Hi, name is Peter Yared, CEO of ActiveGrid. Today I'm goingI'm going to talk to you about lightweight architecture. Lightweightarchitecture is a new way to run computing applications across large clustersof commodity machines. Today the Fortune 500 runs three tier architecture, solet's look at what three tier architecture is and how it can scale into alightweight architecture.
So the way three tier architecture works is you have a tierof web browsers, and these are machines just like your machines at home andthey communicate to an enterprise. Now, the enterprises runs a cluster of webservers and these web servers are one to two-way commodity machines from placeslike Dell that generally cost less than $2,000. These web servers thencommunicate to a tier of application servers.
Application servers are usually very expensive machines fromorganizations like Sun and IBM and they usually cost over $20,000 apiece. Andthese application servers then talk to the corporate back ends such asdatabases. And your databases are usually things like Oracle.
Now, let's take a look at how all of this works. So you havea transaction going through. So you're going to a shopping site, you just getsent to an arbitrary web server. It then sends you along to an applicationserver that's going to process logic and that logic will hold things like yourshopping cart.
So this is where we remember what items you've purchased.And the application server, whenever it needs to find things like from theproduct catalogue, that's at what point it goes and talks to the database. Andthings like static content, you know, promotional materials and what have youcome 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 applicationserver tier that stores things like your shopping cart information, and youhave a data tier that stores information like the enterprise's corporateproduct catalogue and account information.
So there's a transition in the enterprise away from runningexpensive machines from organizations like Sun and IBM and more towards runningcommodity 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, sono 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 youhave to kind of scope down what's running in an application server to reallydoing things like handling shopping carts, which is what most of them are doinganyway. So a lot of applications that you're running in your application tierare actually very, very suitable for running on small machines.
So this begs the question, why have a tier of commodity webservers mitigate connections to a tier of commodity application servers? Atthis point you have commodity machines mitigating connections to othercommodity machines. And this is what brings us to lightweight architecture.Instead of running two different tiers here, what people are moving to isrunning one flat tier of commodity machines. So essentially, you add moremachines to the web server tier and you start to do things like shopping cartshere and you don't have to do them there.
So when your connection comes in you can get sent again toany arbitrary machine. If it needs the shopping cart, it'll just go get it fromthe neighbor and if it needs something from the corporate back end, it can gostraight there, it can process straight through to the actual corporateenterprise back ends. And what's the benefit of this is this is an architecturevery similar to what's been battle hardened by Google, Yahoo and Amazon and thenext generation of Web 2.0 guys like FaceBook. Flicker or MySpace. These guysonly run one large tier of commodity machines that talk to another tier of databack ends.
The benefit of running a two tier architecture instead of athree tier architecture is now you have one tier of cheap commodity machinescommunicating to your corporate back ends and you get to significantly decreaseyour cost. You are no longer running any big machines and you are no longerrunning two tiers. So you only have one tier of machines that you need toadminister and provision. Now, beyond that you also get increased scalabilitybecause you can just continue-if you have your software configuredcorrectly-you can continue to just add machines to this tier and scalelinearly.
These are the benefits of running a lightweightarchitecture.
