Data About Networking

1.1 Growth Of Computer Networking
Computer networking has grown explosively. Since the 1970s, computer communication
has changed from an esoteric research topic to an essential part of the infrastructure.
Networking is used in every aspect of business, including advertising, production,
shipping, planning, billing, and accounting. Consequently, most corporations have multiple
networks. Schools, at all grade levels from elementary through post-graduate, are
using computer networks to provide students and teachers with instantaneous access to
online information. Federal, state, and local government offices use networks, as do
military organizations. In short, computer networks are everywhere.
The growth and uses of the global Internet† are among the most interesting and exciting
phenomena in networking. In 1980, the Internet was a research project that involved
a few dozen sites. Today, the Internet has grown into a production communication
system that reaches all populated countries of the world. Many users have highspeed
Internet access through cable modems, DSL, or wireless technologies.
The advent and utility of networking has created dramatic economic shifts. Data
networking has made telecommuting available to individuals and has changed business
communication. In addition, an entire industry emerged that develops networking technologies,
products, and services. The importance of computer networking has produced
a demand in all industries for people with more networking expertise. Companies need
workers to plan, acquire, install, operate, and manage the hardware and software systems
that constitute computer networks and internets.
1.2 Introduction And Overview Chap
quired because all programmers are expected to design and implement application
software that can communicate with applications on other computers.
1.2 Why Networking Seems Complex
Because computer networking is an active, exciting field, the subject seems complex.
Many technologies exist, and each technology has features that distinguish it from
the others. Companies continue to create commercial networking products and services,
often by using technologies in new unconventional ways. Finally, networking seems
complex because technologies can be combined and interconnected in many ways.
Computer networking can be especially confusing to a beginner because no single
underlying theory exists that explains the relationship among all parts. Multiple organizations
have created networking standards, but some standards are incompatible with
others. Various organizations and research groups have attempted to define conceptual
models that capture the essence and explain the nuances among network hardware and
software systems, but because the set of technologies is diverse and changes rapidly,
models are either so simplistic that they do not distinguish among details or so complex
that they do not help simplify the subject.
The lack of consistency in the field has produced another challenge for beginners:
instead of a uniform terminology for networking concepts, multiple groups each attempt
to create their own terminology. Researchers cling to scientifically precise terminology.
Corporate marketing groups often associate a product with a generic technical term or
invent new terms merely to distinguish their products or services from those of competitors.
Thus, technical terms are easily confused with the names of popular products. To
add further confusion, professionals sometimes use a technical term from one technology
when referring to an analogous feature of another technology. Consequently, in addition
to a large set of terms and acronyms that contains many synonyms, networking
jargon contains terms that are often abbreviated, misused, or associated with products.

power generation cogeneration

In a bid to help reduce the environmental burden of waste disposal, municipalities across the nation are beginning to harness the energy that escapes into the atmosphere as heat during trash incineration. Inefficiency has long plagued this type of power generation, but new technologies are making the option attractive to the many plants that are now adopting them.
Plenty of Power from Garbage
Not surprisingly, waste incineration, like other forms of energy generation, involves using heat obtained by burning fuel to boil water; steam-driven turbines then generate electricity. What is surprising is the long history behind waste incineration. An Osaka incinerator was outfitted to produce electricity in 1965, and the late 1970s saw a similar operation by a Tokyo factory looking to sell power to electric utility companies. The practice has been growing steadily since then. Of the some 2,000 incinerators in the nation, 130 were producing a total of 640 megawatts of power, or an oil equivalent of 232,000 kiloliters, as of the end of March 1996. This is far more than the amount currently produced by solar power (400 kl) or wind power (1,000 kl).
Waste-incineration is a stable source of energy, being unaffected by changes in the weather as are solar and wind power. Moreover, other thermal, hydroelectric, and nuclear plants are generally built in remote places; as a result, the cost of getting the energy to the consumer is higher. Waste incinerators, however, have access to more fuel in highly populated areas, and large generators are easy to install. And the need to burn the trash at a constant temperature to produce a steady flow of power affords the additional benefit of reducing the amounts of dioxin and other dangerous substances produced.
There is a downside to this method of generating power, though. In general, the efficiency of thermal electricity production goes up along with the temperature of the steam. But garbage burned at high temperatures gives off chlorine and other corrosive gases that can damage the steam pipes. Steam produced by waste incineration is therefore kept between 250 and 300 degrees centigrade, giving the method an efficiency of only 15% to 16%, compared with close to 40% efficiency for other types of thermal power generation where the steam is heated to between 500 and 600 degrees. But recent technological developments are now making it possible to cope with this problem.
Toward More Efficient Generation
Two methods for boosting the efficiency of waste-incineration power have been developed. The first involves using more heat-resistant materials for the steam pipes in the plants. One incinerator in Saitama Prefecture that has been generating electricity since 1995 has been able to hike its efficiency to 21% by replacing its pipes with chlorine-resistant stainless steel conduits and boosting steam temperature to 380 degrees. The plant is now able to generate 720 kilowatts per ton of trash, as opposed to the 200 to 300 kilowatts that a normal incinerator is able to obtain.
The second technological development is a dual generating system involving both gas turbines and trash incineration. Turbines are powered by natural gas to produce electricity; the exhaust from the turbines, which reaches temperatures from 500 to 600 degrees, is then used to further heat the steam produced by the trash incinerator to about 400 degrees. This type of power plant, called a "super waste incinerator," has been generating electricity on a trial basis since the end of last year in both Gunma Prefecture and in the city of Sakai, Osaka Prefecture. Another "super" plant should go on line in Kitakyushu, Fukuoka Prefecture, in summer 1998. The Gunma dual-system plant is capable of producing 25 megawatts of electricity and has achieved an efficiency rate of over 30%.
These highly efficient waste-incineration power plants consume about 20% to 30% of their generated electricity themselves; the remainder is sold back to utility companies. One plant in Saitama Prefecture uses one-third of the 24 megawatts it generates and earns 1.3 billion yen (11.3 million dollars at 115 yen to the dollar) annually by selling the remaining two-thirds of the electricity. This is quite a difference from before the switch to high-efficiency equipment, when the plant paid 180 million yen (1.6 million dollars) each year for the power it needed.
Next on the drawing board are ways to reduce the cost of plant construction and make it easier to store electricity produced overnight until it can be used. As these new technologies are developed, the number of waste incinerators producing electricity is sure to leap.

from junk to juice

In a bid to help reduce the environmental burden of waste disposal, municipalities across the nation are beginning to harness the energy that escapes into the atmosphere as heat during trash incineration. Inefficiency has long plagued this type of power generation, but new technologies are making the option attractive to the many plants that are now adopting them.
Plenty of Power from Garbage
Not surprisingly, waste incineration, like other forms of energy generation, involves using heat obtained by burning fuel to boil water; steam-driven turbines then generate electricity. What is surprising is the long history behind waste incineration. An Osaka incinerator was outfitted to produce electricity in 1965, and the late 1970s saw a similar operation by a Tokyo factory looking to sell power to electric utility companies. The practice has been growing steadily since then. Of the some 2,000 incinerators in the nation, 130 were producing a total of 640 megawatts of power, or an oil equivalent of 232,000 kiloliters, as of the end of March 1996. This is far more than the amount currently produced by solar power (400 kl) or wind power (1,000 kl).
Waste-incineration is a stable source of energy, being unaffected by changes in the weather as are solar and wind power. Moreover, other thermal, hydroelectric, and nuclear plants are generally built in remote places; as a result, the cost of getting the energy to the consumer is higher. Waste incinerators, however, have access to more fuel in highly populated areas, and large generators are easy to install. And the need to burn the trash at a constant temperature to produce a steady flow of power affords the additional benefit of reducing the amounts of dioxin and other dangerous substances produced.
There is a downside to this method of generating power, though. In general, the efficiency of thermal electricity production goes up along with the temperature of the steam. But garbage burned at high temperatures gives off chlorine and other corrosive gases that can damage the steam pipes. Steam produced by waste incineration is therefore kept between 250 and 300 degrees centigrade, giving the method an efficiency of only 15% to 16%, compared with close to 40% efficiency for other types of thermal power generation where the steam is heated to between 500 and 600 degrees. But recent technological developments are now making it possible to cope with this problem.
Toward More Efficient Generation
Two methods for boosting the efficiency of waste-incineration power have been developed. The first involves using more heat-resistant materials for the steam pipes in the plants. One incinerator in Saitama Prefecture that has been generating electricity since 1995 has been able to hike its efficiency to 21% by replacing its pipes with chlorine-resistant stainless steel conduits and boosting steam temperature to 380 degrees. The plant is now able to generate 720 kilowatts per ton of trash, as opposed to the 200 to 300 kilowatts that a normal incinerator is able to obtain.
The second technological development is a dual generating system involving both gas turbines and trash incineration. Turbines are powered by natural gas to produce electricity; the exhaust from the turbines, which reaches temperatures from 500 to 600 degrees, is then used to further heat the steam produced by the trash incinerator to about 400 degrees. This type of power plant, called a "super waste incinerator," has been generating electricity on a trial basis since the end of last year in both Gunma Prefecture and in the city of Sakai, Osaka Prefecture. Another "super" plant should go on line in Kitakyushu, Fukuoka Prefecture, in summer 1998. The Gunma dual-system plant is capable of producing 25 megawatts of electricity and has achieved an efficiency rate of over 30%.
These highly efficient waste-incineration power plants consume about 20% to 30% of their generated electricity themselves; the remainder is sold back to utility companies. One plant in Saitama Prefecture uses one-third of the 24 megawatts it generates and earns 1.3 billion yen (11.3 million dollars at 115 yen to the dollar) annually by selling the remaining two-thirds of the electricity. This is quite a difference from before the switch to high-efficiency equipment, when the plant paid 180 million yen (1.6 million dollars) each year for the power it needed.
Next on the drawing board are ways to reduce the cost of plant construction and make it easier to store electricity produced overnight until it can be used. As these new technologies are developed, the number of waste incinerators producing electricity is sure to leap.

power generation

Hey Larry here,
If you’re looking for the best way to generate power at home, then I’m glad you’ve found this website and I strongly suggest you keep reading…
Because this is my uncensored home power generation story. The good, the bad, what stuff did not work and finally the one thing that did end up helping me achieve my main goal of home power generation.
Click here to see the website that showed me how to generate power at home.
I was tired of paying the high rates my energy company was demanding. Demanding because if I refuse to pay then they will shut off my power. I grew tired of being tied down to my local electric company and decided to do something productive about it.
I tried changing electric companies and was able to get a better rate. However, it’s not really much better otherwise. You are still locked into them for power supply and in most cases you are required to sign in for a 6 month or 12 month contract. I have heard of people “cheating” their power company but of course that is not something that I could do. I had also checked with some local retailers and learned that a basic solar installation could cost over $20,000 dollars. Can you beleive that? At this point, I just wasn’t sure what other options I had.
And then it happened. I stumbled across a “how to” product called Earth4Energy which really blew my mind. I hadn’t really thought much about home power generation and how that could solve my main problem of being locked in with the local electric company. This product actually showed me where to get the materials and how to build it all myself saving me a ton. It was actually kind of fun too! The only thing I didn’t really like about the Earth4Energy product was that the videos were kind of large and on my slow connection it took a while to download them all. I hope you found this useful and are thinking about looking into home power generation as it’s the way of the future. You can check it out:

electrical equipment

types of omputer virsus

Viruses can be catagorized in more than one way.  For example, they can be catagorized by their primary function and propagation method as follows:
Trojan horse--enters a system disquised as something else
Worm--propagates on its own by a variety of means including hijacking email accounts, user ids, file transfer programs, etc.
Bomb--doesn't propagate itself at all, is placed by a human or another program and activated by a trigger such as time or event. Usually does something unpleasant when it goes off.
Port Scanner--hides on a system and scans the surrounding environment for IP addresses and open ports that it then makes available to other malicious code or individuals.

The way viruses are usually catagorized however, is by what they do as follows:
Boot Virus--infects the boot sector of disk storage  (Form, Disk Killer, Michelangelo)
Program Virus--infects executable programs (Sunday, Cascade )
Multipartite Virus--combination of the first two (Invader, Flip, Tequila)
Stealth Virus--able to avoid detection by a variety of means such as removing itself from the system registry, masqarading as a system file, etc. (Frodo, Joshi, Whale)
Parasitic Virus--embeds itself into another file or program such that the orginal file is still viable (Jerusalem)
Polymorphic Virus--changes its code structure to avoid detection and removal, mutates (Stimulate, Cascade, Phoenix, Evil)
Macro Virus--exploits the macro language of a program like MSWord or MSExcel for malicious purpose (DMV, Nuclear, Word Concept)
Hope this is helpful