Understanding Networking Devices for beginner

Local area networks (LAN's) are most commonly used by the organizations. The organizations need to connect multiple LAN's together to extend networks. The networking devices are also called as Inter-networking devices which act as an intermediate agent for transmission of data in the network. The networking devices include hubs, switches, routers and gateways. These devices interconnect the systems linked into large, spread out groups of LAN's. The networking devices manage networks by dividing a single network into multiple sub-networks. This reduces the number of nodes on a network and so network traffic is also reduced. The networking devices also provide security by restricting Individuals to specified resources and increases system reliability.

Network Interface Card

In a network, to send the data the node requires the destination address. In a network, each node should have its own address to send and receive their data.’ This address is known as physical or MAC (Media Access Control) address. It is provided by a device known as Network Interface Card (NIC) and it operates at layer 2 of the OSI model. A Network Interface Card (NIC) is a hardware device that is used to ‘connect a node into a network. NIC is fitted into the expansion slot inside the computer. It serves as a link for sending and receiving data on the network. It can support a transfer rate of 10, 100 or 1000 Mbps. The user can select an NIC depending on the type of network, protocol and media. 

The speed and performance of the network also depends on the network card. Every node on the network should have a network card with a unique Media Access Control (MAC) address. The MAC address is the address that is assigned by IEEE to uniquely identifying a network card. This address is stored on the Programmable Read-Only. NIC showing in figure 1.0

Types of NIC (Network Interface Card)

 Ethernet cards are of two types:

• Wired

• Wireless

To connect a wired Ethernet card to the switch or hub, Ethernet cables are used. MAC address are used by the switches and hubs to transmit data between different nodes

Wireless Ethernet cards have a small antenna which uses radio waves to communicate with the central wireless hub or switch known as Access Point

Hub

A hub is a Repeater with multiple ports simply receives the data from one port and sends the data to all the ports. Hub allows multiple devices to be connected from a Single network segment. Hub operates. at the physical layer (Layer 1). It is the Simplest networking device hence has low cost. Hub can connect different media types. such as twisted pair and coaxial cable. Hub Showing in bellow image

Switch

Now a day’s switches are mostly used in LAN due to their superior throughput performance, higher port density, lower per-port cost and greater flexibility. The cost of switch depends on the number of ports. As the number of ports increases, cost increases. 
Switch is available in 5, 8, 10, 16, 24, 28, 48, and 52-port. s

Routers

Router is an Intelligent Network layer (layer 3) device. It connects two or more network segments which may be near or very far and having different types of cabling. Hence it can work in LAN and WAN environments. Router has LAN ports which are used to connect to your LAN or computer and WAN ports which are generally used to connect to some other connection that links to regular phone line, a more advanced telephone connection like ISDN, ADSL, may be a cable modem.

Router showing in figure 1.0 

                       

Gateways

Gateway is a networking device which acts as an entrance (or a gate) for another network. In enterprises, the gateway is a device that routes the traffic from an internal network to the outside network. The gateway node often acts as a proxy server or a firewall or a router. A router uses headers and forwarding tables to determine where packets are sent. A gateway will not know all the routes to reach every address on the internet, but it will have the addresses of other gateways to which it can handover the traffic. A default gateway is the one that meets the following criteria:

• It is on the same subnet as your computer.
• It is the gateway that your computer depends upon when it does not know through which route to send the traffic towards destination.

Gateway interconnects different networks and provides a translation service from one protocol stack to another for network communication. The basic function of a gateway is to translate data from one format to another. It does not convert the actual data. Gateway works at all levels of the OSI model.

getway device showing in figure 1.0 

Access Point/Wireless Router

In local area network wireless routers are mostly used. this is a networking device which is used for connecting other devices without any wire media. wireless router have an antenna to broadcast signals. it is also called Wi-fi router, we  can share our internet connection without any wired media. 

So that are the mostly used networking devices, In old computer there was no LAN port on motherboard so we needed Network Interface card for networking this was installed on motherboard PCI slot, and we can connect LAN cable through it. now a days NIC is inbuilt with motherboard and we Need extrrnal NIC when inbuilt is not working or when need more then one NIC on single computer hub is a old networking device and  now a days hub is not using in LAN/Networking.

Networking devices showing in figure 1.0

Figure 1.0

Related Topic

Types of networking cables