Cloud Computing - Part 2 - Architecture

When talking about a cloud computing system, it's helpful to divide it into two sections: the front end and the back end. They connect to each other through a network, usually the Internet. The front end is the side the computer user, or client, sees. The back end is the "cloud" section of the system.
The front end includes the client's computer (or computer network) and the application required to access the cloud computing system. Not all cloud computing systems have the same user interface. Services like Web-based e-mail programs leverage existing Web browsers like Internet Explorer or Firefox. Other systems have unique applications that provide network access to clients.


On the back end of the system are the various computers, servers and data storage systems that create the "cloud" of computing services. In theory, a cloud computing system could include practically any computer program you can imagine, from data processing to video games. Usually, each application will have its own dedicated server.

A central server administers the system, monitoring traffic and client demands to ensure everything runs smoothly. It follows a set of rules called protocols and uses a special kind of software called middleware. Middleware allows networked computers to communicate with each other.

If a cloud computing company has a lot of clients, there's likely to be a high demand for a lot of storage space. Some companies require hundreds of digital storage devices. Cloud computing systems need at least twice the number of storage devices it requires to keep all its clients' information stored. That's because these devices, like all computers, occasionally break down. A cloud computing system must make a copy of all its clients' information and store it on other devices. The copies enable the central server to access backup machines to retrieve data that otherwise would be unreachable. Making copies of data as a backup is called redundancy.

Cloud Computing - Part 1

I decided to start this Cloud Computing series on my blog as part of my research on the subject. This is Part 1 and I'm not really sure how many parts it's going to be finally but I hope to cover the essentials.
If you are new to the world of Cloud and would like to get a quick overview this is probably useful to you.
So what exactly is Cloud computing?
Cloud computing is processing on the web, think of it as your local community center where resources are shared e.g. you and your neighbors use the pool and pay the fee but you don't maintain it. These shared resources are provided to computers and devices and they are done on demand which I think is the most critical part of it. So if you don't need to use the resources someone else can use them, the sharing makes them more efficient.
Details of the underlying system are all abstracted from the end user. End users do not own the physical infrastructure of the system and pay only for resources used. This kind of abstraction ensures that businesses can focus on core business and allow the IT infrastructure to be managed by a third party.
The major Cloud service providers today are Google, Amazon and Salesforce. I will go into details of each of these vendors and their offerings in future posts.

Cloud computing basic architecture
The basic architecture of Cloud computing involves a front end and a back end. The front end is what is seen by the end user. The front end includes the end user's network and the applications used to access the cloud with a web browser or other interface. The back end of the cloud is comprised of various servers, data storage systems etc. The front end usually communicates with the back end using web services.

That's all I have in the way of introduction. In the next few parts I shall go into details of the different layers of cloud computing, deployment models and issues faced. I hope you continue to read...

Google Apps

Recently I had the good fortune of listening to this webcast of how the City of Westerville, Ohio moved to Google Apps, replacing Novell GroupWise. Of course they went through a pilot phase and tested out the solution for their email systems.

Their biggest savings have been IT infrastructure costs because guess what everything is routed through google now and they need not worry about maintaining servers, upgrading, licensing etc.

At this point if you are wondering what google apps are then it is a good time to check this link:

Google Apps

I was very impressed with the fact that putting your email system on the google cloud would mean a big performance improvement right away. For the City of Westerville, it took away the need for internal spam check and vastly improved performance. There was a slight increase to bandwidth use however but that was made up by other benefits.

Some concerns I have are security but goggle has been addressing that diligently.

The email system also integrates with Microsoft Outlook if you are looking for a non-web solution.

Google Apps are already targeting government organizations and they have a specific platform for them. The price of using the apps is $50/person/year which would greatly reduce costs for an organization. Having consulted with a city agency for a long time, I think it would greatly benefit such organizations as it would free up resources invested in IT infrastructure projects for other more important projects.