About DSL Internet Service

DSL is another digital internet connection and working with high speed than any old dial-up and cable modem.

       There is no need to install new dedicated cable network to run DSL because data is transmitted over already exiting copper wire.

This connection is ideal for internet access.

DSL provider offering traffic allowed up to 1 GB with basic 128 Kbps internet connection. 

But if you want to play online games, downloading audio or video files and uploading data, then the traffic allowed(1 GB) in one month from DSL provider will be the main issue for you.

                 May be some DSL provider offering you up to 2 GB or more with the same rates. Today there are many DSL providers offering DSL connection in all cities and some rural areas. DSL provides high speed on already exiting telephone lines, and same time you can use internet and as well as your line for phone. 

To check the availability of DSL connection first check your telephone number at which you are want to install DSL connection.

If your telephone exchange is updated by DSL provider according to need of DSL technology then you may apply for DSL internet connection. For this purpose you can visit your friends or neighbors for information to getting broadband connection.

You can visit your nearest Internet service provider to check DSL availability in your area and about different DSL packages.

DOS 6 point 22 internal commands

DOS 6.22 internal commands DOS (Disk Operating System) has 2 type of commands.

1. Internal DOS Commands.

2. External DOS Commands. 

In this article I am going to explain only DOS 6.22 internal commands.

DOS 6.22 based on 3 files.

1. Config.sys

2. Command.com

3. Io.sys

If you have these 3 files then DOS will boot using these 3 files.

These are called DOS 6.22 booting or boot files. 

All internal commands place in command.com file.

Dot com extension is executable in DOS 6.22. 

here are few DOS internal commands list.

Command Explanation and usage

DIR: This command is used to display the list of files in current directory or folder.

TIME: This command is used to display and change current system time.

DATE: This command is used to display and change current system date.

CLS: Clear the screens.

RENAME: Rename a file.

DEL or ERASE: Delete one or multiple files. 

COPY: Copy one or multiple files.

MOVE: Move one or multiple 

MD or MKDIR: Create new directory or folder.

CD or CHDIR: Change current folder or directory path.

RD or RMDIR: Remove an empty folder or directory.

PROMPT: To view or change current dos prompt.

VOL: To view hard disk volume or label.

ECHO: To display a message (DOS variables can be use with this command.)

SET: To view or change DOS variables list.

GOTO: To jump the cursor but only in Batch programming.

IF: To check condition but only in Batch programming.

PAUSE: To pause the process normally used in Batch programming.

VER: Displays the DOS version information. TYPE Display the contents of a file.

CALL: To call other file in Batch programming.

The Breif History Of Internet

The Internet is the network of networks around the world.

            It is made up of thousands of smaller, national, regional, governmental, academic and commercial networks.

It is a global network. Information can be communicated from one city (or country) to another through Internet.

         You can access information all over the work. More than two billion people around the world use the Internet daily for different purposes. 

For example, to communicate with other people around the world, access information and latest news around the world etc.

       The computers are the main components through which information can be electronically sent and received from one location to another.

For this purpose, a special device called modem is also used with computer and then computer is attached with the telephone line. The modem sends and receives the information over telephone lines. You must have an Internet connection of any local ISP (Internet Service Provider) to share the information on Internet.

The telephone lines, fiber-optic cables, satellite communications are the main media of communications that are used to connect to the Internet.

Today Internet is a global web of nearly one million computer networks. Internet host computers are connected to the Internet round the clock.

Brief History of Internet:

The Internet was started in 1969 by the defense department of USA. Later, it was handed over to the Defense Advanced Research Projects Agency (DARPA). The DARPA launched the first Internet program. The DARPA established a network of 4 computers and named as ARPANet.

    The protocols (Software) that define the rules to exchange information between computers were created by DARPA.

The idea of computer networking soon became popular. Several universities & research organizations developed their own computer networks. They joined their networks to ARPANet. The ARPANet became the network of networks. This network of computer networks was named as Internet.

In 1986 the National Science Foundation (NSF), another federal agency of USA, established a network and named as NSFNet. It was established for academic purpose and was accessible to everyone. Later, it was expanded all over the country and large number of universities and research centers were connected to this network.

The academic networks were established and all these were interconnected together to share the information. The way of connecting one network to another is termed as internetworking and “Internet” is also derived from internetworking. The NSF provided the connections for academic research centers only.

                 After this many telecommunication companies established their own network backbones by using the same networking protocol as NSFNet used and also provided connections to private users. In 1995, NSF terminated its network on the Internet. Today, the Internet consists of many local, regional, national and international networks.

Network Backbone:

The inner structure of the Internet works much like a transportation system. The main communication lines carry the heaviest amount of traffic on the Internet. These communication lines are referred to as Internet backbone. It can also be defined as:

The central structure or element of the network, which connects other elements of the network and handles the major traffic, is called the backbone. The backbone is a high-speed element. It is the major communication link that ties Internet servers across wide geographical areas.

How the Internet works?

It must be noted that there is no particular organization that controls the Internet. Different networks of private companies, government agencies, research organizations, universities etc. are interconnected together. You can say that the Internet is a huge collection of millions of computers, all linked together on a computer network. The network allows all of the computers to communicate with one another.

           A home computer may be linked to the Internet using a phone-line modem, DSL or cable modem that communicates to an Internet Service Provider (ISP). A computer in a business or university will usually have a network interface card (NIC) that directly connects it to a Local Area Network (LAN) inside the business. The business can then connect its LAN to an ISP using a high-speed phone line such as Ti Line. A Ti Line can handle approximately 1.5 million bits per second, while a normal phone line using a modem can typically handle 30,000 to 50,000 bits per second.

Accessing the Internet

The Internet can be accessed through different ways to send and receive information.

The most popular methods are:

Connecting through Modem
Connecting through a LAN
Connecting through high-speed lines

1. Connecting through a Modem

You can connect to the Internet through modem. In this way, serial data communication port and dial-up utility program is used.

Most of the individual users connect to the Internet by using a telephone line, a modem of 56 Kbps and a SLIP (Serial Line Interface Protocol) or PPP (Point—to—Point Protocol) account. Most of the ISP companies provide these types of connections for home users and businesses.

When you connect to the ISP’s server computer by dialing through a telephone number, you have to give your username, password provided by that ISP Company.

2. Connecting through a LAN

You can connect to the Internet through a LAN, if LAN uses TCP/IP protocols and has an Internet connection.

This type of connection is commonly used by business to provide the LAN’s users with Internet access. Actually, the computer on the LAN connects to the Internet.

through a router. If the LAN uses a different kind of protocol then a gateway is used to convert that protocol to and from TCP/IP.

3. Connection through High Speed Lines

The data accessing speed of modem connection is very slow. It fine to access text data but it is not suitable to access graphics files or data like audio and video.

Today connections of dedicated high-speed lines are available from different telephone companies, cable 1W services etc. You can access data with very high speed, i.e., 20 or more times faster by using fiber optics, microwaves, satellites etc.

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Online Communication

Uses of Online Communication There are many uses of online communication but the most popular uses of online communication are described below.

Internet Telephony Internet teulephony enables users to talk over the Internet.

The Internet telephone software is available to use the Internet telephony. When the user speaks into a microphone, the Internet telephone software and computer’s sound card convert the sound signals into digital signals and transmit them over the Internet to the called person.

  Software and devices used at the receiver’s end receive the signals and convert to analog signals so the receiving person can hear your voice.

                      Internet Printing Today, network printers are also available having web addresses built into them. The user cast send a print job to the network printer from anywhere in the world.

A printer with Internet capability can also receive print jobs from desktop computers, mobile computers or devices and smart phones. Many hotels and Airlines use the Internet printing. Collaboration Much software provides a means to work (or collaborate) online with other users connected to a server.

The users can also conduct online meetings with Microsoft Office XP.

An online meeting allows users to share documents with others in real time. It means that all the participants can see the document at the same time. You can also type and send messages to others etc.

Workgroup & Workgroup Computing In a computer network, people can work together online as a group even when they are thousands of miles away from each other. This concept of working together is called workgroups. Therefore workgroup may be defined as a group of people (or individuals) working together on a given project and sharing information via computer networks.

A group of people can share work together by means of linked computers. The phenomenon of sharing information by various members of workgroup is called Workgroup Computing. The members of workgroup, who are thousands of miles away from each other cannot only share information but can also talk to each other on a computer network while seeing each other as they talk.

They can also send and receive messages to each other. Global Positioning System (GPS) Global Positioning Systems (GPSs) help to create maps, locating and monitoring people and objects. These systems are also used in new cars to provide directions and other information.

A Global Positioning System (GPS) consists of one or more earth-based receivers that accept and analyze signals sent by satellite(s) and determine the receiver’s geographic location. A GPS receiver is a handheld or embedded device that contains an antenna, a radio receiver, a processor, and a display screen that shows an individual’s location on a map. Short Message Service (SMS) Short Message Service (SMS) is a means for smart phone, cellular telephone, or PDA users to send and receive shod text messages. Most SMS messages have a limit of about 160 characters per message. SMS was introduced in 1995. SMS is used for business and social purposes. When a user sends a message, a SMS center receives it and routes it to the appropriate smart phone, cellular telephone, or PDAs.

If the receiver’s phone is out of range or inactive, the SMS center holds onto the message and delivers it when that one becomes active.

Advantages and Disadvantages of Internet

Advantages:

            The Internet provides many facilities to the people. The main advantages of Internet are discussed below.

1. Sharing Information You can share information with other people around the world. The scientist or researchers can interact with each other to share knowledge and to get guidance etc. Sharing information through Internet is very easy, cheap and fast method.

2. Collection of Information A lot of information of different types is stored on the web server on the Internet. It means that billions websites contain different information in the form of text and pictures. You can easily collect information on every topic of the world. For this purpose, special websites, called search engines are available on the Internet to search information of every topic of the world. The most popular search engines are altavista.com, search.com, yahoo.com, ask.com etc. The scientists, writers, engineers and many other people use these search engines to collect latest information for different purposes. Usually, the information on the Internet is free of cost. The information on the Internet is available 24 hours a day.

3. News You can get latest news of the world on the Internet. Most of the newspapers of the world are also available on the Internet. They have their websites from where you can get the latest news about the events happening in the world. These websites are periodically updated or they are immediately updated with latest news when any event happens around the world.

4. Searching Jobs You can search different types of jobs all over the world, Most of the organizations/departments around the world, advertise their vacant vacancies on the Internet. The search engines are also used to search the jobs on Internet. You can apply for the required job through Internet.

5. Advertisement Today, most of the commercial organizations advertise their product through Internet. It is very cheap and efficient way for the advertising of products. The products can be presented with attractive and beautiful way to the people around the world.

6. Communication You can communicate with other through Internet around the world. You can talk by watching to one another; just you are talking with your friends in your drawing room. For this purpose, different services are provided on the Internet such as; Chatting Video conferencing E-mail Internet telephony etc.

7. Entertainment Internet also provides different type of entertainments to the people. You can play games with other people in any part of the world. Similarly, you can see movies, listen music etc. You can also make new friends on the Internet for enjoyment.

8. Online Education Internet provides the facility to get online education. Many websites of different universities provide lectures and tutorials on different subjects or topics. You can also download these lectures or tutorials into your own computer. You can listen these lectures repeatedly and get a lot of knowledge. It is very cheap and easy way to get education.

9. Online Results Today, most of the universities and education boards provide results on the Internet. The students can watch their results from any part of country or world.

10. Online Airlines and Railway Schedules Many Airline companies and Pakistan Railway provide their schedules of flights and trains respectively on the Internet.

11. Online Medical Advice Many websites are also available on the Internet to get information about different diseases. You can consult a panel of online doctors to get advice about any medical problem. In addition, a lot of material is also available on the Internet for research in medical field.

Disadvantages:

                           Although Internet has many advantages but it also has some disadvantages. The main disadvantages are:

1. Viruses Today, Internet is the most popular source of spreading viruses. Most of the viruses transfer from one computer to another through e-mail or when information is downloaded on the Internet. These viruses create different problems in your computer. For example, they can affect the performance of your computer and damage valuable data and software stored in your computer.

2. Security Problems The valuable websites can be damaged by hackers and your valuable data may be deleted. Similarly, confidential data may be accessed by unauthorized persons.

3. Immorality Some websites contains immoral materials in the form of text, pictures or movies etc. These websites damage the character of new generation.

4. Filtration of Information When a keyword is given to a search engine to search information of a specific topic, a large number of related links a displayed. In this case, it becomes difficult to filter out the required information.

5. Accuracy of Information A lot of information about a particular topic is stored on the websites. Some information may be incorrect or not authentic. So, it becomes difficult to select the correct information. Sometimes you may be confused.

6. Wastage of times A lot of time is wasted to collect the information on the Internet. Some people waste a lot of time in chatting or to play games. At home and offices, most of the people use Internet without any positive purpose.

7. English language problems Most of the information on the Internet is available in English language. So, some people cannot avail the facility of Internet.

About Search Engine

Search engines are the special websites that provide facility to Internet users to search information on the Internet.

             A lot of information is available on the Internet in different websites. There are billions of websites on the Internet. The Internet users only browse the important website addresses.

The other website addresses can be searched through search engines. The search engines keep the record of website addresses along with important words for description of each web page.

For example, if you want to get information about the “History of Internet”, give these words to any search engine. The search engine will search the given information and will provide a list of links of websites along with brief description about each website.

Click one of the links of websites after reading the description.

The commonly used search engines and their URL addresses are:

GOOGLE http://www.google.com

YAHOO http://www.yahoo.com 

ALTA VISTA http://www.altavista.com

ASK http://www.ask.com

EXCITE http://www.excite.com

INFOSEEK http://www.infoseek.com LYCOS http://www.lycos.com