In the timesharing model of mainframe computing, each user was granted a fixed slice of the resource pie (compute and storage) with which to perform tasks. The system kept a record of the actual resource usage of each terminal, which was then printed out at the end of each session. The report detailed the following: CPU seconds, storage I/O ops, and total number of storage blocks used. Timesharing proved to be a very effective way to grant computer access to multiple users, at a time when computing was a very expensive endeavor.

 

When I was in college, in the late 70’s and early 80’s, computer timesharing was the dominant method my fellow students and I would use to access the campus mainframe, which was locked away somewhere in a university data center. We would go to one of the 30 or so terminals in the computer lab, each of which was connected back to the mainframe. From our individual terminals, we were each granted a small time-slice of the mainframe’s CPUs to write programs, run them, and play games.

 

Gradually, businesses began to recognize the value that timesharing provided, by allowing many users to share one computer. A new type of company was born, the Service Bureau, whose sole purpose was to provide computer timesharing services to other companies. This represented the first major adoption of computing in the corporate world. Over time, Moore’s Law began to kick in, reducing the price and complexity of computers to a point where businesses could afford to invest in their own hardware. The need for Service Bureaus quickly began to diminish.

 

By the mid 1980s, just as quickly as they had arrived, most of the Service Bureaus were gone or had moved on to other ventures as companies absorbed the functions they once provided. This transition, from externally hosted third party computing to internal data centers, represented a major shift in consciousness by the entire business world. Suddenly, companies began to realize that this “thing” called a computer was really good at doing many of the tasks businesses needed to complete on a daily basis. One example of this, payroll processing, was turned into a very efficient computer-automated process by companies such as ADP. As time passed, businesses came to depend on computers for an ever increasing share of their day-to-day operations.

 

The story of the last 30 years of corporate computing has played out as a series of paradigm shifts like the one described above. During this gradual evolution process, companies have retained the lessons learned from previous technologies and paradigms, such as ERP and timesharing, while continuing to move forward to meet the needs of an ever more challenging business climate. Learnings of the past are now taken for granted by a business community with its sights set on the here and now. 

 

Each of these shifts was the result of a new business need, and a corresponding technology which was best able to meet that need. Like those times, now is a time of great challenges for business, with needs that a different than those of the past. Through this series of posts, I intend to outline the new problems faced by business users in the current IT landscape, the ways that cloud computing and outsourced IT addresses these problems, and the other residual benefits cloud users stand to gain. As you read, keep in mind the challenges faced by your organization, and how they can potentially be solved in the cloud.

(parts 2 and 3 of this article have been included in the May 2010 ACM Communications article that Dave Durkee wrote on "Why Cloud Computing Will Never Be Free" and is available from ENKI on request.)