 since it is not normally blocked by a corporate network.
• Forward to Port: 22 since we used the default OpenSSH service port.

Your new ‘Port Forwarding” table should look like this now:

Setting up Laptop

To connect to your home PC through SSH protocol you can download the client tool putty-0.60-installer.exe.  This client software has many utilities which allow you to connect to your home SSH service.

After completing the installation, to copy files, you can use PSCP command:

• -P 443: is the SSH port# on your router
• myaccount: is the Windows login account you sued to login to SSH server
• myhome.hopto.org: is the DNS from your DDNS provider
• c:/temp/tt.txt: is your source file on your home PC
• c:/temp: is your destination folder on your local computer

With this command you can copy files from or to your home PC.  You can type PSCP /? from the command line shell to see the available command line options.  Once you have the SSH server installed, there are plenty of user-friendly utilities out there to accomplish anything you want.  This is an extremely handy service to have.

Next, we are going to show you how to use SSH service to establish a secure tunnel and proxy out from your web browser.