Computer Network Protocols 4th Grade 2023-2024 PDF

Computer Network protocols 4th Grade 2023-2024 Dr. Mohammed Hasan Ali  Physical TRANSMISSION MEDIA 1. Guided Data is sent via a wire or optical cable. Twisted Pair Two copper wires are twisted together t...

Computer Network protocols 4th Grade 2023-2024 Dr. Mohammed Hasan Ali  Physical TRANSMISSION MEDIA 1. Guided Data is sent via a wire or optical cable. Twisted Pair Two copper wires are twisted together to reduce the effect of crosstalk noise. Unshielded Twisted-Pair (UTP) cables Shielded Twisted-Pair (STP) cables Baseband Coaxial Cable A 50-ohm cable used for digital transmission. Used in 10Base2 and 10Base5. Broadband Coaxial Cable A 75-ohm cable used for analog transmission such as Cable TV. Fiber Optic Cables Two general types are multimode and single mode. In multimode, light is reflected internally. Light source is an LED. In single mode, the light propagates in a straight line. Light source come from expensive laser diodes. Faster and longer distances as compared to multimode. 2. Unguided Data is sent through the air. Line-of-sight Transmitter and receiver must ―see‖ each other, such as microwave system. Communication Satellites A big microwave repeater in the sky. Data is broadcasted, and can be ―pirated. Radio Term used to include all frequency bands, such as FM, UHF, and VHF television. ANALOG TRANSMISSION 1. Modulation Modulating a sine wave carrier to convey data. Amplitude Modulation (AM) Amplitude is increased/decreased while frequency remains constant. Frequency Modulation (FM) Frequency is increased/decreased while amplitude remains constant. Phase Modulation(PM) Wave is shifted, while amplitude and frequency remains constant. Physical Devices& Transmission 1. Modems A device that accepts digital signals and outputs a modulated carrier wave, and vice versa. It is used to interconnect the digital computer to the analog telephone network. 2.RS-232 and RS-422 well known physical layer standards. 3.Encoding Schemes 4. Repeaters and Hubs  SONET\SDH Networks  Synchronous Digital Hierarchy (SDH) is European standard network.  It is a standard developed by ITU-T.  Synchronous Optical Network (SONET) is American standard network  (SONET) is a standard developed by ANSI for fiber-optic networks.  Both are used as a transport network to remove loads from other WANs. SONET is defined as a hierarchy of signals called synchronous transport signals (STSs). Each STS level (STS-1 to STS-192) supports a certain data rate, specified in megabits per second SDH is defined as a similar hierarchy of signals called synchronous transfer modules (STMs). BLUETOOTH  Bluetooth is a wireless LAN technology designed to connect devices of different functions such as telephones, notebooks, computers (desktop and laptop), cameras, printers, and even coffee makers when.it was originally started as a project by the Ericsson Company. Architecture Bluetooth defines two types of networks: 1.Pico net. 2. scatter net. A Bluetooth network is called a Pico net, or a small net. A Pico net can have up to eight stations, one of which is called the primary; the rest are called secondary's.