September 14, 2009 - Midsized Clients

Computers are sometimes divided up into two groups, “fat” clients and “thin” clients. Strictly speaking, a fat client is something like your average desktop or laptop computer, which has everything it needs to run and operate right there inside of it. Meanwhile, thin clients have practically nothing on them, and rely on other computers, usually servers, to provide just about everything except the most basic local hardware and processing power. If you think back to the old days of computing, where you would see text terminals hooked up to a mainframe, and all the computing was being done on that mainframe, those are essentially early thin clients. Today thin clients are mostly graphical, but the concept is the same. The desktop and programs are handled by the server, and the local machine just acts as a display unit.

I think we’re starting to see, or at least have the potential to see, something in-between these two ideas. Compared to normal laptops, nearly all netbooks are very underpowered, and the subset of them that use solid-state drives instead of the normal hard drive even lack a lot of disk space. But I believe that if we change the way we interact with the file system slightly, we can change them into what I call “midsized clients”.

The idea for a midsized client came to me after I noticed that much of the data I use with my Eee PC doesn’t reside on the local machine, but rather on the file server I have set up here at home. Now, there are a lot of ways to access a remote file system locally these days, such as Samba and NFS, but I personally like to use SSHFS. But what if the data wasn’t the only thing that resided on the server? What if some, but not all, of the programs also resided on there as well? Specifically some of the larger software packages, like OpenOffice.

In fact, that’s how I use OpenOffice on my Eee PC.

Naturally, this also seems a lot like accessing applications through a web browser. Google Docs is a good example here since we’re already talking about office programs. But, in my opinion at least, I don’t believe that accessing a web app through an underpowered, low-space machine qualifies it as a midsized client since it doesn’t really fit into the classical examples of thin vs fat clients. To be a true midsized client, the program should not have to use any sort of special interface like a browser to be started. Instead, the user should be able to start it through normal means, such as a menu or on the command line.

Thinking like this opens up some interesting possibilities. Some locations may provide only certain programs. If I only need program X at work, I can leave it on a server at work, mount the server’s directory locally on my netbook, and then access it transparently. Data can then be stored in a folder on the same server that I use for work-related documents. If I really need to access it later, I can always VPN back into work. Meanwhile, my other small applications and my desktop remain local, so I can still use my netbook without a network connection if I need to.

It’s that last point that I think is the main difference between the traditional fat/thin client split, and this midsized client idea.

Of course, none of this is formally implemented yet, and this midsized client concept is working entirely off of very traditional, strict definitions of fat and thin clients. What’s more is that, as with many technologies today, there are some blurred lines of what actually makes something a thin, fat, or midsized client. In fact, this whole idea of a midsized client may not be new at all; I didn’t exactly Google any of this before I typed this up.

In the end, though, I find it a pretty interesting idea, and I’d be excited to see where it can go. I think I’m going to continue playing with it here at home since it seems pretty easy to get things working. I had OpenOffice working within 10 minutes of grabbing a binary package, mostly because of the simplicity of Slackware’s packages. All that was needed was some slight hacking of install script to keep from doing things locally. I also have a fast enough connection here at home that accessing it off-site through SSH is mostly painless.

Let’s see how far I can take this…