Hardware that enables the device to connect to the network medium, either wired or wireless
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CommunicationDevices can be networked using different hardware, such as routers, hubs, switches, gateways and bridges. They can cover local areas (LANs) or wider areas (WANs). Networks are constructed using different topologies, including ring, bus, star and mesh. All of these differences have advantages and disadvantages to users. To connect a computer or device to a
local area network (LAN), several
hardware components are required: A network interface card (NIC) provides a method of connecting to a network. A NIC offers an interface
port for a wired connection. A wireless network interface controller (WNIC) provides a radio
transceiver for connecting wirelessly. Most modern PCs come with a NIC and WNIC built in,
providing the option of either connection method. However, mobile devices such as tablets, smartphones and many embedded devices feature only a WNIC, giving only wireless connection. Transmission media carry data signals from one computer to another. Media are either wired or wireless. In modern networks, wired media use either twisted copper wiring or fibre-optic cable. Each wired
medium has particular characteristics: Wired connections are reliable and not usually subject to interference. However, they limit mobility - a wired device usually has to stay in place. Most modern wired LANs use CAT6 cabling that allows connection speeds of up to 250 megahertz (MHz). Wireless connections use radio waves to carry signals. These signals are limited in range (usually up to 50 metres) but are subject to magnetic interference. They can also be blocked by walls. However, they are ideal for mobile devices, which can connect to a network as long as they are in the range of a wireless access point (WAP). Network connection devicesA network connection device allows computers to connect to a network and transmit data. There are several types of connection device to consider:
HubsA hub is a small device that allows wired devices to connect to a network. Hubs have no knowledge of the devices connected. That means that all packets of data that arrive at the hub are transmitted to all connected computers. This affects network performance, as many unnecessary signals are transmitted across its connections. SwitchesSwitches are similar to hubs, with one important difference - a switch records which computers are connected to which ports. When a message is received, the switch forwards each packet of data to its intended recipient only. This improves network performance by cutting down on unnecessary transmissions. A hub broadcasts messages to all devices on the network. A switch sends the message to the intended recipient only. Wireless access pointsA wireless access point (WAP) uses a radio transceiver to allow wireless connections to a network. In effect, the WAP creates its own wireless network which devices connect to. The WAP then sends the wireless traffic data it receives onto the main wired network. WAPs can also be used to extend the range of a wireless network. In this case, the WAP can either receive and transmit traffic data to other WAPs or it can be connected via a cable to the main network. RoutersRouters are one of the most commonly used connection devices. They are used to send data signals across the internet. Routers work by storing the addresses of computers on the network. They then determine the most suitable route for sending data. Routers are also commonly used in homes. Home routers usually contain a hub and a WAP, enabling a small peer-to-peer network to be formed. They also contain a modem, which allows users to connect to the internet. GatewaysA gateway joins together two networks that use different protocols, for example joining a LAN to a WAN. BridgesA bridge joins together two networks that use the same protocols, for example joining a LAN to another LAN.
GCSE Subjects
What internal device does a computer use to connect to a wired or a wireless network?1. A modem or broadband modem is a hardware device that connects a computer or router to a broadband network. For example, a cable modem and DSL modem are two examples of these types of Modems. Today, a "modem" is most often used to describe a broadband modem.
What hardware does the network need in order to connect to it wirelessly?The key hardware components of a wireless computer network include adapters, routers and access points, antennas, and repeaters.
Which medium does WIFI use to send data between networks and devices?Wi-Fi uses radio waves to transmit information between your device and a router via frequencies. Two radio-wave frequencies can be used, depending on the amount of data being sent: 2.4 gigahertz and 5 gigahertz.
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