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What is a Computer Network? Definition, Types, Examples what is a computer network? If you run a business, you’ll know how important a computer network is. Not only does it allow staff to share information effortlessly, but it also plays a key role in increasing flexibility, reducing costs, and ma...
What is a Computer Network? Definition, Types, Examples what is a computer network? If you run a business, you’ll know how important a computer network is. Not only does it allow staff to share information effortlessly, but it also plays a key role in increasing flexibility, reducing costs, and making your business more efficient. But as technology evolves, networking does too. While networking used to be a bunch of desktop computers connected by wires and cables, these days networking includes wireless systems and connections and other advanced technologies. So what does a computer network mean in 2024, and how does it impact how computers communicate with each other within a computer system? This article delves into the meaning of a computer network, exploring its types and benefits while giving real-life examples of computer networks in action. What is a Computer network? Definition - A computer network is a system that connects two or more computing devices together so they can communicate and share resources. These devices include everything from a mobile phone to a server and can be connected through physical wires such as fibre topics, or entirely wirelessly via WiFi. - Devices in a computer network act as network nodes, interacting with each other through a set of standardized communication protocols. Networks come in various sizes and structures, ranging from a simple home network with your PC and printer to huge internet backbones spanning the globe. - The primary purpose of a computer network is to enable communication and data exchange between different devices, allowing them to work together efficiently. - Networks allow us to share all sorts of things, like files, printers, and even processing power. For example, you might have a printer on your network that everyone in your office can use, or you might be part of a network that allows you to access powerful computers to run complex calculations. Read: What is Computer Architecture? Definition, Types, Structure. What was the First Computer network? The first computer network was the ARPANET, which was Developed in the late 1960s by a branch of the US Department of Defense called the Advanced Research Projects Agency (ARPA). The US Department of Defense wanted a communication system resilient to attack, one that could survive even if parts of the network were destroyed. Traditional centralized systems were vulnerable, so researchers turned to a new idea: decentralization. This ARPANET pioneered the use of packet switching, a revolutionary technology that breaks down data into smaller packets and sends them over the network independently. This ensured efficient routing and redundancy, making the network resilient to disruptions. arpanet first computer network ARPANET, the first computer network. It also introduced the TCP/IP protocol suite, a set of communication protocols that laid the foundation for the Internet's open and interoperable architecture. ARPANET served as a testbed for various networking technologies, including email, file transfer protocols, and early forms of online chat, and led to the development of the internet by providing the infrastructure and technical groundwork for its expansion. How does a computer network work? A computer network is made up of devices called nodes, which can be any computer equipment like your PC or a printer. For the devices to understand each other, they use a common set of rules called communication protocols. These protocols define how information is formatted, transmitted, and received. Each device on the network has a unique address, similar to a home address, called an IP address. This address helps identify and locate specific devices when they need to communicate. Networks also often rely on special devices like routers and switches to manage the flow of data. Routers act like traffic police, directing information to the correct destination on the network, while switches efficiently connect devices within a network. The internet itself is a giant network of interconnected networks. Think of it as a web of smaller networks linked together, allowing devices all over the world to communicate and share information. What are the components of a computer network? components of computer network Computer networks are complex systems made up of several key components working together seamlessly. They’re built with two basic components – network devices and links. These links connect two or more nodes in a way that is defined by communication protocols. As well as these basic building blocks, several key components of computer networks are required to keep devices connected to the network. These include: 1. Nodes In a computer network, nodes are the individual devices that act as the origin, destination, or intermediate point for data communication. They can be any electronic equipment that can send, receive, or forward information, including computers, smartphones, printers or even smartphones. 2. Network interface cards (NICs) NICs act as the translator and connection point for a device on a network. They provide the physical port (wired or wireless) for a device to connect to the network cable or Wi-Fi signal and convert data from the device's format into a format suitable for transmission over the network and vice versa. NICs also play a role in managing the flow of data entering and leaving the device. 3. Transmission cables/signals In a computer network, transmission cables and signals act as the information highway. They physically carry the data (electrical or light pulses) between network devices like computers and routers. These signals represent the 0s and 1s that make up digital information. 4. Networking devices Networking devices are specialized hardware units that handle data flow and network management. They include: Hubs: Simple devices that broadcast data to all connected nodes, used in smaller networks. Switches: Forward data only to the intended recipient, improving network efficiency. Routers: Direct data packets between different networks, enabling communication across larger spans. Firewalls: Security devices that filter incoming and outgoing traffic to protect the network from unauthorized access. These can be open-source firewalls or closed-source firewalls. Modems: Translate signals between digital data and analogue formats for communication over telephone lines or cable lines. 5. Network Operating Systems (NOS) Traditionally, Network Operating Systems (NOS) were the main software managing resources on a network, facilitating file sharing, printers, and security for multiple devices network. Today, most modern operating systems include built-in networking features, reducing the need for separate NOS. However, NOS can still be relevant for centralized management within a network, offering a central point to manage user accounts, security, and network resources. 6. Protocols Protocols in a computer network act as the common language for devices. They're a set of rules that define how data is formatted, transmitted, and received, ensuring devices from different manufacturers and with varying software can understand each other. They define everything from data formatting and transmission to error detection and correction. Common protocols include TCP/IP, UDP, and Ethernet. Types of computer networks types of computer networks 1. Local Area Network (LAN) A Local Area Network (LAN) is essentially a private network connecting devices in a limited geographical area, like a home, office, or school. It’s a type of computer network that connects devices like computers, printers, and servers to enable them to share resources and data. It also provides a platform for users to access centralized services like file servers, printers, and the internet (if connected to a wider network). 2. Personal Area Network (PAN) A Personal Area Network (PAN) is a miniature network designed for interconnecting electronic devices within a short range, typically around a person's workspace. PANs usually operate within a few meters, and connect personal electronic devices like smartphones, laptops, tablets, wearables, and even printers for data exchange. PANs don't inherently provide internet access, but a connected device within the PAN might be able to share its internet connection They’re also limited to a few centimetres or meters depending on the technology used (Bluetooth, Wi-Fi Direct, etc.). 3. Wide Area Network (WAN) A Wide Area Network (WAN) is a type of computer network that spans a large geographical area. WANs typically connect multiple LANs together, allowing users and devices across different locations to share resources and communicate with each other. WANs Leased lines, VPNs, and satellite connections are some of the technologies used to establish WAN connections. They’re mos commonly used for Sharing files, applications, and other resources across locations. They also Facilitate communication among employees in different offices through email, video conferencing, etc. 4. Metropolitan Area Network (MAN) A Metropolitan Area Network (MAN) bridges the gap between Local Area Networks (LANs) and Wide Area Networks (WANs). It covers a metropolitan area, typically a large city, multiple towns, or a university campus, and connects multiple LANs within this geographical region so they can communicate and share resources at high speeds. MANs primarily rely on high-bandwidth technologies like fibre optic cables to ensure efficient data transmission. They can be owned and operated by a single entity (like a university) or by multiple organizations collaborating for a shared network infrastructure. MANs are ideal for institutions, businesses, and government agencies spread across a city or region that require high-speed data exchange and resource sharing. Examples of Computer Networks Examples of computer networks can be found all around you, designed to serve different purposes. Some of the most common, real-life examples of computer networks include: 1. Your home network Connecting your laptop, smartphone, printer, and smart TV allows you to share files, print documents, and stream content across devices. Bluetooth headphones. Wirelessly connecting your phone to your headphones is a PAN example. 2. School or office network. Connecting computers, printers, and servers within a building allows resource sharing and internet access for employees or students. 3. Cafe with free Wi-Fi. This allows customers to connect their laptops or phones to the internet for browsing, working, or streaming. ATM network. Connecting ATMs across a bank's network to allow customers to access their accounts from various locations. 4. Cloud Computing Network Cloud service providers like Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform (GCP) host a multitude of virtual servers and services. 5. Smart City Network A smart city implements smart infrastructure, such as traffic management systems, surveillance cameras, and environmental sensors connected through a network. These are just a few examples of computer networks in action. As technology advances, the ways we connect devices and create networks will continue to evolve and shape our world. What are Analog and Digital Signals? – Definition, Difference, Examples May 1, 2023 In this article, let us understand the basic and certain advanced concepts of analog and digital signals and their definitions. While we delve deeper into analog signals vs digital signals, we travel an extra mile to read the characteristics of analog and digital signals. A signal is an electrical or electromagnetic quantity that transports data or information from one system to another. For data transmission, two types of signals are used: Analog signals and digital signals. Analog and digital signals are very different in many ways. An analog signal is a continuous function, whereas a digital signal is a discontinuous function. Typically speaking, analog and digital signals are two signal kinds that carry data or information. As far as analog signal vs digital signal is concerned, analog signals feature continuous electrical signals, whereas digital signals are otherwise without continuity in signals. Types of Signals Signals are classified into two types: Continuous-time signals/ Analog signals: A continuous-time signal is any continuous function of time. Discrete-time signals/ Digital Signals: A discrete-time signal is any series of real numbers separated by equal time increments (or samples). What are analog signals? Analog signals are used to create information-carrying signals in a variety of systems. Both in terms of quantities and time, these signals are continuous. As technology evolved, digital transmissions repealed the use of analog signals. Signals that are natural or occur naturally are analog signals. Since it denotes a quantity that is analogous to another measure, it is called so. Analog signals are known for use of medium to channelize the flow of information. Analog signals can be easily distorted, thereby losing clarity and quality. Examples of Analog Signal Any natural sound, human voice, and data read by analog devices are examples of analog signals. Characteristics of analog signals Analog signals denote a voltage or any physical quantity that is continuous and invariable and fluctuates in its quantity based on the parameter whose behavior changes according to time. These can be radio waves, broadcast waves Further classification of analog signals based on characteristics: Continuous-time signals and discrete-time signals Analog signal processing makes use of the electronic devices to conduct several operations on the signals. These can be ranging from amplification to limiting. Certain tools used in processing analog signals are analog signal generators, power supply, oscilloscopes and certain other electronic equipment. Measuring analog signals For an analog signal source, its amplitude is measured in volts while the frequency of an analog signal is measured in Hertz. Thus, analog signals carry three categories of information – amplitude, frequency and phase What is Digital Signal? A digital signal is one that is a discrete function of time rather than a continuous signal. Digital signals are binary in nature and consist of discrete voltage values at discrete times. A digital signal, in essence, represents data and information as a sequence of discrete values at any given time. The digital signal has a limited number of values. Characteristics of digital signals The digital signal is a discrete delivery time and is a non-continuous signal. The bandwidth of digital signals is very high so, they are highly suitable for functions such as computing, digital operations, data storage, etc. The square wave function represents digital signals. These digital signals have fewer fluctuations, healthier instability, and do not fall prey to noise and disturbances, unlike analog signals. The accuracy and precision of digital signals is also high due to the zero effect of sound on them. They also use less power and give zero errors Difference between Analog Signals and Digital Signals The table below highlights all the key differences between Analog and digital transmissions. Parameter Analog Signal Digital Signal Analog signals are used to A digital signal transmits data in a Definition communicate information in a discrete function of time. continuous function of time. Analog signals represent data and Digital signals use discrete values 0 Signal values information using a continuous and 1. range of values. Signal bandwidth The bandwidth is low. The bandwidth is high. The digital signals are appropriate Analog signals are better suited for for computer and digital electronic Suitability transmitting audio, video, and other processes such as data storage and data via communication channels. other things. Effect of electronic Analog signals are easily influenced Digital signals are more reliable and noise by electrical noise. resistant to noise than Analog ones. Because analog signals are more As digital signals are noise-free, they Accuracy susceptible to noise, their accuracy have high accuracy. is reduced. Analog transmissions require more Digital transmissions utilize less Power consumption power to transmit data. power than analog signals. Resistors, capacitors, inductors, and Circuit components Transistors, logic gates, ICs, etc. other components Temperature, current, voltage, Data storage in computer memory is Examples voice, pressure, and speed are all one of the examples of digital examples of analog signals. signals. Used in landline phones, Used in computers, keyboards, Applications thermometers, radios, and other digital watches, and other electronic devices. devices. Conclusion There are many additional challenging topics and chapters in Physics that may be difficult to grasp. Join Physics Online home tuition Programs offered by the Tutoroot platform, it provides several benefits such as low pricing, access to the top educational guides, experienced personnel, doubt-clearing sessions, and many more. FAQs What are Examples of Analog Signals? Current and voltage, pressure, speed, voice and temperature, etc. What are Examples of Digital Signals? Digital computers, phones, and data storage are some of examples of digital signals Define Analog Signal Analog signals are used to create information-carrying signals in a variety of systems. Both in terms of quantities and time, these signals are continuous. As technology evolved, digital transmissions repealed the use of analog signals. Signals that are natural or occur naturally are analog signals. Since it denotes a quantity that is analogous to another measure, it is called so. Analog signals are known for the use of the medium to channel the flow of information. Analog signals can be easily distorted, thereby losing clarity and quality. Define Digital Signal A digital signal is one that is a discrete function of time rather than a continuous signal. Digital signals are binary in nature and consist of discrete voltage values at discrete times. A digital signal, in essence, represents data and information as a sequence of discrete values at any given time. The digital signal has a limited number of values. What are the differences between an analog signal and a digital signal? Analog signals are used to communicate information in a continuous function of time while a digital signal transmits data in a discrete function of time. Analog signals represent data and information using a continuous range of values while digital signals use discrete values 0 and 1. The bandwidth of analog signal is low while it is high for a digital signal. Analog signals are better suited for transmitting audio, video, and other data via communication channels. The digital signals are appropriate for computer and digital electronic processes such as data storage and other things. Analog signals are easily influenced by electrical noise. Digital signals are more reliable and resistant to noise than the analog ones. Because analog signals are more susceptible to noise, their accuracy is reduced, whereas, since digital signals are noise-free, they enjoy a higher accuracy. Analog transmissions require more power to transmit data. Digital signals on the other hand, utilize less power than analog signals. Types of Network Topology Network topology refers to the arrangement of different elements like nodes, links, and devices in a computer network. It defines how these components are connected and interact with each other. Understanding various types of network topologies helps in designing efficient and robust networks. Common types include bus, star, ring, mesh, and tree topologies, each with its own advantages and disadvantages. In this article, we are going to discuss different types of network topology their advantages and disadvantages in detail. Types of Network Topology The arrangement of a network that comprises nodes and connecting lines via sender and receiver is referred to as Network Topology. The various network topologies are: 1-Point to Point Topology 2-Mesh Topology 3-Star Topology 4-Bus Topology 5-Ring Topology Point to Point Topology Point-to-point topology is a type of topology that works on the functionality of the sender and receiver. It is the simplest communication between two nodes, in which one is the sender and the other one is the receiver. Point-to-Point provides high bandwidth. Point-to-point-topology Point to Point Topology Mesh Topology In a mesh topology, every device is connected to another device via a particular channel. In Mesh Topology, the protocols used are AHCP (Ad Hoc Configuration Protocols), DHCP (Dynamic Host Configuration Protocol), etc. Mesh Topolgy Mesh Topology Figure 1: Every device is connected to another via dedicated channels. These channels are known as links. Suppose, the N number of devices are connected with each other in a mesh topology, the total number of ports that are required by each device is N-1. In Figure 1, there are 5 devices connected to each other, hence the total number of ports required by each device is 4. The total number of ports required = N * (N-1). Suppose, N number of devices are connected with each other in a mesh topology, then the total number of dedicated links required to connect them is NC2 i.e. N(N-1)/2. In Figure 1, there are 5 devices connected to each other, hence the total number of links required is 5*4/2 = 10. Advantages of Mesh Topology - Communication is very fast between the nodes. - Mesh Topology is robust. - The fault is diagnosed easily. Data is reliable because data is transferred among the devices through dedicated channels or links. - Provides security and privacy. Disadvantages of Mesh Topology - Installation and configuration are difficult. - The cost of cables is high as bulk wiring is required, hence suitable for less number of devices. - The cost of maintenance is high. - A common example of mesh topology is the internet backbone, where various internet service providers are connected to each other via dedicated channels. This topology is also used in military communication systems and aircraft navigation systems. Star Topology In Star Topology, all the devices are connected to a single hub through a cable. This hub is the central node and all other nodes are connected to the central node. The hub can be passive in nature i.e., not an intelligent hub such as broadcasting devices, at the same time the hub can be intelligent known as an active hub. Active hubs have repeaters in them. Coaxial cables or RJ-45 cables are used to connect the computers. In Star Topology, many popular Ethernet LAN protocols are used as CD(Collision Detection), CSMA (Carrier Sense Multiple Access), etc. Star Topology Star Topology Figure 2: A star topology having four systems connected to a single point of connection i.e. hub. Advantages of Star Topology - If N devices are connected to each other in a star topology, then the number of cables required to connect them is N. So, it is easy to set up. - Each device requires only 1 port i.e. to connect to the hub, therefore the total number of ports required is N. - It is Robust. If one link fails only that link will affect and not other than that. - Easy to fault identification and fault isolation. - Star topology is cost-effective as it uses inexpensive coaxial cable. Disadvantages of Star Topology - If the concentrator (hub) on which the whole topology relies fails, the whole system will crash down. - The cost of installation is high. - Performance is based on the single concentrator i.e. hub. - A common example of star topology is a local area network (LAN) in an office where all computers are connected to a central hub. This topology is also used in wireless networks where all devices are connected to a wireless access point. For more, refer to the Advantages and Disadvantages of Star Topology. Bus Topology Bus Topology is a network type in which every computer and network device is connected to a single cable. It is bi-directional. It is a multi-point connection and a non-robust topology because if the backbone fails the topology crashes. In Bus Topology, various MAC (Media Access Control) protocols are followed by LAN ethernet connections like TDMA, Pure Aloha, CDMA, Slotted Aloha, etc. Bus Topology Bus Topology Figure 3: A bus topology with shared backbone cable. The nodes are connected to the channel via drop lines. Advantages of Bus Topology - If N devices are connected to each other in a bus topology, then the number of cables required to connect them is 1, known as backbone cable, and N drop lines are required. - Coaxial or twisted pair cables are mainly used in bus-based networks that support up to 10 Mbps. - The cost of the cable is less compared to other topologies, but it is used to build small networks. - Bus topology is familiar technology as installation and troubleshooting techniques are well known. - CSMA is the most common method for this type of topology. Disadvantages of Bus Topology - A bus topology is quite simpler, but still, it requires a lot of cabling. - If the common cable fails, then the whole system will crash down. - If the network traffic is heavy, it increases collisions in the network. To avoid this, various protocols are used in the MAC layer known as Pure Aloha, Slotted Aloha, CSMA/CD, etc. - Adding new devices to the network would slow down networks. - Security is very low. - A common example of bus topology is the Ethernet LAN, where all devices are connected to a single coaxial cable or twisted pair cable. This topology is also used in cable television networks. Ring Topology In a Ring Topology, it forms a ring connecting devices with exactly two neighboring devices. A number of repeaters are used for Ring topology with a large number of nodes, because if someone wants to send some data to the last node in the ring topology with 100 nodes, then the data will have to pass through 99 nodes to reach the 100th node. Hence to prevent data loss repeaters are used in the network. The data flows in one direction, i.e. it is unidirectional, but it can be made bidirectional by having 2 connections between each Network Node, it is called Dual Ring Topology. In-Ring Topology, the Token Ring Passing protocol is used by the workstations to transmit the data. Ring Topology Ring Topology Figure 4: A ring topology comprises 4 stations connected with each forming a ring. The most common access method of ring topology is token passing. Token passing: It is a network access method in which a token is passed from one node to another node. Token: It is a frame that circulates around the network. Operations of Ring Topology One station is known as a monitor station which takes all the responsibility for performing the operations. To transmit the data, the station has to hold the token. After the transmission is done, the token is to be released for other stations to use. When no station is transmitting the data, then the token will circulate in the ring. There are two types of token release techniques: Early token release releases the token just after transmitting the data and Delayed token release releases the token after the acknowledgment is received from the receiver. - Advantages of Ring Topology - The data transmission is high-speed. - The possibility of collision is minimum in this type of topology. - Cheap to install and expand. - It is less costly than a star topology. - Disadvantages of Ring Topology - The failure of a single node in the network can cause the entire network to fail. - Troubleshooting is difficult in this topology. - The addition of stations in between or the removal of stations can disturb the whole topology. - Less secure. - Types of area networks – LAN, MAN and WAN The Network allows computers to connect and communicate with different computers via any medium. LAN, MAN, and WAN are the three major types of networks designed to operate over the area they cover. There are some similarities and dissimilarities between them. One of the major differences is the geographical area they cover, i.e. LAN covers the smallest area, MAN covers an area larger than LAN and WAN comprises the largest of all. There are other types of Computer Networks also, like : PAN (Personal Area Network) SAN (Storage Area Network) EPN (Enterprise Private Network) VPN (Virtual Private Network Personal Area Network (PAN)- PAN is a personal area network having an interconnection of personal technology devices to communicate over a short distance. It covers only less than 10 meters or 33 feet of area. PAN has fewer users as compared to other networks such as LAN, WAN, etc. PAN typically uses some form of wireless technology. PAN involves the transmission of data between information devices such as smartphones, personal computers, tablet computers, etc. Advantages: - Allows for easy communication between personal devices in close proximity. - Can be set up easily and quickly. - Uses wireless technology, which eliminates the need for wires and cables. - PANs are designed to be energy efficient, which means that devices can communicate with each other without draining their batteries quickly. - PANs are typically secured using encryption and authentication protocols, which helps to prevent unauthorized access to data and resources. Disadvantages: - Limited coverage area. - May not be suitable for large-scale data transfer or communication.PANs typically have limited bandwidth, which means that they may not be able to handle large amounts of data or high-speed communication. - May experience interference from other wireless devices. Local Area Network (LAN) – LAN or Local Area Network connects network devices in such a way that personal computers and workstations can share data, tools, and programs. The group of computers and devices are connected together by a switch, or stack of switches, using a private addressing scheme as defined by the TCP/IP protocol. Private addresses are unique in relation to other computers on the local network. Routers are found at the boundary of a LAN, connecting them to the larger WAN. Data transmits at a very fast rate as the number of computers linked is limited. By definition, the connections must be high-speed and relatively inexpensive hardware (Such as hubs, network adapters, and Ethernet cables). LANs cover a smaller geographical area (Size is limited to a few kilometres) and are privately owned. One can use it for an office building, home, hospital, school, etc. LAN is easy to design and maintain. A Communication medium used for LAN has twisted-pair cables and coaxial cables. It covers a short distance, and so the error and noise are minimized. Early LANs had data rates in the 4 to 16 Mbps range. Today, speeds are normally 100 or 1000 Mbps. Propagation delay is very short in a LAN. The smallest LAN may only use two computers, while larger LANs can accommodate thousands of computers. LAN has a range up to 2km. A LAN typically relies mostly on wired connections for increased speed and security, but wireless connections can also be part of a LAN. The fault tolerance of a LAN is more and there is less congestion in this network. For example A bunch of students playing Counter-Strike in the same room (without internet). Advantages: - Provides fast data transfer rates and high-speed communication. - Easy to set up and manage. - Can be used to share peripheral devices such as printers and scanners. - Provides increased security and fault tolerance compared to WANs. Disadvantages: - Limited geographical coverage. - Limited scalability and may require significant infrastructure upgrades to accommodate growth. - May experience congestion and network performance issues with increased usage. Metropolitan Area Network (MAN) – MAN or Metropolitan area Network covers a larger area than that covered by a LAN and a smaller area as compared to WAN. MAN has a range of 5-50km. It connects two or more computers that are apart but reside in the same or different cities. It covers a large geographical area and may serve as an ISP (Internet Service Provider). MAN is designed for customers who need high-speed connectivity. Speeds of MAN range in terms of Mbps. It’s hard to design and maintain a Metropolitan Area Network. The fault tolerance of a MAN is less and also there is more congestion in the network. It is costly and may or may not be owned by a single organization. The data transfer rate and the propagation delay of MAN are moderate. Devices used for transmission of data through MAN are Modem and Wire/Cable. Examples of a MAN are part of the telephone company network that can provide a high-speed DSL line to the customer or the cable TV network in a city. Advantages: - Provides high-speed connectivity over a larger geographical area than LAN. - Can be used as an ISP for multiple customers. - Offers higher data transfer rates than WAN in some cases. Disadvantages: - Can be expensive to set up and maintain. - May experience congestion and network performance issues with increased usage. - May have limited fault tolerance and security compared to LANs. Wide Area Network (WAN) – WAN or Wide Area Network is a computer network that extends over a large geographical area, although it might be confined within the bounds of a state or country. WAN has a range of above 50 km. A WAN could be a connection of LAN connecting to other LANs via telephone lines and radio waves and may be limited to an enterprise (a corporation or an organization) or accessible to the public. The technology is high-speed and relatively expensive. There are two types of WAN: Switched WAN and Point-to-Point WAN. WAN is difficult to design and maintain. Similar to a MAN, the fault tolerance of a WAN is less and there is more congestion in the network. A Communication medium used for WAN is PSTN(Public Switched Telephone Network) or Satellite Link. Due to long-distance transmission, the noise and error tend to be more in WAN. WAN’s data rate is slow about a 10th LAN’s speed since it involves increased distance and increased number of servers and terminals etc. The speed of WAN ranges from a few kilobits per second (Kbps) to megabits per second (Mbps). Propagation delay is one of the biggest problems faced here. Devices used for the transmission of data through WAN are Optic wires, Microwaves, and Satellites. An example of a Switched WAN is the asynchronous transfer mode (ATM) network and Point-to-Point WAN is a dial-up line that connects a home computer to the Internet. Advantages: - Covers large geographical areas and can connect remote locations. - Provides connectivity to the internet. - Offers remote access to resources and applications. - Can be used to support multiple users and applications simultaneously. Disadvantages: - Can be expensive to set up and maintain. - Offers slower data transfer rates than LAN or MAN. - May experience higher latency and longer propagation delays due to longer distances and multiple network hops. - May have lower fault tolerance and security compared to LANs. Difference between Connection-oriented and Connection-less Services Both Connection-oriented service and Connection-less service are used for the connection establishment between two or more two devices. These types of services are offered by the network layer. Connection-oriented service is related to the telephone system. It includes connection establishment and connection termination. In a connection-oriented service, the Handshake method is used to establish the connection between sender and receiver. Connection-less service is related to the postal system. It does not include any connection establishment and connection termination. Connection-less Service does not give a guarantee of reliability. In this, Packets do not follow the same path to reach their destination. Difference between Connection-oriented and Connection-less Services: s.no Connection-oriented Service Connection-less Service 1 -Connection-oriented service is -Connection-less service is related to the related to the telephone system. postal system. 2 -Connection-oriented service is -Connection-less Service is preferred by preferred by long and steady bursty communication. communication. 3 -Connection-oriented Service is -Connection-less Service is not compulsory. necessary. 4 -Connection-oriented Service is -Connection-less Service is not feasible. feasible. 5 -In connection-oriented Service, -In connection-less Service, Congestion is Congestion is not possible. possible. 6 -Connection-oriented Service gives -Connection-less Service does not give a the guarantee of reliability. guarantee of reliability. 7 -In connection-oriented Service, -In connection-less Service, Packets do not Packets follow the same route. follow the same route. 8 -Connection-oriented services require -Connection-less Service requires a bandwidth a bandwidth of a high range. of low range. 9 -Ex: TCP (Transmission Control -Ex: UDP (User Datagram Protocol) Protocol) 10 -Connection-oriented requires -Connection-less Service does not require authentication. authentication.
