What is Networking ?
A computer network comprises two or more computers that are connected—either by wired or wireless with the purpose of transmitting, exchanging, or sharing data and resources. You build a computer network using hardware (e.g., routers, switches, access points, and cables) and software (e.g., operating systems or business applications). Geographic location often defines a computer network. For example, a LAN (local area network) connects computers in a defined physical space, like an office building, whereas a WAN (wide area network) can connect computers across continents. The internet is the largest example of a WAN, connecting billions of computers worldwide. You can further define a computer network by the protocols it uses to communicate, the physical arrangement of its components, how it controls traffic, and its purpose. Live streaming, and Social network all exist Because Of Computer Networks.
Types Of Computer Networks
- LAN (Local Area Network) :– A LAN connects computers over a relatively short distance, allowing them to share data, files, and resources. For example, a LAN may connect all the computers in an office building, school, or hospital. Typically, LANs are privately owned and managed.
- WLAN (Wireless Local Area Network) :– A WLAN is just like a LAN but connections between devices on the network are made wirelessly.
- WAN (Wide Area Network) :– As the name implies, a WAN connects computers over a wide area, such as from region to region or even continent to continent. The internet is the largest WAN, connecting billions of computers worldwide. You will typically see collective or distributed ownership models for WAN management.
- MAN (Metropolitan Area Network) :– MANs are typically larger than LANs but smaller than WANs. Cities and government entities typically own and manage MANs.
- PAN (Personal Area Network) :– A PAN serves one person. For example, if you have an iPhone and a Mac, it’s very likely you’ve set up a PAN that shares and syncs content— text messages, emails, photos, and more—across both devices.
- SAN ( Storage Area Network ) :– A SAN is a specialized network that provides access to block level storage—shared network or cloud storage that, to the user, looks and works like a storage drive that’s physically attached to a computer.
- CAN (Campus Area Network) :– A CAN is also known as a corporate area network. A CAN is larger than a LAN but smaller than a WAN. CANs serve sites such as colleges, universities, and business campuses.
- VPN (Virtual Private Network) :– A VPN is a secure, point–to–point connection between two network end points (see ‘Nodes’ below). A VPN establishes an encrypted channel that keeps a user’s identity and access credentials, as well as any data transferred, inaccessible to hackers.
Important Terms / Concepts
- IP Address :– An IP address is a unique number assigned to every device connected to a network that uses the Internet Protocol for communication. Each IP address identifies the device’s host network and the location of the device on the host network. When one device sends data to another, the data includes a ‘header’ that includes the IP address of the sending device and the IP address of the destination device.
- Nodes :– A node is a connection point inside a network that can receive, send, create, or store data. Each node requires you to provide some form of identification to receive access, like an IP address. A few examples of nodes include computers, printers, modems, bridges, and switches. A node is essentially any network device that can recognize, process, and transmit information to any other network node.
- Ports :– A port identifies a specific connection between network devices. Each port is identified by a number. If you think of an IP address as comparable to the address of a hotel,
then ports are the suites or room numbers within that hotel. Computers use port numbers to determine which application, service, or process should receive specific messages.
- Computer Network :– An interconnection of multiple devices, also known as hosts, that are connected using multiple paths for the purpose of sending/receiving data or media. Computer networks can also include multiple devices/mediums which help in the communication between two different devices; these are known as Network devices and include things such as routers, switches, hubs, and bridges.
- Network Topology :– The layout arrangement of the different devices in a network. Common examples include: Bus, Star, Mesh, Ring, and Daisy chain.
- OSI :– OSI stands for Open Systems Interconnection. It is a reference model that specifies standards for communications protocols and also the functionalities of each layer.
- Portocol :– A protocol is the set of rules or algorithms which define the way how two entities can communicate across the network and there exists different protocol defined at each layer of the OSI model. Few of such protocols are TCP, IP, UDP, ARP, DHCP, FTP and so on.
- IP Address (Internet Protocol address) :– Also known as the Logical Address, the IP Address is the network address of the system across the network. To identify each device in the world–wide–web, the Internet Assigned Numbers Authority (IANA) assigns an IPV4 (Version 4) address as a unique identifier to each device on the Internet. The length of an IPv4 address is 32–bits, hence, we have 232 IP addresses available. The length of an IPv6 address is 128–bits.
- MAC Address (Media Access Control address) :– Also known as physical address, the MAC Address is the unique identifier of each host and is associated with its NIC (Network Interface Card). A MAC address is assigned to the NIC at the time of manufacturing. The length of the MAC address is : 12–nibble/ 6 bytes/ 48 bits .