How Desktop Sharing Works

By: Dave Roos

Remote Login

Remote log-in capability allows users to access files
© Photographer: Franz Pflueg | Agency: Dreamstime

Let's say you're preparing a huge PowerPoint presentation for a big meeting on Friday. All of the PowerPoint files and PDFs and images that you want to use in your presentation are saved on the hard drive of your work computer. Thursday rolls around and you wake up with a nasty stomach virus. You don't feel well enough to go to the office, but you need to finish that presentation. Here's where remote login can help.

Until recently, virtual private networks (VPN) were the only way to remotely access work files from home. But VPN access isn't the same as accessing the hard drive of your work computer. VPN gives you access to the local area network (LAN) at your office. With VPN, you're only able to access your PowerPoint presentation files if you've saved them on the network, not just on your computer's hard drive.


Remote login, however, uses simple desktop sharing software to give you a "remote control" for accessing your computer -- and all of its software and hard drive files -- from any Internet-connected device anywhere in the world.

Remote login works exactly the same way as desktop sharing. In desktop sharing, there are two separate parties: the host computer and the remote user. To share a desktop, the host computer allows a remote user to view the contents of the host computer's desktop over the Internet. The host computer can also hand over keyboard and mouse controls to the remote user. With remote log-in, your home or work computer is the host and you (in this case) are the remote user.

Remote login requires three basic components:

  1. Software download
  2. Internet connection
  3. Secure desktop sharing network

[source: GoToMyPC]

For remote login to work, both the host computer and all remote users have to download and install the same desktop sharing software. Desktop sharing software typically includes two distinct programs:

  1. The desktop sharing client that runs on the host computer
  2. A viewer program that allows the remote user to view the contents of the host computer's desktop in a resizable window

[source: GoToMyPC]

Remote login will only work if the host computer is powered on, connected to the Internet and running the desktop sharing software. Each time you open and run the desktop sharing software on the host computer, the software starts a new session. Each session has a particular ID and/or password that's required to remotely log in to the host computer. Once the session has been established, most desktop sharing software quietly runs in the background of the host computer until a remote login request is made.­

To log in to the host computer from home (or while traveling), you'll need to run your version of the same desktop sharing software and enter in the correct session ID or password. Or some services allow you to log in through a Web site. Once you're logged in, both computers will communicate with each other over a secure desktop sharing network. Access to this network can be free or subscription-based, depending on the service. While connected, you'll have access to keyboard controls, mouse controls, all software and all files on the host machine.

For security purposes, all packets of information that are sent over the network are typically encrypted on each end with secure shell (SSH) or 128-bit advanced encryption standard (AES) encoding. For added security, no session IDs or passwords are stored on desktop sharing servers; they're automatically generated by the host machine.

Now let's look at real-time collaboration through desktop sharing.