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The word ‘computer‘ originally implied a person, who, under instructions from a mathematician, performed mechanical calculations. Mechanical calculating devices such as the abacus were often put to use to aid this process.

At the end of the Middle Ages, mathematics and engineering in Europe received a considerable boost, thus leading to the invention of numerous mechanical calculating devices. The technology for clockwork was developed by the early 17th century. The period between the early 19th century and early 20th century saw the development of a number of technologies which would be vital for the development of the digital computer later on. Some examples are the punched card and the valve. Charles Babbage was the first person to design a fully programmable computer as early as 1837. However, he was unable to actually construct his computer due to a variety of reasons.

Analog computers were increasingly used in the first half of the 20th century for a number of scientific computing needs. However, they became obsolete after the development of the digital computer.

The first digital computer was the Atanasoff Berry Computer . It used a binary system of arithmetic, parallel processing, a separation of memory and computing functions and regenerative memory. Binary math and electronic circuits - both of which are used in today’s computers - were first used in the Atanasoff Berry Computer.

In the 1930’s and 1940’s, newer and more efficient computers were continuously developed. Gradually, they came to possess the key features which are present in modern day computers - digital electronics and flexibility of programming.

Among the more important machines to be developed during this time, the American ENIAC was prominent. It was a general purpose machine, but had an inflexible architecture. Later a far superior technique known as the stored program architecture was developed. It is the foundation from which all modern computers are derived.

Throughout the 1950’s, computer design was primarily valve driven. This was later replaced by transistor-driven design in the 1960’s. Transistor-based computers were smaller, faster and cheaper, and hence commercially viable. Integrated circuit technology, adopted in the 1970’s enabled computer production costs to hit a new low, so that even individuals could afford them. That was the birth of the personal computer, as it is known today.

Logan writes about various topics. This article is free to re-print as long as all hyper links remain in tack and the rel=”nofollow” tag isn’t added to any links. Thank-You http://www.your-personal-pc.info

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Many small businesses have considered connecting computers and other devices to their corporate network via wireless (WiFi) connections, and a brave few have actually done so. Many of these early networks required that wireless devices be carefully placed within the building so that the wireless signal reached all intended recipients. Typically, these networks lacked adequate security features, which left them vulnerable to information and resource theft by unauthorized persons. These two problems have now been largely solved, meaning that it may be time for more small businesses to look into the potential advantages a wireless network can offer.

Wireless Networking Basics

Building a wireless network requires two distinct types of hardware components, wireless access points, and wireless access cards. The wireless access point is a device, which is attached to an existing computer network via a standard Ethernet cable. It has an antenna on it, which allows it to broadcast and receive signals from PCs and other devices. Each device wishing to communicate with the access point needs a wireless access card, which also contains an antenna. The current wireless standard, called 802.11g, allows for up to 54 megabits of data per second to be transmitted between the desired access point and the access card. While not quite as fast as wired networks, which typically run at 100 megabits to 1000 megabits per second, wireless networks offer more flexibility, and can be less expensive to install. This is especially true for older buildings where installing cable can become cost prohibitive.

Cutting Corners

Wireless networks use radio frequency waves to transmit information, and thus they are susceptible to being blocked by walls and other obstructions in a building. These obstructions can cause “dead zones” where the radio waves are unable to reach their intended recipients. Microwave ovens and other radio frequency emitting devices can also wreak havoc on wireless signals. The solution is to place your wireless access points strategically around your building so that interference is minimized. When the distance from a wireless access point to the wireless device is more than a few dozen meters, wireless repeaters can be installed to boost the signal. These repeaters can also be placed so that the wireless signals can be accessible from all corners of the building.

Wireless Network Security Solved

Installing a simple wireless network is pretty straightforward, but installing a secure wireless network can be substantially more difficult. However, an Ann Arbor company called Interlink Networks now offers their LucidLink products, which make installing comprehensive wireless network security a snap. Before LucidLink became available, an organization wishing to lock down their wireless network would need to hire expensive network security consultants to install and manage the wireless portion of the network. LucidLink packages all of this expertise into a software add-on that is so easy to use that even a small company’s office manager can easily take control over who is accessing the company network via wireless. It goes above and beyond simple address authentication (standard with most wireless routers), and implements what is called a RADIUS server. RADIUS servers are what large organizations spend thousands of dollars installing and maintaining in order to secure their large (1000+ node) wireless networks. Until now, installing a RADIUS server was out of the price range for all but the largest companies. In contrast, LucidLink’s product can be purchased for as little as $99 for a 3 user Home Office Edition, $449 for a 10 user version, and goes up to $3995 for a 250 user version.

Summary

While there are still issues with making sure that all areas of a building are covered, the current WiFi standard (802.11g) has a more powerful signal, meaning less emphasis needs to be placed on the locations of attached devices. However, it is still recommended that a professional site survey be done to verify that all required areas of the building can be reached by the wireless signal. Meanwhile, Interlink Networks has finally solved the security problem at a price that is affordable for small and medium sized business.

Terrence A. Weadock is the President and Founder of Dominant Systems Corporation, an Ann Arbor-based computer network solutions provider.
http://www.domsys.com

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