Glossary

Access Point
A hardware device that serves as a communications hub to provide a wireless connection to a wireless-enabled computer. The range of an Access Point can be up to 300 feet.

Bandwidth
The amount of data that can be transmitted in a fixed amount of time. For digital devices, the bandwidth is usually expressed in bits per second (bps) or bytes per second. For analog devices, the bandwidth is expressed in cycles per second, or Hertz (Hz).

Bps (bits per second)
In data communications, bits per second (abbreviated bps) is a common measure of data speed for computer modems and transmission carriers. As the term implies, the speed in bps is equal to the number of bits transmitted or received each second. The duration of a data bit, in seconds, is inversely proportional to the digital transmission speed s in bps:
d = 1/s. Larger units are sometimes used to denote high data speeds. One kilobit per second (abbreviated Kbps in U.S.; kbps elsewhere) is equal to 1,000 bps. One megabit per second (Mbps) is equal to 1,000,000 bps or 1,000 kbps. Computer modems for twisted pair telephone lines usually operate at speeds between 14.4 and 57.6 kbps. The most common speeds are 28.8 and 33.6 kbps. So called "cable modems," designed for use with TV cable networks, can operate at more than 100 kbps. Fiber optic modems are the fastest of all; they can send and receive data at many Mbps. The bandwidth of a signal depends on the speed in bps. With some exceptions, the higher the bps number, the greater is the nominal signal bandwidth. (Speeded bandwidth are, however, not the same thing.) Bandwidth is measured in standard frequency units of kilohertz (kHz) or megahertz (MHz).

Browser
Short for Web browser, a software application used to locate and display Web pages. The two most popular browsers are Netscape Navigator and Microsoft Internet Explorer. Both of these are graphical browsers, which means that they can display graphics as well as text. In addition, most modern browsers can present multimedia information, including sound and video, though they require plug-ins for some formats.

Broad band
Broadband refers to telecommunication that provides multiple channels of data over a single communications medium, typically using some form of frequency or wave division multiplexing.

Bytes
Abbreviation for binary term, a unit of storage capable of holding a single character. On almost all modern computers, a byte is equal to 8 bits. Large amounts of memory are indicated in terms of kilobytes (1,024 bytes), megabytes (1,048,576 bytes), and gigabytes (1,073,741,824 bytes). A disk that can hold 1.44 megabytes, for example, is capable of storing approximately 1.4 million characters, or about 3,000 pages of information.
Data Transfer rate
A data transfer rate (or often just data rate) is the amount of digital data that is moved from one place to another in a given time, usually in a second's time. The data transfer rate can be viewed as the speed of travel of a given amount of data from one place to another. In general, the greater the bandwidth of a given path, the higher the data transfer rate.

Download and Upload
Downloading is the transmission of a file from one computer system to another, usually smaller computer system. From the Internet user's point-of-view, to download a file is to request it from another computer (or from a Web page on another computer/server) and to receive it. Examples of download are receiving a mail, downloading/receiving a song/ software/chat client, receiving a chat message etc.

Uploading is transmission in the other direction: from one, usually smaller computer to another computer. From an Internet user's point-of-view, uploading is sending a file to a computer that is set up to receive it. People who share images with others on bulletin board systems (BBS) upload files to the BBS. Examples of upload are attaching a file to mail and sending it, requesting any URL/web page address (say typing www.spectranet.com and pressing the enter button), sending a chat message, sending an email etc.
The File Transfer Protocol (FTP) is the Internet protocol for downloading and uploading files and a number of special applications can furnish FTP services for you. (However, if you are downloading through a Web page, the FTP request is set up for you by the Web page. You are usually asked where you want the downloaded file placed on your hard disk, and then the downloading transmission takes place.)
When you send an attached file with an e-mail note, this is just an attachment, not a download or an upload. In practice, many people use "download" and "upload" rather indiscriminately so you just have to understand the context. For example, if someone says to you "Download (or upload) such--and-such a file to me by e-mail," they clearly mean "Send it to me as an attachment."
In general, from the ordinary workstation or small computer user's point-of-view, to download is to receive a file and to upload is to send a file.

Dial-up Access
Refers to connecting a device to a network via a modem and a public telephone network. Dial-up access is really just like a phone connection, except that the parties at the two ends are computer devices rather than people. Because dial-up access uses normal telephone lines, the quality of the connection is not always good and data rates are limited. In the past, the maximum data rate with dial-up access was 56 Kbps (56,000 bits per second).
Ethernet
A local-area network (LAN) protocol developed by Xerox Corporation in cooperation with DEC and Intel in 1976. Ethernet uses a bus or star topology and supports data transfer rates of 10 Mbps. The Ethernet specification served as the basis for the IEEE 802.3 standard, which specifies the physical and lower software layers. Ethernet uses the CSMA/CD access method to handle simultaneous demands. It is one of the most widely implemented LAN standards.
A newer version of Ethernet, called 100Base-T (or Fast Ethernet), supports data transfer rates of 100 Mbps. And the newest version, Gigabit Ethernet supports data rates of 1 gigabit (1,000 megabits) per second.

Hubs
A common connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.

IP (Internet Protocol)
The Internet Protocol (IP) is the method or protocol by which data is sent from one computer to another on the Internet. Each computer (known as a host) on the Internet has at least one address that uniquely identifies it from all other computers on the Internet. When you send or receive data (for example, an e-mail note or a Web page), the message gets divided into little chunks called packets. Each of these packets contains both the sender's Internet address and the receiver's address. Any packet is sent first to a gateway computer that understands a small part of the Internet. The gateway computer reads the destination address and forwards the packet to an adjacent gateway that in turn reads the destination address and so forth across the Internet until one gateway recognizes the packet as belonging to a computer within its immediate neighborhood or domain. That gateway then forwards the packet directly to the computer whose address is specified.
Because a message is divided into a number of packets, each packet can, if necessary, be sent by a different route across the Internet. Packets can arrive in a different order than the order they were sent in. The Internet Protocol just delivers them. It's up to another protocol, the Transmission Control Protocol (TCP) to put them back in the right order.
IP is a connectionless protocol, which means that there is no established connection between the end points that are communicating. Each packet that travels through the Internet is treated as an independent unit of data without any relation to any other unit of data. (The reason the packets do get put in the right order is because of TCP, the connection-oriented protocol that keeps track of the packet sequence in a message.)

Internet telephony
A category of hardware and software that enables people to use the Internet as the transmission medium for telephone calls. For users who have free, or fixed price Internet access, Internet telephony software essentially provides free telephone calls any where in the world. To date, however, Internet telephony does not offer the same quality of telephone service as direct telephone connections.
There are many Internet telephony applications available. Some, like CoolTalk and NetMeeting, come bundled with popular Web browsers. Others are stand-alone products. Internet telephony products are sometimes called IP telephony, Voice over the Internet (VOI) or Voice over IP (VOIP) products.

Kbps
In the U.S., Kbps stands for kilobits per second (thousands of bits per second) and is a measure of bandwidth (the amount of data that can flow in a given time) on a data transmission medium. Higher bandwidths are more conveniently expressed in megabits per second (Mbps, or millions of bits per second) and in gigabits per second (Gbps, or billions of bits per second).

Kilobyte
As a measure of computer memory or storage, a kilobyte (KB or Kbyte*) is approximately a thousand bytes (actually, 2 to the 10th power, or decimal 1,024 bytes).

LAN (Local Area Network)
A local area network (LAN) is a group of computers and associated devices that share a common communications line or wireless link and typically share the resources of a single processor or server within a small geographic area (for example, within an office building). Usually, the server has applications and data storage that are shared in common by multiple computer users. A local area network may serve as few as two or three users (for example, in a home network) or many as thousands of users (for example, in an FDDI (Fiber Distributed Data Interface) network).

Laptop Computer
A small, portable computer -- small enough that it can sit on your lap. Nowadays, laptop computers are more frequently called notebook computers.
Media Access Control (MAC) address
Short for Media Access Control address, a hardware address that uniquely identifies each node of a network. In IEEE 802 networks, the Data Link Control (DLC) layer of the OSI Reference Model is divided into two sub layers: the Logical Link Control (LLC) layer and the Media Access Control (MAC) layer. The MAC layer interfaces directly with the network media. Consequently, each different type of network media requires a different MAC layer.

NIC (Network Interface Card)
A network interface card (NIC) is a computer circuit board or card that is installed in a computer so that it can be connected to a network. Personal computers and workstations on a local area network (LAN) typically contain a network interface card specifically designed for the LAN transmission technology, such as Ethernet. Network interface cards provide a dedicated, full-time connection to a network.

On-line
Users are considered on-line when they are connected to the internet through a browser, or any other program that connects them to the internet.

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

PCMCIA
Expansion cards now referred to as "PC Cards" were originally called "PCMCIA Cards". It is A removable, credit-card-sized memory or I/O device that fits into a Type 2 PCMCIA standard slot, PC Cards are used primarily in PCs, portable computers, PDAs and laptops. PC Card peripherals include Wi-Fi cards, memory cards, modems, NICs, hard drives, etc.

PDA (personal digital assistant)
Mobile, handheld devices-such as the Palm series and Handspring Visors-that give users access to text-based information. Users can synchronize their PDAs with a PC or network; some models support wireless communication to retrieve and send e-mail and get information from the Web

Throughput
The amount of data transferred from one place to another or proce Error! No index entries found.ssed in a specified amount of time. Data transfer rates for disk drives and networks are measured in terms of throughput. Typically, through puts are me.

VoIP
Voice over IP - that is, voice delivered using the Internet Protocol) is a term used in IP telephony for a set of facilities for managing the delivery of voice information using the Internet Protocol (IP). In general, this means sending voice information in digital form in discrete packets rather than in the traditional circuit-committed protocols of the public switched telephone network (PSTN). A major advantage of VoIP and Internet telephony is that it avoids the tolls charged by ordinary telephone service assured in Kbps, Mbps and Gbps.

Wi-Fi (shorthand for "wirless fidelity")
Is the common term for a high-frequency wireless local-area network (WLAN). The term used generically when referring of any type of 802.11 network, whether 802.11b, 802.11a, dual-band, etc. Wi-Fi operates in the 2.4 GHz range offering data speeds up to 11 megabits per second

WISP (wireless Internet service provider)
A vendor that specializes in providing wireless Internet access.