Chapter 6 Flashcards
LAN
A collection of computers and peripheral devices connected together within a single site.
WAN
A collection of computers and LANs connected together over a geographically remote area, using leased infrastructure.
Topology
A description of how devices are connected together. Does not necessarily represent physical layout.
Bus
A topology where each device is connected to a main cable, referred to as the bus. Any device can transmit at any time but only one transmission can occur on the main bus at any one time.
Ring
A topology where each device is connected to the next in a loop. Uses a tokenpassingprotocol to allow transmission by one device at a time.
Star
A topology where each device has its own cable connecting it to a central device, which can be a switch or a server.
Peer-to-Peer
A method of organising devices in a network where devices are all of equal status rather than having specialised roles. Each computer can access resources on another computer, assuming access rights have been granted by the other computer.
Client-Server
A method of organising devices in a network where some computers havespecialised roles: servers. The servers provide resources and services to the other computers, known as clients. Management of the network and shared resources/files is centralised at the server.
Hub
A hardware device that provides connectivity to a LAN cable. A multiport box that has a connection to the LAN from one side and several computers on the other. Can be wireless or cabled.
Switch
A hardware device that is similar to a hub but it has built-in intelligence to direct traffic to the right place. Computers connected to a switch form a star topology LAN.
Wireless Access Point
The device to which a computer connects wirelessly. Can be a wireless hub or awireless switch.
NIC
Network Interface Card: the card that plugs into a computer to provide a connection to a LAN. Can be wireless or cabled. Holds the MAC address.
MAC Address
A unique hardware number allocated to every NIC. It is a 48-bit address, usually written in hex, e.g. 00-09-7C-F1-F7-85
Message
A communication between devices. Split into packets for sending over a networkand put back together again at the other end.
Packet
A fixed size chunk of a message created to send a message over a network. Ithas its own header containing data such as the destination address and packet number (so the message can be put back together in the right order).
Protocol
A set of rules that defi nes how devices communicate. E.g. IP, HTTP, HTTPS
Internet
A public worldwide network where computers and networks in geographicallyseparate locations are connected together using a variety of communication links.Devices communicate using Internet Protocol (IP).
Routers
The hardware devices that make up the backbone of the Internet as well as (smaller ones) providing connectivity from a LAN to the Internet. Use Internet Protocol to communicate with each other.