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              Features of Packet Switching
              Some of the common features of packet switching technique are as follows:

              Ð ÐEach packet has a “header” that provides information needed to route it from source to destination.
              Ð ÐPackets take shortest path as possible to travel across the network.
              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”).
               ÐThis type of data transport became the core networking technology that underpins the internet and most LANs.
              Ð
              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


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