Describe in detail the function of the following network devices:

Networking Devices Describe in detail the function of the following network devices: 1. NIC In computer networking, a NIC (Network Interface Controller or Card) provides the hardware interface between a computer and a network. A NIC technically is network adapter hardware in the form factor of an add-in card such as a PCI or PCMCIA card. Some NIC cards work with wired connections while others are wireless. Most NICs support either wired Ethernet or WiFi wireless standards. Ethernet NICs plug into the system bus of the PC and include jacks for network cables, while WiFi NICs contain built-in transmitters / receivers (transceivers). 2. Hub Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets. A passive hub serves simply as a conduit for the data, enabling it to go from one device (or segment) to another. So-called intelligent hubs include additional features that enables an administrator to monitor the traffic passing through the hub and to configure each port in the hub. Intelligent hubs are also called manageable hubs. 3. Gateway A gateway is a node that allows you to gain entrance into a network and vice versa. On the Internet the node which is the stopping point can be a gateway or a host node. A computer that controls the traffic your network or your ISP (Internet Service Provider) receives is a node. In most homes a gateway is the device provided by the Internet Service Provider that connects users to the internet. 4. Router A device that forwards data packets along networks. A router is connected to at least two networks, commonly two LANs or WANs or a LAN and its ISP��s network. Routers are located at gateways, the places where two or more networks connect. Routers use headers and forwarding tables to determine the best path for forwarding the packets, and they use protocols such as ICMP to communicate with each other and configure the best route between any two hosts. 5. Switch A network switch is a small hardware device that joins multiple computers together within one local area network (LAN). Technically, network switches operate at layer two (Data Link Layer) of the OSI model. Network switches appear nearly identical to network hubs, but a switch generally contains more intelligence (and a slightly higher price tag) than a hub. Unlike hubs, network switches are capable of inspecting data packets as they are received, determining the source and destination device of each packet, and forwarding them appropriately. 6. Bridge A bridge is a device that separates two or more network segments within one logical network (e.g. a single IP-subnet). A bridge is usually placed between two separate groups of computers that talk with each other, but not that much with the computers in the other group. A good example of this is to consider a cluster of Macintoshes and a cluster of Unix machines. Both of these groups of machines tend to be quite chatty amongst themselves, and the traffic they produce on the network causes collisions for the other machines who are trying to speak to one another. The job of the bridge is to examine the destination of the data packets one at a time and decide whether or not to pass the packets to the other side of the Ethernet segment. The result is a faster, quieter network with less collisions. The bridging code decides whether to bridge data or to drop it not by looking at the protocol type (IP, IPX, NetBEUI), but by looking at the MAC-address unique to each NIC. 7. Server A network server is a computer designed to process requests and deliver data to other (client) computers over a local network or the Internet. Network servers typically are configured with additional processing, memory and storage capacity to handle the load of servicing clients. Common types of network servers include: Web servers: 1.proxy servers 2.FTP servers 3.online game servers 8. Workstation A type of computer used for engineering applications (CAD/CAM), desktop publishing, software development, and other types of applications that require a moderate amount of computing power and relatively high quality graphics capabilities. Workstations generally come with a large, high-resolution graphics screen, at least 64 MB (megabytes) of RAM, built-in network support, and a graphical user interface 9. Thin Client A thin client refers to either a software program or to an actual computer that relies heavily on another computer to do most of its work. It operates as part of a network, with the client software or computer acting as an interface and the network server computer doing all the real work, like saving files, processing data, and controlling certain functions of the clients, like whether they can download things or not. This type of setup is commonly used in places with lots of people simultaneously using computers, like businesses or schools. 10. Thick Client A thick client is a computer that does not require a connection to a server system in order to run (unlike a thin client), although they can benefit from being connected to a network and a server. Thick clients are often found in the business environment, where servers are used to provide some data and application support, but the thick client (office computer) is largely independent. Thick clients have their own operating system and software applications and can be used offline (not connected to a network or server).

A thick client is a computer that does not require a connection to a server system in order to run (unlike a thin client), although they can benefit from being connected to a network and a server.

Thick clients are often found in the business environment, where servers are used to provide some data and application support, but the thick client (office computer) is largely independent. Thick clients have their own operating system and software applications and can be used offline (not connected to a network or server).

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