Packet

 A piece of a message transmitted over a packet-switching network. See under packet switching. One of the key features of a packet is that it contains the destination address in addition to the data. In IPnetworks, packets are often called datagrams.

Local area network 

The library terminals that display book information would connect over a local area network. Wide area network (WAN) technologies connect a smaller number of devices that can be many kilometers apart.

wide area network 

The library terminals that display book information would connect over a local area network. Wide area network (WAN) technologies connect a smaller number of devices that can be many kilometers apart

Node

 A node is anything that is connected to the network. While a node is typically a computer, it can also be something like a printer or CD-ROM tower.

 Media Access Control (MSC)

his is the physical address of any device -- such as the NIC in a computer -- on the network. The MAC address, which is made up of two equal parts, is 6 bytes long. The first 3 bytes identify the company that made the NIC. The second 3 bytes are the serial number of the NIC itself.

 IP Address

An IP Address is a unique identifier for devices and websites online.  It enables devices to find one another, and send and receive data, and also contains information about the physical location of the device.

Bus Topology

Ring Topology

Like a bus network, rings have the nodes daisy-chained. The difference is that the end of the network comes back around to the first node, creating a complete circuit. In a ring network, each node takes a turn sending and receiving information through the use of a token. The token, along with any data, is sent from the first node to the second node, which extracts the data addressed to it and adds any data it wishes to send. Then, the second node passes the token and data to the third node, and so on until it comes back around to the first node again. Only the node with the token is allowed to send data. All other nodes must wait for the token to come to them.

Network Token

 In programming languages, a single element of a programming language. For example, a token could be a keyword, an operator, or a punctuation mark.

Star Topology

In a star network, each node is connected to a central device called a hub. The hub takes a signal that comes from any node and passes it along to all the other nodes in the network. A hub does not perform any type of filtering or routing of the data. It is simply a junction that joins all the different nodes together.

Tree Topology

Protocol

There are a variety of standard protocols from which programmers can choose. Each has particular advantages and disadvantages; for example, some are simpler than others, some are more reliable, and some are faster.

Peer-Peer Architecture

Often referred to simply as peer-to-peer, or abbreviated P2P, a type of network in which each workstation has equivalent capabilities and responsibilities. This differs from client/server architectures, in which some computers are dedicated to serving the other machines in the system. Peer-to-peer networks are generally simpler, but they usually do not offer the same performance under heavy loads.

Client/Server Architecture

Client-server architecture (client/server) is a network architecture in which each computer or process on the network is either a client or a server.

Servers are powerful computers or processes dedicated to managing disk drives (file servers), printers (print servers), or network traffic (network servers). Clients are PCs or workstations on which users run applications. Clients rely on servers for resources, such as files, devices, and even processing power.