Appendix E connectivity: the business value of a networked world

Networking elements creating a connected world

local area network (LAN)

Connects a group of computers in proximity, such as in an office building, school, or home.

wide area network (WAN)

Spans a large geographic area such as a state, province, or country.

attenuation

Represents the loss of a network signal strength measured in decibels (dBs) and occurs because the transmissions gradually dissipate in strength over longer distances or because of radio interference or physical obstructions such as walls.

repeater

Receives and repeats a signal to reduce its attenuation and extend its range.

metropolitan area network (MAN)

A large computer network usually spanning a city.

national service providers (NSPs)

Private companies that own and maintain the worldwide backbone that supports the Internet.

regional service providers (RSPs)

Offer Internet service by connecting to NSPs, but they also can connect directly to each other.

Internet topology

bandwidth

The maximum amount of data that can pass from one point to another in a unit of time.

bit

The smallest element of data. It has a value of either 0 or 1.

bit rate (or data rate)

The number of bits transferred or received per unit of time.

modem

A device that enables a computer to transmit and receive data.

broadband

A high-speed Internet connection that is always connected.

digital subscriber line (DSL)

Provides high-speed digital data transmission over standard telephone lines using broadband modem technology, allowing both Internet and telephone services to work over the same phone lines.

high-speed Internet cable connection

Provides Internet access by using a cable television company’s infrastructure and a special cable modem.

cable modem (or broadband modem)

A type of digital modem used with high-speed cable Internet service.

telecommuting (virtual workforce)

Allows users to work from remote locations such as a home or hotel, using high-speed Internet to access business applications and data.

broadband over power line (BPL)

Technology that makes possible high-speed Internet access over ordinary residential electrical lines and offers an alternative to DSL or high-speed cable modems.

packet

A single unit of binary data routed through a network.

standard packet format

Includes a packet header, packet body containing the original message, and packet footer.

packet header

Lists the destination (for example, in IP packets the destination is the IP address) along with the length of the message data.

packet footer

Represents the end of the packet or transmission end.

traceroute

A utility application that monitors the network path of packet data sent to a remote computer.

proxy

Software that prevents direct communication between a sending and a receiving computer and is used to monitor packets for security reasons.

protocol

A standard that specifies the format of data, as well as the rules to be followed during transmission.

file transfer protocol (FTP)

A simple network protocol that allows the transfer of files between two computers on the Internet.

transmission control protocol/Internet protocol (TCP/IP)

Provides the technical foundation for the public Internet, as well as for large numbers of private networks.

IP address

A unique number that identifies where computers are located on the network.

Examples of TCP/IP

dynamic host configuration protocol (DHCP)

Allows dynamic IP address allocation so users do not need a preconfigured IP address to use the network.

domain name system (DNS)

Converts IP address into domains, or identifying labels that use a variety of recognizable naming conventions.

Internet domains

network convergence

The efficient coexistence of telephone, video, and data communication within a single network, offering convenience and flexibility not possible with separate infrastructures.

The benefits of network convergence

unified communications (UC)

The integration of communication channels into a single service.

Voice over IP (VoIP)

Uses IP technology to transmit telephone calls.

voIP Connectivity

peer-to-peer (P2P) network

A computer network that relies on the computing power and bandwidth of the participants in the network rather than on a centralized server.

Internet Protocol TV (IPTV)

Distributes digital video content by using IP across the Internet and private IP networks.

IPTV Components

Intranet uses

extranet

An extension of an intranet that is only available to authorized outsiders, such as customers, partners, and suppliers.

virtual private network (VPN)

Companies can establish direct private network links among themselves or create private, secure Internet access, in effect a private tunnel within the Internet.

Using a VPN