TELECOMMUNICATION AND NETWORK topologies
- 2. Communication is the transmission, transfer, or distribution of telephone service and related activities. Telecommunication, also known as telecom, is the exchange of information over long distances using electronic means, such as voice, data, and video transmission. Telecommunication is composed of two words- technology and communication.
- 3. Telecommunications, also known as telecom, is the exchange of information over significant distances by electronic means and refers to all types of voice, data and video transmission. This is a broad term that includes a wide range of information-transmitting technologies and communications infrastructures. Examples include wired phones, cellphones, microwave communications, fiber optics, satellites, radio and television broadcasting, the internet and telegraphs. A complete, single telecommunications circuit consists of two stations, each equipped with a transmitter and a receiver. The transmitter and receiver at any station might be combined into a single device called a transceiver. The medium of signal transmission can be via electrical wire or cable -- also known as copper -- optical fiber, electromagnetic fields or light. The free space transmission and reception of data by means of electromagnetic fields is called wireless communications.
- 4. History of telecommunications The word telecommunications comes from the Greek prefix tele-, which means "distant," combined with the Latin word communicare, which means "to share.“ Important telecommunication technologies include the telegraph, telephone, radio, television, videotelephony, satellites, closed computer networks and the public internet.
- 5. History • Telegraph • Telephone • Computer • Transistor • Large-Scale Integrated Circuits • Satellite
- 6. •1876. The first telephone was invented by Alexander Graham Bell. This early model required an interpreter, or telegrapher, at both ends. These first telephones were intercom systems, where two phones were connected directly. •1877. The invention of the switchboard exchange telephone system enabled any combination of two phone lines to connect and talk with each other. •1891. Dial telephones were invented, which bypassed the need for an operator on each call. This made it much quicker and easier to make calls via telephone. •1947. The transistor was invented, which led to the development of modern electronics, such as computers and calculators. •1948. Microwaves began to be used to transmit phone signals, in places where phone wires did not exist. •1960. Phones began to transition from mechanical switching to electronic switching, which enabled features such as voice messaging, speed dialing and caller ID. •1984. The Bell System, which provided AT&T with a near-monopoly over telecommunications services in the U.S., was broken up, opening space for competition for other providers. •1984. Cellular and personal communications service phone use, which offered mobile communications beyond two-way radio use, was introduced. •1990s. Use of the modern internet became widespread. •2000s and beyond. The first decade of the 2000s saw mobile phones grow increasingly sophisticated. By 2012, smartphone usage was widespread.
- 20. NETWORKING Networking, or computer networking, is the process of connecting two or more computing devices, such as desktop computers, mobile devices, routers or applications, to enable the transmission and exchange of information and resources. Networked devices rely on communications protocols—rules that describe how to transmit or exchange data across a network—to share information over physical or wireless connections. Before contemporary networking practices, engineers would have to physically move computers to share data between devices, which was an unpleasant task at a time when computers were large and unwieldy. To simplify the process (especially for government workers), the Department of Defense funded the creation of the first functioning computer network (eventually named ARPANET) in the late 1960s.
- 21. Key networking components and devices Before we delve into more complex networking topics, it’s important to understand fundamental networking components, including: •IP address: An IP address is the unique number assigned to every network device in an Internet Protocol (IP) network; each IP address identifies the device’s host network and its location on the network. When one device sends data to another, the data includes a “header” that includes the IP addresses of both the sending and receiving devices. •Nodes: A node is a network connection point that can receive, send, create or store data. It’s essentially any network device—computers, printers, modems, bridges or switches—that can recognize, process and transmit information to another network node. Each node requires some form of identification (such an IP or MAC address) to receive access to the network. •Routers: A router is a physical or virtual device that sends data “packets” between networks. Routers analyze the data within packets to determine the best transmission path and use sophisticated routing algorithms to forward data packets until they reach their destination node. Switches: A switch is a device that connects network devices and manages node-to-node communication across a network, making sure that data packets reach their intended destination. Unlike routers, which send information between networks, switches send information between nodes within a network. Consequently, “switching” refers to how data is transferred between devices on a network. •Ports: A port indicates a specific connection between network devices, with each port identified by a number. If an IP address is analogous to a hotel address, then ports are the suites and room numbers. Computers use port numbers to determine which application, service or process should receive which messages. •Gateways: Gateways are hardware devices that facilitate communication between two different networks. Routers, firewalls and other gateway devices use rate converters, protocol translators and other technologies to make inter-network communication possible between otherwise incompatible devices.
- 22. A computer network is a connection between two or more network devices, like computers, routers, and switches, to share network resources. The establishment of a computer network depends on the requirements of the communication channel, i.e., the network can be wired or wireless.
- 23. TYPES Typically, computer networks are defined by geographical area. A local area network (LAN) connects computers in a defined physical space, while a wide area network (WAN) can connect computers across continents. However, networks are also defined by the protocols they use to communicate, the physical arrangement of their components, how they manage network traffic and the purpose they serve in their respective environments.
- 24. 1. Personal Area Network (PAN) PAN is the most basic type of computer network. It is a type of network designed to connect devices within a short range, typically around one person. It allows your personal devices, like smartphones, tablets, laptops, and wearables, to communicate and share data with each other. PAN offers a network range of 1 to 100 meters from person to device providing communication. Its transmission speed is very high with very easy maintenance and very low cost. This uses Bluetooth, IrDA, and Zigbee as technology. Examples of PAN are USB, computer, phone, tablet, printer, PDA, etc.
- 25. •Personal Area Network is a network arranged within an individual person, typically within a range of 10 meters. •Personal Area Network is used for connecting the computer devices of personal use is known as Personal Area Network. •Thomas Zimmerman was the first research scientist to bring the idea of the Personal Area Network. •Personal Area Network covers an area of 30 feet. •Personal computer devices that are used to develop the personal area network are the laptop, mobile phones, media player and play stations.
- 26. Types of PAN •Wireless Personal Area Networks: Wireless Personal Area Networks are created by simply utilising wireless technologies such as WiFi and Bluetooth. It is a low-range network. •Wired Personal Area Network: A wired personal area network is constructed using a USB.
- 27. 2. Local Area Network (LAN) LAN is the most frequently used network. A LAN is a computer network that connects computers through a common communication path, contained within a limited area, that is, locally. A LAN encompasses two or more computers connected over a server. The two important technologies involved in this network are Ethernet and Wi-fi. It ranges up to 2km & transmission speed is very high with easy maintenance and low cost. Examples of LAN are networking in a home, school, library, laboratory, college, office, etc.
- 28. 3. Campus Area Network (CAN) CAN is bigger than a LAN but smaller than a MAN. This is a type of computer network that is usually used in places like a school or colleges. This network covers a limited geographical area that is, it spreads across several buildings within the campus. CAN mainly use Ethernet technology with a range from 1km to 5km. Its transmission speed is very high with a moderate maintenance cost and moderate cost. Examples of CAN are networks that cover schools, colleges, buildings, etc.
- 29. 4. Metropolitan Area Network (MAN) A MAN is larger than a LAN but smaller than a WAN. This is the type of computer network that connects computers over a geographical distance through a shared communication path over a city, town, or metropolitan area. This network mainly uses FDDI, CDDI, and ATM as the technology with a range from 5km to 50km. Its transmission speed is average. It is difficult to maintain and it comes with a high cost. Examples of MAN are networking in towns, cities, a single large city, a large area within multiple buildings, etc.
- 30. 5. Wide Area Network (WAN) WAN is a type of computer network that connects computers over a large geographical distance through a shared communication path. It is not restrained to a single location but extends over many locations. WAN can also be defined as a group of local area networks that communicate with each other with a range above 50km. Here we use Leased-Line & Dial-up technology. Its transmission speed is very low and it comes with very high maintenance and very high cost. The most common example of WAN is the Internet.