The first day of the EGEE’08 Business Track delved into the latest hype of cloud computing. Discussions have started on what it is, who is it for and should everyone really have their head in the clouds? In an attempt to avoid being in the same position as we were not too long ago and attempting to define the word “Grid”, I will not do the same for cloud. But what I will do is offer a few suggestions of how some experts in the field feel how we can at least explain to those who might not be exactly too sure what cloud means and some of the current benefits and issues.
Forrester offered clouds as a pool of abstracted highly scalable, and managed compute infrastructure capable of hosting end-customer applications and billed by consumption. Another offered by IGT, which was agreed to be a simplistic enough that it just might work, was “pay-per-use for on demand scalability”.
Clouds offer many benefits, but like all technology it not fool proof and is not necessarily appropriate for all. Cloud offers a simple interface to allow end-users to pay for only what they use (roughly $0.10 CPU/hour). This is highly attractive from an economic standpoint to allow companies avoiding to pay for an expensive IT infrastructure when high utilization maybe be only once a month (processing payroll or billing). It offers scalability and flexibility of resources as well.
On the other hand, cloud has been referred as “not for the faint-of-tech”. Other barriers arose regarding legal issues as some countries (e.g. Canada) need to know the location of the data center where the data is being stored (e.g. cannot be stored in US).
To date, there are a variety of different cloud offers available such as VM Based (EC2, GoGrid); Storage Based (EMC, S3); Customers Applications based (Google); Cloud Applications based (SalesForce); Grid Computing/HPC/GPGPU Applications; Mobile Clouds (iPhone UI, WEB APPS). There are even private clouds or just to throw out another term, Ultra Modular Computing, basically an internal cloud; and finally Cloud of Clouds.
So what does this mean for grid, rendering it obsolete? Well no, cloud offers an opportunity to developers to run grid applications on top of the underlying architecture. Since this is not a one size fits all technology, then standard grid solutions are still valid and relevant depending on the requirements.
I do not believe that this is a competition between grid and cloud, but both need to be understood in their separate rights as well as similarities between to leverage off any new and potentially game changing technologies.
The above points definitely do not cover all points and could lead to some opposing viewpoints, which I full-hearted welcome. Please feel free to expand on any of the above points as well.