Introduction to Operating Systems:History The 1970s

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The 1970s

The systems of the 1970s were primarily multimode multiprogramming systems that supported batch processing, timesharing and real-time applications. Personal computing was in its incipient stages, fostered by early and continuing developments in microprocessor technology.43 The experimental timesharing systems of the 1960s evolved into solid commercial products in the 1970s. Communications between computer systems throughout the United States increased as the Department of Defense’s TCP/IP communications standards became widely used—especially in military and university computing environments.44, 45, 46 Communication in local area networks (LANs) was made practical and economical by the Ethernet standard developed at Xerox’s Palo Alto Research Center (PARC).47, 48 In Chapter 16, Introduction to Networking, we discuss TCP/IP, Ethernet and fundamental net- working concepts.

Security problems increased with the growing volumes of information passing over vulnerable communications lines (see the Anecdote, Abraham Lincoln’s Technology Caution). Encryption received much attention—it became necessary to encode proprietary or private data so that, even if the data was compromised, it was of no value to anyone other than the intended receivers. In Chapter 19, Security, we discuss how operating systems secure sensitive information from unauthorized access. During the 1970s, operating systems grew to encompass networking and security capabilities and continued to improve in performance to meet commercial demands.

The personal computing revolution began in the late 1970s with such systems as the Apple II, and exploded in the 1980s.

Self Review

1. What developments in the 1970s improved communication between computer systems?

2. What new problem was introduced by the increased communication between computers?

How was this problem addressed?

Ans: 1) The DoD’s TCP/IP standards became widely used in network communications— primarily in university and military computing environments. Also, Xerox’s PARC developed the Ethernet standard, which made relatively high-speed local area networks (LANs) practi- cal and economical. 2) Communication between computers introduced security problems because data was sent over vulnerable communication lines. Encryption was employed to make data unreadable to anyone other than the intended recipient.

Anecdote

Abraham Lincoln’s Technology Caution

The story goes that during the Civil War one of President Lincoln's young lieutenants came running up to him eager to speak with the President. “What is it, lieutenant?” “Mr. President, Mr. President, we are wiring the battlefields for this wonderful new technology called the telegraph. Do you know what that means, Mr. President?” “No lieutenant, what does it mean?” “Mr. President, it means we'll be able to make decisions at the speed of light!” The older and wiser President Lincoln looked down at the lieutenant and said calmly, “Yes, lieutenant, but we'll also be able to make wrong decisions at the speed of light!”

Lessons to operating systems designers: Every new technology you will evaluate has its pros and cons. You will inevitably spend a great deal of your time concerned with performance issues. But, making things happen faster may have unpleasant consequences.

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