Lightweight architecture

Hi, name is Peter Yared, CEO of ActiveGrid. Today I'm going I'm going to talk to you about lightweight architecture. Lightweight architecture is a new way to run computing applications across large clusters of commodity machines. Today the Fortune 500 runs three tier architecture, so let's look at what three tier architecture is and how it can scale into a lightweight architecture.

So the way three tier architecture works is you have a tier of web browsers, and these are machines just like your machines at home and they communicate to an enterprise. Now, the enterprises runs a cluster of web servers and these web servers are one to two-way commodity machines from places like Dell that generally cost less than $2,000. These web servers then communicate to a tier of application servers.

Application servers are usually very expensive machines from organizations like Sun and IBM and they usually cost over $20,000 apiece. And these application servers then talk to the corporate back ends such as databases. And your databases are usually things like Oracle.

Now, let's take a look at how all of this works. So you have a transaction going through. So you're going to a shopping site, you just get sent to an arbitrary web server. It then sends you along to an application server that's going to process logic and that logic will hold things like your shopping cart.

So this is where we remember what items you've purchased. And the application server, whenever it needs to find things like from the product catalogue, that's at what point it goes and talks to the database. And things like static content, you know, promotional materials and what have you come from the web servers.

So these are the three tiers of a three tier architecture: you have a web server tier that's sort of static content, you have an application server tier that stores things like your shopping cart information, and you have a data tier that stores information like the enterprise's corporate product catalogue and account information.

So there's a transition in the enterprise away from running expensive machines from organizations like Sun and IBM and more towards running commodity machines, so cheap machines like you're seeing here on the web tier. So what people are doing is, instead of running these expensive machines, they're switching to running cheap commodity machines on this tier as well, so no more expensive machines.

And now we're going to try to run our application servers, our J2E on these little machines. And generally, what you have to do is you have to kind of scope down what's running in an application server to really doing things like handling shopping carts, which is what most of them are doing anyway. So a lot of applications that you're running in your application tier are actually very, very suitable for running on small machines.

So this begs the question, why have a tier of commodity web servers mitigate connections to a tier of commodity application servers? At this point you have commodity machines mitigating connections to other commodity machines. And this is what brings us to lightweight architecture. Instead of running two different tiers here, what people are moving to is running one flat tier of commodity machines. So essentially, you add more machines to the web server tier and you start to do things like shopping carts here and you don't have to do them there.

So when your connection comes in you can get sent again to any arbitrary machine. If it needs the shopping cart, it'll just go get it from the neighbor and if it needs something from the corporate back end, it can go straight there, it can process straight through to the actual corporate enterprise back ends. And what's the benefit of this is this is an architecture very similar to what's been battle hardened by Google, Yahoo and Amazon and the next generation of Web 2.0 guys like FaceBook. Flicker or MySpace. These guys only run one large tier of commodity machines that talk to another tier of data back ends.

The benefit of running a two tier architecture instead of a three tier architecture is now you have one tier of cheap commodity machines communicating to your corporate back ends and you get to significantly decrease your cost. You are no longer running any big machines and you are no longer running two tiers. So you only have one tier of machines that you need to administer and provision. Now, beyond that you also get increased scalability because you can just continue-if you have your software configured correctly-you can continue to just add machines to this tier and scale linearly.

These are the benefits of running a lightweight architecture.