2. SYLLABUS
◦ LAN
◦ WAN
◦ Wireless Network
◦ Introduction to networking
◦ Importance of networking
◦ Communication devices such as Modem
◦ Features of Networking
3. 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.
4. 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.
◦ 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 or Satellite Link.
◦ Due to long-distance transmission, the noise and error tend to be more in WAN.
5. Wireless Network
◦ Computer networks that are not connected by cables are called wireless networks.
◦ They generally use radio waves for communication between the network nodes.
◦ They allow devices to be connected to the network while roaming around within the network coverage.
◦ Types of Wireless Networks
◦ Wireless LANs − Connects two or more network devices using wireless distribution techniques.
◦ Wireless MANs − Connects two or more wireless LANs spreading over a metropolitan area.
◦ Wireless WANs − Connects large areas comprising LANs, MANs and personal networks.
◦ Examples of wireless networks
◦ Mobile phone networks
◦ Wireless sensor networks
◦ Satellite communication networks
6. Introduction to networking
◦ Computer Network is a group of computers connected with each other through wires, optical fibres or optical links so that
various devices can interact with each other through a network.
◦ The aim of the computer network is the sharing of resources among various devices.
◦ In the case of computer network technology, there are several types of networks that vary from simple to complex level.
7. Importance of networking
◦ In today’s world computer has become an integral part of the business sector for professional activities not only for
professional activities but for personal activities also.
◦ As technologies have evolved networking came into the picture and slowly from initial wired network technology we moved to
this wireless network technology.
◦ Now if we will think then we can know that networking impacts everything.
◦ Computer Network is an interconnection between computers or we can say computer network is group of computers linked to
each other which enables one computer to communicate with another computer.
◦ It acts as basis of communication in Information Technology (IT).
◦ It is system of connected computing devices and shares information and resources between them.
◦ The devices in network are connected by communication links (wired/wireless) and share data by Data Communication System.
8. Communication devices such as Modem
◦ Any hardware that can send and receive data, instructions, and information is referred to as a communications device.
◦ A modem is one kind of communication tool that joins a channel to a sending or receiving device, like a computer.
◦ Data is processed by computers as digital signals.
◦ Depending on the communications channel, data, instructions, and information can move along it in analogue or digital form.
◦ An electrical wave that is continuous makes up an analogue signal.
◦ Individual electrical pulses that represent bits and bytes are what make up a digital signal.
9. CONT……
◦ The modem transmits digital signals between the computer and the communications channel for channels that employ digital
signals (such as cable television lines).
◦ However, the modem must first convert between analogue and digital signals if the communication channel uses analogue
signals (such as some telephone lines).
10. Communication device examples
◦ 1. Bluetooth device: The Bluetooth specification outlines how devices can connect with one another in the computing and
telecommunications industries.
◦ Computers, a keyboard and mouse, personal digital assistants, and smartphones are examples of devices that use Bluetooth.
◦ 2. Infrared device: It is a technique for data transport without the usage of cables. A TV remote is a typical illustration of an
infrared (Ir) gadget. But infrared is also employed by computers and gadgets like cordless keyboards, mice, and touch screens.
◦ 3. Smartphone: A smartphone is a cell phone that offers more features than just texting and calling. Smartphones have the
ability to use software just like a PC and browse the Internet. Smartphones have touch screens that enable user interaction.
Numerous apps for smartphones, including games and apps for personal and professional use, are available. The Apple iPhone,
one of the most well-known smartphones on the market today.
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◦ 4. Wi-Fi device: Wi-Fi is a wireless network that connects to a network wirelessly by using one of the IEEE 802.11 wireless
standards. A wireless access point or router is used in a home wireless network to broadcast a signal while encrypting it with
WAP or WEP to send and receive data from wireless devices connected to the network.
◦ 5. Network interface card: The NIC, which stands for network interface card, is also known as an Ethernet card and a network
adapter. An Ethernet cable with an RJ-45 connector is used to connect a computer to a network (such as your home network or
the Internet) using a NIC.
12. Features of Networking
◦ A list Of Computer network features is given below.
◦ Communication speed
◦ File sharing
◦ Back up and Roll back is easy
◦ Software and Hardware sharing
◦ Security
◦ Scalability
◦ Reliability
13. CONT…..
◦ Communication speed
◦ Network provides us to communicate over the network in a fast and efficient manner. For example, we can do video
conferencing, email messaging, etc. over the internet. Therefore, the computer network is a great way to share our knowledge
and ideas.
◦ File sharing
◦ File sharing is one of the major advantage of the computer network. Computer network provides us to share the files with each
other.
◦ Back up and Roll back is easy
◦ Since the files are stored in the main server which is centrally located. Therefore, it is easy to take the back up from the main
server.
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◦ Software and Hardware sharing
◦ We can install the applications on the main server, therefore, the user can access the applications centrally. So, we do not need to install
the software on every machine. Similarly, hardware can also be shared.
◦ Security
◦ Network allows the security by ensuring that the user has the right to access the certain files and applications.
◦ Scalability
◦ Scalability means that we can add the new components on the network. Network must be scalable so that we can extend the network
by adding new devices. But, it decreases the speed of the connection and data of the transmission speed also decreases, this increases
the chances of error occurring. This problem can be overcome by using the routing or switching devices.
◦ Reliability
◦ Computer network can use the alternative source for the data communication in case of any hardware failure.
