no need to memorize…

Last thursday, I had the last mid-term exam of my undergrad life, and first time in my life I decided to read the course book. I eventually caused my failure from the exam since reading 260 pages in 2 days was impossible. And see what I’ve focused in the book Here are some interesting foot-prints from the history of computer networks:cell phone networks

Finding locations high in the air to place base station antennas is a major issue. This problem has led some telecommunication carriers to forge alliances with the Roman Catholic Church, since the latter owns asubstantial number of exalted potential antenna sites worldwide, all conveniently under a single management

Invention of automatic switch:

In the early days of the telephone, the connection was made by the operator plugging a jumper cable into the input and output sockets. In fact, a surprising little story is associated with the invention of automatic circuit switching equipment. It was invented by a 19th century Missouri undertaker named Almon B. Strowger. Shortly after the telephone was invented, when someone died, one of the survivors would call the town operator and say ’Please connect me to an undertaker.” Unfortunately for Mr. Strowger, there were two undertakers in his town, and the other one’s wife was the town telephone operator. He quickly saw that either he was going to have to invent automatic telephone switching equipment or he was going to go out of business. He chose the first option.For nearly 100 years, the circuit-switching equipment used worldwide was known as Strowger gear. (History does not record whether the now-unemployed switchboard operator got a job as an information operator,answering questions such as ”What is the phone number of an undertaker?”)

Value of copper:

At one time, 80 percent of AT&T’s capital value was the copper in the local loops. AT&T was then, in effect, the world’s largest copper mine. Fortunately, this fact was not widely known in the investment community. Had it been known, some corporate raider might have bought AT&T, terminated all telephone service in the United States, ripped out all the wire, and sold the wire to a copper refiner to get a quick

payback.

Cadillacs going crazy

Sometimes omnidirectional radio is good, but sometimes it is bad. In the 1970s, General Motors decided to equip all its new Cadillacs with computer-controlled antilock brakes. When the driver stepped on the brake pedal, the computer pulsed the brakes on and off instead of locking them on hard. One fine day an Ohio Highway Patrolman began using his new mobile radio to call headquarters, and suddenly the Cadillac next to him began behaving like a bucking bronco. When the officer pulled the car over, the driver claimed that he had done nothing and that the car had gone crazy. For sure nobody believes him but in that year, it becomes a usual event in Ohio Highway. Later GM engineers realize that the wireless system that Ohio Highway Patrol use affects Cadillac’s computer controlled break system.

Were the king blessed by god?

A case could be made for redefining the foot as the distance light travels in a vacuum in 1 nsec rather than basing it on the shoe size of some long-dead king.

Does humankind have to solve any problem that he faces with an invention?

It is noteworthy that modern wireless digital communication began in the Hawaiian Islands, where large chunks of Pacific Ocean separated the users and the telephone system was inadequate.

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