Cloud Computing (Part one)

Something is happening today in the world of computing. Data and programs are being swept up from desktop PCs and corporate server rooms and installed in “the compute cloud.” Whether it’s called cloud computing or on-demand computing, software as a service, or the Internet as platform, the common element is a shift in the geography of computation. When you create a spreadsheet with the Google Docs service, major components of the software reside on unseen computers, whereabouts unknown, possibly scattered across continents. The shift from locally installed programs to cloud computing is just getting under way in earnest. Some substantial fraction of computing activity is migrating away from the desktop and the corporate server room. The change will affect all levels of the computational ecosystem, from casual user to software developer, IT manager, even hardware manufacturer.

The new regime is not quite a return to the hub-and-spoke topology of time-sharing systems, if only because there is no hub. A client computer on the Internet can communicate with many servers at the same time, some of which may also be exchanging information among themselves. However, even if we are not returning to the architecture of time-sharing systems, the sudden stylishness of the cloud paradigm marks the reversal of a long-standing trend. Where end users and corporate IT managers once squabbled over possession of computing resources, both sides are now willing to surrender a large measure of control to third-party service providers.

What brought about this change in attitude? For the individual, total control comes at a price. Software must be installed and configured, then updated with each new release. The computational infrastructure of operating systems and low-level utilities must be maintained. Every update to the operating system sets off a cascade of subsequent revisions to other programs. Outsourcing computation to an Internet service eliminates nearly all these concerns. Cloud computing also offers end users advantages in terms of mobility and collaboration.

For software vendors who have shifted their operations into the cloud, the incentives are similar to those motivating end users. Software sold or licensed as a product to be installed on the user’s hardware must be able to cope with a baffling variety of operating environments. In contrast, software offered as an Internet-based service can be developed, tested, and run on a computing platform of the vendor’s choosing. Updates and bug fixes are deployed in minutes. (But the challenges of diversity don’t entirely disappear; the serverside software must be able to interact with a variety of clients.) Although the new model of Internet computing has neither hub nor spokes, it still has a core and a fringe.

The aim is to concentrate computation and storage in the core, where high performance machines are linked by high-bandwidth connections, and all of these resources are carefully managed.

(Courtesy: ACM Communications July 2008)

YOUTUBE VIDEO LECTURES ON CLOUD COMPUTING

1. Cloud Computing – Introduction

2. What is Cloud Computing

3. The Future of Operating System – Cloud Computing?