Basic of Networking: unicast, multicast or component require for LAN connection

 

Network – A network is a connection of devices through internet that allows the information to be exchanged between two devices or computers.

Node - A node or device is anything that is connected to the network. It can be an end devices like printer, scanner etc.

Segment - A segment is any portion of a network which is separated by a switch, bridge or router, from other parts of the network.

Backbone - The backbone is the main cabling of a network that all of the segments connect to. The backbone is capable of carrying more information than the individual segments. For example, segment may have a capability of transfer rate of 10 Mbps, while the backbone may operate at 100 Mbps.

Topology – It is the way of connecting network or devices. Some of the topologies are star, mesh, node and bus topology.

Local Area Network (LAN) - A LAN is a network of computers that are in the same general physical location, usually within a building or a campus. If the computers are far apart (such as across town or in different cities), then a Wide Area Network (WAN) is typically used.

Difference between LAN and MAN

A wide area network (WAN) is a series of LANs linked together to form a network in an extended area. WANs are typically operated by telecommunications companies or businesses that need a network comprising multiple remote locations. The internet itself is a WAN.

Fibre optical cable is the preferred transmission medium for WANs because fibre optic can transmit large amounts of data at high speeds. As is the case with the internet, a WAN can also include metropolitan area networks (MANs).

 

Network Interface Card (NIC) or Network adapter or LAN adapter - It is a hardware component without which a computer cannot be connected over a network. It is a circuit board installed in a computer that provides a dedicated network connection to the computer.

Media Access Control (MAC) address - This is the physical address of any device such as the NIC in a computer. The MAC address is made up of two equal parts is 6 bytes long where the first 3 bytes identify the company that made the NIC and the second 3 bytes are the serial number of the NIC.

Unicast - A unicast is a transmission from one node to another node.

Multicast - In a multicast, a node sends a packet addressed to a multiple group address. It is used to transmit message to multiple nodes at a same time.

Broadcast - In a broadcast, a node sends out a packet that is intended for transmission to all other nodes on the network. It is used to broadcast any important updates to all the other nodes.

In the most basic type of networking, nodes are simply connected together using hubs or switch. As a demand of the network grows, there are some potential problems arise with the configuration.

Scalability - In a hub network, due to the limited bandwidth it is difficult to accommodate significant large number of devices without sacrificing the performance of the network. In today world, applications required more bandwidth than earlier requirements. Hence, sometimes we need to re-designed whole network again for addressing the scalability factors.

Latency - This is the amount of time taken by a packet to reach to its destination node.  This is because each node in a network has to wait for an opportunity to transmit in order to avoid collisions which significantly increase the latency of the device. Or, if someone is transmitting a large file across the network, then all of the other nodes have to wait for an opportunity to send their own packets.

Network failure - In a typical network, one device on a hub can cause problems for other devices attached to the hub due to incorrect speed settings (100 Mbps on a 10-Mbps hub) or excessive broadcasts. Switches can be configured to limit broadcast levels.

Collisions -Ethernet uses a process called CSMA/CD (Carrier Sense Multiple Access with Collision Detection) to communicate across the network. Under CSMA/CD, a node will not send out a packet unless the network is clear of traffic. If two nodes send out packets at the same time, a collision occurs and the packets are lost. Then both nodes wait a random amount of time and retransmit the packets. Any part of the network where there is a possibility that packets from two or more nodes will interfere with each other is considered to be part of the same collision domain. A network with a large number of nodes on the same segment will often have a lot of collisions and therefore a large collision domain.

While hubs provide an easy way to scale up and shorten the distance that the packets must travel to get from one node to another, they do not break up the actual network into discrete segments. That is where switches come in.

 

Necessary components for a LAN Connection:

To build a LAN or WLAN, you need the following:

Ø  Computers with Network Interface Cards (NIC): Most modern computers, laptops and tablets come with a network interface card (NIC) for Ethernet and Wi-Fi. This allows the machine to connect to a network. The NIC should come with driver software that the operating system automatically configures and updates.

Ø  Cables: Unshielded Twisted Pair (UTP) cables are the standard (Cat-X cables, where X is a number that indicates the maximum speed, a cable will fetch). Fibre optical cables provides higher speeds as compare to other type of cable wire.

Ø  Switches and Hubs: You will require a switch or hubs to connect the cables to network. A hub divides up and shares data packet transmission with all the computers on a LAN, while switches dedicate packet transmission to a single computer, which reduces network traffic.

Ø  Routers: Network routers allow you to connect to other LANs (if need be), and they assign IP addresses to your devices. A wireless router will allow computers with Wi-Fi NICs to connect with each other and with the internet.

Ø  Modem: If you’re going to connect a LAN to other LANs or to the internet to form a WAN, a modem facilitates signal conversion and reversion.

Ø  Software: Network software should come with your operating system of choice, but you’ll also need to download security software.

Ø  Dynamic Host Configuration Protocol (DHCP) Server: You will need a computer with large RAM and hard drive space to act as your DHCP server.

Setting up a LAN, WLAN or WAN can be very complex task depending on the size of the network you want to establish.

         <<<<<<<Network Cables and its types>>>>>>>>>