Computer Network

A computer network is a group of computer systems and other computing hardware devices that are linked together through communication channels to facilitate communication and resource-sharing among a wide range of users. Networks are commonly categorized based on their characteristics.

Types of Computer Networks:

• Depending on its size or coverage area:

-LAN (Local Area Network):It is a computer network that use interconnects computers in a limited area such as a home, school, computer laboratory, or office building using network media. 

 -PAN (Personal Area Network):A personal area network (PAN) is a computer network used for data transmission among devices such as computers, telephones and personal digital assistants. PANs can be used for communication among the personal devices themselves (intrapersonal communication), or for connecting to a higher level network and the Internet (an uplink).

PAN.

   -WAN (Wide Area Network):is a network that covers a broad area (any        telecommunications network that links across metropolitan, regional, or national boundaries) using private or public network transports.

WAN

-MAN (Metropolitan Area Network): It´s for a city.

MAN

                                                     

•   Depending on your level of access or privacy:

-Internet :It is a worldwide network of computer networks. Have    public access.

 -Intranet: It is a local network that uses Internet tools (web, mail, ftp, ...). It can be considered as a private Internet which operates within the same institution.

-Extranet:  It is a virtual private network, that is part of the Intranet of an organization extends beyond users.

• According to their functional relationship:

-P2P(Peer to Peer): All devices can act as clients or servers.

-Client-Server : The client–server model of computing is a distributed application structure that partitions tasks or workloads between the providers of a resource or service.     

• According to the typology:                                                                                                                                                                                                                                                                                                  
• According to physical medium:

-Wireless: Wireless networks are computer networks that are not connected by cables of any kind.

 -Mixed :

-Wired:A wired network is one  in wich all the components are conected with networks cables.                                                                                                    

Characteristics of computer network

The computers are comunicated through a protocol with numerical adress,it´s the IP.

An IP address is a numerical label that identifies a logical and hierarchical manner, to an interface (communication element / connection) of a device (usually a computer) within a network using (Internet Protocol) IP protocol, which corresponds at the network layer of the OSI model.

• Types of IP :

-Type A: they are the networks with a IP direction between 0.0.0.0 and 127.0.0.0.

-Type B: they are the networks  with a IP direction between 128.0.0.0 and 191.0.0.0.

-Type C: they are the networks with a IP direction between 192.0.0.0 and 223.0.0.0.