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Ð ÐIt allows packets from many sources to share a single line, allowing for more efficient use of the communication
                   medium.

                 Ð ÐPackets are normally permitted onto the network on a first-come, first-served basis.
                 Ð ÐPackets are delayed or deleted if the network gets overcrowded (“dropped”).
                 Ð ÐThis type of data transport became the core networking technology that underpins the internet and most LANs.
                 Data Communication Terminologies

                 We know that data travels through the digital stream. The exchange of data between two or more networked or connected
                 devices is known as data communication. Let us now study the various terminologies related to data communication.
                 Channel

                 A communication channel is a medium that allows a message to be sent from one location to another. It could refer
                 to the entire physical media, such as a phone line, optical fibre, coaxial cable, or twisted pair cable, or it could refer to
                 one of the multiple carrier frequencies broadcasts simultaneously within the line.

                 We have three broad categories of communication channels based on their speed:

                 Ð ÐNarrow band: It is slow and used for telegraph lines and low speed terminals.
                 Ð ÐVoice band: It is used for regular telephone communication.
                 Ð ÐBroad band: It is the fastest and used for transmitting large amounts of data at high speeds.
                 Bandwidth
                 The range of frequencies available for data transmission in electronic communication is referred to as bandwidth. It
                 is measured in Hertz (Hz) as the difference between the highest and lowest frequencies. A normal voice signal, for
                 example, has a bandwidth of about 3KHz. The more bandwidth a communication system has, the more capacity it has,
                 and hence the more data that can be carried in a given amount of time.
                 Data Transfer Rate

                 The data transfer rate (DTR) is the amount of digital data transported from one location to another via a network in
                 a given amount of time. As previously said, the higher the data transfer rate, the greater the bandwidth of a given
                 medium. Although data transfer rate refers to digital data streams, it can also be referred to as throughput. Although
                 the unit baud, which is one bit per second, is also used, the data transfer rate is commonly measured in bits per second
                 (bps). It’s a standard metric for determining how quickly data is transported from one location to another. For example,
                 your Internet service provider may offer a 4Mbps maximum data transmission rate.

                   1.4 NETWORK TYPES

                 Networks are the backbone of today’s business, used for everything from accessing the Internet to printing a document
                 and to downloading an attachment from an email. They can refer to anything from a few gadgets in a single room to
                 millions of devices distributed across the globe, and they can be classified according to their purpose and/or size. On
                 the basis of geographical span, the network can be broadly categorized as follows:



                                                          Types of Computer Network





                              PAN                      LAN                     MAN                      WAN


                 Let us understand each one by one.


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