Enterprise Computing: Clouds, grids and Software as a service

[pinkpapaver]

so a cloud is just another word for server? makes it sound all the more mysterious then when all it is is a whirring machine powered by steam.

 

[knock]

so a cloud is just another word for server? makes it sound all the more mysterious then when all it is is a whirring machine powered by steam.

Not quite, cloud computing is mostly about virtualisation. If you've ever used something like VMWare or Virtualbox that's virtualisation. A powerful server - a "host" - is divided into several virtual servers - the "guests". Deploying a new server, traditionally a job involving heavy lifting and waiting for hardware to arrive becomes a few clicks of a mouse. An overloaded system can be upgraded without leaving your desk. Typically an organisation will have several hosts, and the guests can be moved from one to another. If a guest requires more processing power or memory than is available on its host you can move it to an underused host. You need to have a reasonably large number of hosts available for this to be practical.

Because the physical location of your guest servers is largely irrelevant and may change from day to day, the hardware is visualised as a cloud. Where's your server? don't know don't care, it's somewhere in the cloud. It's a buzzword that doesn't explain itself but there are some actual useful technologies behind it.

 

[parttime crackhead]

Ah, fair does. I thought it was literally just marketing speak for a server.

 

[Ceres]

cloud computing really is just clustered infrastructure but they couldn't call it that incase people started to referring to it as a cluster fuck. Which is what the horseshit talked about it really is ;P It is useful though, especially when combined with virtualisation.

 

[knock]

Just in case :D

Looks like I might have mislead you a little, cloud computing is actually just the use of services without awareness of their physical location. For example, it's possible for a company to have email, word processing, spreadsheets, and other software systems hosted by several companies, accessed over the internet. That's the cloud, although a cloud can also be a private thing within an organisation. I wasn't just talking randomly about virtualisation, though - it's the key enabling technology...

People often ask what is the real difference of cloud computing and “the internet” or “ isn’t the internet already cloud computing”. I often tell them that cloud computing does not equal the internet or vice-versa, the internet is simply the best delivery platform that cloud computing can make use of. You can have a cloud computing infrastructure totally isolated from the internet and it is called a private cloud network. Still, some private cloud networks are made to be accessible via the internet, but the argument still stands that cloud computing does not automatically mean or require the internet.

What makes cloud computing itself is not the hardware technology or the infrastructure, what makes it cloud computing is the way that services and functions are being handled and delivered. In essence what cloud computing means is that everything is being done by a server that is located somewhere that you and I should really not concern ourselves anymore, it’s somewhere out there, “in the clouds”. Behind all the services and applications that are labeled as “cloud” are servers, lots and lots of servers where all the processing elements are, the CPU, RAM, GPU, and even the storage devices. However, a server is only really able to dedicate itself to one task, application, or function and serve that over a local network or typically via the internet. This is very limiting for cloud computing as you would need a lot of servers for multiple applications, taking up space, producing heat, and soaking up electricity like sponges. The answer to this is the whole point of the article, server virtualization.

The problem is that a server can only serve one purpose so you would need more of them. So as I mentioned, the answer is server virtualization, the creation of multiple “virtual” servers via software and using only one or few real server hardware to do it. A powerful server can create hundreds of virtual servers with each having its own hardware specification like CPU speed, RAM size, and storage capacity. And each one of these virtual servers can be put to a single use, providing they do not all require vast amounts of computing power. This means that we are able to host multiple applications and services on a single or small group of physical servers, a very efficient use of hardware resource.

Virtualization is very important for cloud computing and as a result brings another benefit that cloud computing is famous for, scalability. Because each virtual server is allocated only enough computing power and storage capacity that the client needs, more virtual servers can be created. But if the needs grow, more power and capacity can be allocated to that server, or lowered if needed. And because clients only pay for how much computing power and capacity they are using, this can be very affordable for most clients.

Without virtualization, cloud computing as we know it would not exist or would be in a different form. But such is now only in the realm of speculation as virtualization is really here to make Information Technology more affordable for the world.

Ceres reading my mind although I'm not sure how central clustering is - that's important in Grid computing. But I suppose a load of virtual servers is by definition a cluster.

I think the main thing is, it's just a way to make IT management more flexible, not very exciting to the end user.

 

[Ceres]

see,this is what i was talking about a while ago in another thread when I mentioned how dual boot is old hat and I run multiple virtualised OS's at home on my computer at the same time, it speeds up productivity no end, especially when you have shared storage across them. Doesn't have to be anything to do with the internet. There is a lot of hot air talked about all this when companies are trying to flog services to people, I really don't like subscription based software (it's a ripoff business model just like itunes is and so on,don't let them con you. adobe can get lost with their subscription based move for CS, I'll just stop upgrading and stick to my pirate copies thanks). What if your internet connection goes down and suddenly all your software stops working and your remote storage is offline....? Don't believe the hype!

 

[knock]

I tend to agree, it's a good way to make piracy impossible, and it takes power out of the hands of end users. But it can make sense for companies who don't want to worry about managing IT, or who want a flexible infrastructure.