Cable Modem: A cable modem can utilise the cable network used by subscription-based (pay TV) television broadcasters – for example FOXTEL™ – to connect a computer to the internet. A cable splitter is required to separate the broadband internet data from digital TV transmission data.
Dial-Up Modem: A networking component that connects a computer to an internet service provider, or another computer. The dial-up modem converts the digital signals (data) from a computer into an analogue electrical signal that can be transmitted across standard telephone lines. The modem also receives the analogue signal from the telephone line and converts it to a digital signal that a computer can process.
DSL Router: When telephone exchanges are upgraded with digital switches, standard telephone lines can transmit digital data. There is no need for the analogue to digital conversion provided by dial-up modems. A user connected to the internet uses a DSL (Digital Subscriber Line) router to manage communications between their internet service provider and their own computer. This allows data transfer at broadband internet speeds. An ADSL (Asynchronous Digital Subscriber Line) router is the most common device used to connect to the internet by home and small business users. An ADSL router allows for a faster download speed and a lesser upload speed.
HUB:
Hubs have been replaced in the marketplace by switches. The hub is an early networking product. A hub connects computers in a local area network. The connection interfaces are called ports and use the same interface connector as the network interface card – the RJ-45. . The destination computer recognises the destination address information in the data packet as its own and accepts the data. Hubs make it possible to easily add computers to a network, and they can be cascaded (joined to other hubs), providing flexibility in cable layout. Although hubs are virtually obsolete, an understanding of their function will help you understand how more recent products work.
Network Interface Card: For computers without networking capabilities provided by the motherboard, an ethernet network interface card, also called an ethernet adapter, is required to connect to a network.
Node: A node is a component of a network that has data processing ability. Each node has a Media Access Control (MAC) address. A MAC is a unique hardware address on a network and on the internet. Examples of nodes are: network interface cards, ADSL routers, switches, printers, networked photocopiers and computers with onboard networking capabilities.
Router: A router is a network communications device that connects two or more computer networks together. Its task is to direct packets* of data to their correct destination on each network. A router is the hardware component of a gateway used to connect two networks. A server with two network interfaces can also act as a router.
Server: Client/server networks require a server to manage network functions, data communications and data security on network drives. ADSL modems connect servers to the internet. Servers can share this connection – via a switch – with other computers on the network.
Line Filter: When the standard telephone line is converted to a digital subscriber line (DSL), the cable carries the normal telephone signals as well as the broadband internet signals from the internet service provider. For a normal telephone to function, the low frequency telephone signal must be separated from the high frequency broadband internet signal. This is done with a line filter. The line filter filters out the broadband ‘noise’ so the telephone voice data can be ‘heard’ on the telephone without interference. The line filter often sits between the telephone socket and the telephone.
Switch:
Switches can be considered to be intelligent hubs. They inspect each packet of data coming in for their destination address information and send the packet down the correct cable to the destination computer. A switch makes a direct connection between the sending computer and the receiving computer.
Wireless Access Point:
A communications device that allows the transfer of data between computers using radio transmissions. This function can be provided by the motherboard of a computer, an expansion card or by using an external device. Each computer connected to the network via the wireless access point requires a wireless interface card to complete the connection, or a similar onboard wireless capability.
A wireless access point is often used to connect computers wirelessly in an office or home network. A wireless access point is the wireless equivalent of a hub.
