Networking Week 1

Host

A computer that provides end users with services such as computation and database access and that usually performs network control functions. Often a server running a NOS.

Router Connectivity device

A generic term for connecting devices to each other in order to transfer data from one node to another. It often refers to bridges, routers, switches and gateways. It can also encompass backbone networks.

Elements Common to Client/Server Networks- Server

A system (software or hardware) that responds to requests across a computer network to provide, or help to provide, a network service.

Elements Common to Client/Server Networks- Client

A user's computer or device. This could be a desktop, laptop, tablet, or even smart phone connected to a network. Also commonly called a Node.

NOS (network operating system)

An operating system designed to run across a network, usually on a server. Network OS are typically designed to provide access to server resources to clients.

Node

Any system or device connected to a network is called a node.

Protocol

Defines rules and conventions for communication between network devices. Protocols for computer networking all generally use packet switching techniques to send and receive messages in the form of packets.

LANs, MANs, and WANs

Keep in mind as you read the terminology the most widely used terms for networks are LANs and WANs. Other terms such as MAN and CAN are seldom used in practice.

Types of Networks

Networks can communicate over both short and long distances. Though there are infinite variations in network designs, two basic types exist in today s business and personal networks. The design of any network is dependent on the requirements of the organization, size or scale of the installation, and purpose of the network. The two main types of networks are Peer to Peer (p2p) and Client and Server.

Peer-to-Peer Networks

Peer to Peer networks are cost effective and easy to deploy, but only efficiently support a small number of computers before becoming unwieldy. Peer to peer networks are appropriate for home networks and small businesses with a small number of computers, or nodes, usually less than 10. All computers have the same role within the network and no computer controls any resources on other nodes. Maintaining security is difficult because each workstation is responsible for its own security. Using the p2p model, files and resources can be shared with all computers.

NIC (network interface card)

Pronounced "nick," this is the card that physically makes the connection between the computer and the network cable. These cards typically use an Ethernet connection.

Benefits of a Client/Server Network

Servers store all of the shared files for each user. Server s run file backups for shared resources. Servers manage user security and authentication. Servers manage printer sharing and acts as a central repository for printer drivers and settings. Servers manage other common resources such as email, web, databases, and system management.

Client/Server Networks

The more common type of network is a client server network. This type of network uses a central server running a network operating system. The server is dedicated to store shared files, run tasks and provide network services. A server is not a general user s machine. The computers that connect to the server, known as clients, are the machines users would use. The server acts as the "hub" of the network. It provides the services all users need and storage for sharing files. Common server network operating systems include Windows Server or Linux.

Segment

The process of separating certain portions of network traffic either for performance, security, or reliability reasons. Several ways to segment a network are subnetting, VLAN's, and hardware..

Transmission

The sending of data from one place to another by means of signals over a channel.

Data packets

The unit of data routed between an origin and a destination on the Internet or any other packet-switched network.

Workstation

Usually the same thing as a client. But a workstation is usually a business class PC that often has more powerful hardware than a home computer.

LAN technologies

are very diverse, but they all share some commonalities. All LANs have some sort of physical media that connect devices, interfaces to the individual devices, and protocols that transmit data across the network. Many LANs also include connectivity devices such as switches or routers. The size and scale of a LAN depends on the type, configuration, and number of devices involved.

WAN (wide area network)

in comparison to a MAN, is not restricted to a geographical location, although it might be confined within the bounds of a state or country. A WAN connects LANs together over WAN links. The LAN locations joined together by WAN links are called WAN sites. WANs are usually fast and often expensive. The Internet is an example of the largest and most well-known worldwide public WAN. WANs are usually connected by routers over high speed links.

LAN (Local area network)

is a computer network ranging in size from a few computers connected together in a single office or home, to hundreds or even thousands of devices spread across several buildings. They function to link computers together and provide shared access to printers, file servers, and other services. LANs in turn may be connected to larger networks, such as larger LANs or wide area networks (WANs).

MAN (metropolitan area network)

is larger than a LAN. It can span several buildings or a city or town. Also related is the term CAN or Campus Area Network which relates to a campus of networked buildings like a college or large business.