Computer networks, by Ana Bugallo and Julia Martínez
Julia Martínez Tomé & Ana Bugallo.3º ESO- A.
1. What’s a computer network? 2. Categories of computer networks:2.1. Local area networks or LANs.2.2. Metropolitan area networks or MANs.2.3. Wide area networks or WANs. 3. Fundamental elements 4. Internet access
A computer network is a set of computersconnected to each other so they can shareresources and exchange information.
We can divide the computer networks in threetypes:1. Local area networks or LANs.2. Metropolitan area networks or MANs, madeup of several LANS.3. Wide area networks or WANs, covering acountry or continent.
The LANs arecomputernetworks thatinterconnectcomputers in alimited area such as ahome, school, computer laboratory oroffice building, usingnetwork media.
A MAN is a computer network that usually spans a cityor a large campus. A MAN usually interconnects anumber of LANs using a high-capacity backbonetechnology, such as fiber-optical links, and providesup-link services to WAN and the Internet.
A WAN is a network that covers a broadarea (i.e. any telecommunicationsnetwork that links acrossmetropolitan, regional or nationalboundaries) using private orpublic network transports. They are also call Wireless LANs.
They use electromagnetic waves to transmitdata. Networks with a combination of wired andwireless devices use wireless access points orWAP that can transmit data through wires orelectromagnetic waves.
An adaptor (orNetwork Card network card) tosend and receiveinformationto and fromother computers.
The hub distributes all Hubof the information itreceives among theother computers in thenetwork.
A cable similar to a RJ45 connectortelephone wire withan RJ45 connector atthe end whichlets theinformation passthrough it.
We can use coaxial and opticalfiber cables for this function.Optical fiber cable Coaxial cable
We can connect to the Internet in twodifferent ways.What are they?
Using Internet ConnectionSharing (ICS), in which onecomputer is switchedon all the time so that allthe communication can gothrough it.
Using a router, adevice which detectsdata and directs it toand from the Internet.
But network sharing has got onedisadvantage.What could it be?
In order for theother users Us to be able to access theInternet,the computer withall the sharedelements must beswitched on at alltimes.