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welcome to our course. Let's start our course by answering this question. What is a computer letter?
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The definition of a computer network is simply as follows. It's a group of computers that are sometimes called hosts or notes and a group off computer peripherals that are all connected together via transmission media and some connecting devices.
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All of these elements form what we call a computer network.
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The types off computers have changed it.
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Nowadays, we have laptops, tablets, smart mobile phones.
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We usedto have only personal computers, or peces that were also called desktop computers. Nowadays, we have others that are mobile and that can transfer and send and receive information over the network.
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can now be connected toe a computer network through peces through laptops, tablets, smart mobile phones and threw water school the embedded systems inside, some off the electrical or mechanical machines. Yes,
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some of these machines can send and transfer and exchange data and information between each other
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transparently without the interference or the interaction off the human users. In order to offer a certain service for him with his minimal or with the least interaction from his side.
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This concept is known as Internet of things.
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Internet of things allows things machines to exchange information between each other in order to offer a certain service required by human users.
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that can be connected to a computer are simply
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The printer's, the scanners, the storage media.
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All of these are called
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These professionals can also be connected to a computer network as senders and as receivers off information
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and orders from the computer users
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to execute something that he wants to be done.
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Printers, scanners and storage media can be directly connected to the computer network and be part of it
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toe act as sources and destinations off data being transferred.
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If we have a look inside a cloud computing or a data center,
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we can see some servers, some storage devices and some terminals that are used for managing and configuration off the devices. Inside this cloud, computing or data centers,
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all of these can be seen as connected through transmission media in a local network. Inside the center
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toe offer a certain type of service required by the computer users, either infrastructure as a service or platform as a service or software. The service.
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This newly introduced concept is known as the Cloud Computing Concepts, and that is
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mainly depending on computer networks.
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The transmission media.
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The transmission media used by a computer network can be the wired media, the cables or the wireless media using air as the transmission media,
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The cables can be made off copper or can be made or fiber optic
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copper cables can either be co axial cables or twisted pair cables and in turn, that Western pear cables can either be shielded cables or unshielded cables, either STP Sheila Twisted pair or you TP cables. Unshielded twisted pack.
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The fiber optic cables does not transmit electricity. It transmits light
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light moves in the fiber optic cables in the form off single mode light or multi mode light. The difference between single mode and multi mode is in the capacity and the speed off
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the wireless transmission media using air
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depends mainly on a specified frequency band and a certain area or distance off coverage.
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Every wireless technology differs from the other in the utilized frequency band, and they utilized area off coverage or the distance between
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the sender and receiver covered by this wireless network.
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Every wireless technology has a name, the band and a limited and known area off coverage
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toe transfer data across
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the benefit off connecting computers through a network
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mainly lies in resources trading
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resources, either hardware or software
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Hardware resource is like the computers. Reference. Printers, scanners and other preference that can be connected to computers can also be shared through a computer network.
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One copy off the printer can serve 10 users instead off buying 10 copies off printers. To serve these 10 users we hear save money, Safe Coast, save effort and also safe time
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through one copy off the hardware that can be shared
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toe many users. The storage media can act
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one storage media can store for several users. The processing Power one
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supercomputing multi processor server
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the processing off several computers. If shared through the network,
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the software resources that can be shared through the network can be a file that can be copied and pasted over the letter that can be shared between two devices Over the Net.
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It can be a database database off students that can be shared through professors database off employees shared through the
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accounting the portmanteau calculate their
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salaries and their bonuses.
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Applications also can be shared over the Net. Turkey. They are also software Resource is
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an example of an application. The simplest example is a game, a game that can be played by several users over the letter. This is an application that is used over the network by several users, and in real time
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service is service is that can be offered over. The network can be
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the browsing service,
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searching for information over the network
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and exchanging email messages across the user's off the writer.
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These are the most commonly used. Service is
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also establishing voice schools, and video conference is over. The network are one off the
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common uses off a computer network inside an enterprise.
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The basic network elements are mainly the end devices. These are
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the communicating devices, the senders and the receivers, the sources and the distillations off information.
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These are the target off the network to communicate with each other.
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Other devices exist inside the network as intermediate devices as connecting devices such as the switches, the rotors and the excess points. Such devices are not meant to be sources or destinations off information, but they are acting as
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transferring entities for the information
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toe help or facilitate it
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these information across the Net.
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The medium used through the information network
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specifies how these devices are connected. Are they connected in a wired way or in a wireless way? Are they going to use the cables or the air as the media off connection
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messages? The messages are the information that are needed to be traveling through the network needed to be transferred needed to be
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communicated from the sender. Tow the receiver messages are also the target off the existence off computer network. We establish computer network to transfer messages
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across the end devices through human users.
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The protocols off a computer network
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rules and governs how the information is transferred.
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The protocols are the agreements and are the standards that every
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device either connecting were and device should follow and should take care off when dealing with information inside the computer network.
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Hopefully, we have now answered what a computer network is.