Technical Terms
ADN: (Advanced Digital Network) A dedicated line service capable of transmitting data, video, and other digital signals with exceptional reliability (offered as a premium service by communications companies); usually ADN refers to speeds at or above 56 kilobits per second (Kbps).
ADSL: (Asymmetric Digital Subscriber Line) A form of DSL (Digital Subscriber Line) in which the bandwidth available for downstream connection is significantly larger then for upstream. Although designed to minimise the effect of crosstalk between the upstream and downstream channels this setup is well suited for web browsing and client-server applications as well as for some emerging applications such as video on demand.
Anonymous FTP: The ability to access a remote computer system on which one does not have an account, via the Internet's FTP
ASCII: (American Standard Code for Information Interchange)
The standard worldwide coding system using 7 or 8 bits that assigns numeric values to up to 256 characters, including letters, numerals, and punctuation represented by a 7-digit binary number.
Backbone: A network of communication transmission that carries major traffic between smaller networks
Bandwidth: The data-transfer capacity, or speed of transmission, of a digital communications system as measured in bits per second (bps). (For a complete definition, see Microsoft Computer Dictionary, Fourth Edition, page 42.)
Baud Rate: The number of bits a modem can send or receive per second.
BBS: (bulletin board system)
A computer system equipped with one or more modems or other means of network access that serves as an information and message-passing center for remote users.
Binary: In an FTP client program, the command that instructs the FTP server to send or receive files as binary data. (For a complete definition, see Microsoft Computer Dictionary, Fourth Edition, page 48.)
Bit: When you hear people talk about a computer running on a bunch of ones and zeros, a bit is where they’re kept. “Bit” is an abbreviated form of “binary digit,” the smallest unit of information a computer can recognize. A bit holds a single piece of information, either a one or a zero, on or off, yes or no.
Bookmark: Just like the paper one you stick into a printed book, a bookmark is a placeholder to a particular URL, Web address, or place in a document, that you set for ready access later. Bookmarks are typically used to record a site you want to return to or one you visit regularly.
Bot: You can think of bots as virtual clones. Essentially computer programs that behave as users, bots can make it look like you’re still in a chat room when you’re not, or they can visit Web sites and gather information for you. The major search engines use bots in their efforts to index the Web.
Bps: (bits per second) This is the measure of a modem’s signaling speed. However, the only term you’ll hear describing new modems is Kbps, for kilobits per second—as in 28.8 Kbps, meaning 28,800 bits per second
BRIDGE: A device which forwards traffic between network segments based on data link layer information. These segments would have a common network layer address. Every network should only have one root bridge.
Broadband: Broadband, also known as wideband. This would be any communications channel that can carry signals with multiple frequencies. Broadband communications permit several independent signals to travel across a single cable simultaneously without getting into each other’s way.
Byte: A byte is comprised of eight bits that represents a single element of data. In text files, each character is typically represented by a single byte. Bytes are most often used in describing file size and data storage in general (as in kilobyte, megabyte, and so on). How many bytes a program takes up tells you how much of your hard disk capacity the program is utilizing.
Case-sensitive: Case-sensitive refers to a requirement for you to type with strict attention to uppercase or lowercase characters. If an application interprets the letters “UPS” and “ups” as the same, it is not case-sensitive. If it finds them different, then it is.
Chat: Chat as it is defined here s in the online sense. Online chat is just like chatting with friends, except the participants can be anywhere in the world, and the words are typed instead of spoken. Some chat areas can Interpret these words and convert them to sound for the user to hear.
Clickstream: This is the trail of Web site links you traveled to get to a given site. Internet merchants devising marketing schemes to lure you to their sites are very curious about the nature of your clickstream. (And they can pull this information from your browser easily without your knowledge.)
Compression: (.zip, .sea, .sit, .tar) Any of various ways of squeezing a file down to a smaller size. Compressed files save you time, as they transfer much more quickly Software that compresses files, such as the shareware utility PKZIP.EXE or Stufflt, looks for repetition in the bytes comprising a file and assigns various codes that represent the repeated bytes—without storing the actual bytes in the file’s compressed version. Another form of compression, disk compression, refers to software that compresses all data on a given hard disk.
Cookie: A cookie is a small piece of information that a Web server (such as the one that holds the Web shopping mall) sends to your browser to hold onto until it’s time for the server to read it. For instance, the cookie made while you shop around a Web mall contains a list of the items you’re planning to purchase. When you head to the checkout desk, the server collects the cookie from your browser to see what you’re buying. Cookies also have expiration dates and instructions about which sites can “eat” them, along with security information to protect your buying info.
Cracker: Is a word co-opted by the hacker community in the mid-1980s to describe someone who tries to break into a computer system by cracking passwords. The difference between hackers and crackers (other than the too-pat distinction of honest vs. dishonest) is one of technical prowess: Hackers—the malicious ones, anyway—break into systems through their sheer intelligence and mastery of the technologies involved. Crackers (at least according to hackers) break into the same systems through a little bit of knowledge and a whole lot of luck.
Crawler: Also referred to as a robot, wanderer, or spider is a type of bot that “crawls” the Web collecting URLs and other information from Web pages. Search engines are built around the information that crawlers retrieve.
Cross-posting: This is the practice of posting a message in more than one Internet newsgroup, which is done when the creator of the message believes the topic worthy of interest to more than one newsgroup. Cross-posting can be rewarding when the creator is selective enough to post the message only where appropriate, and not in a way that blankets myriad newsgroups
Dial-up: Dial-up describes the kind of connection you have if you dial a number through your computer to connect to your ISP Dial?up differentiates standard phone line connections from other, higher?speed lines that maintain a constant connection between two points, such as T1 lines.
Digital: Digital signifies something that has only two states, 1 and 0. The difference between digital and analog is the difference between a light bulb controlled by an on/off switch and one controlled by a dimmer. Of course, your computer is digital, and it needs a lot more information than just a one or a zero to keep it running. It uses digital information, made up of a complex series of ones and zeros, to get the job done.
Directory: The first definition of “directory” is a categorized and hierarchically organized listing of Web sites. Yahoo! is an example of this kind of directory. The second definition refers to a hard disk’s organizational levels. Your PC’s hard disk is organized into directories to help users (and programs) find data and other programs. Web servers are also organized into directories.
DNS: A computer called a DNS (Domain Name Server). handles the the mapping to domains. When you click on (or type in) a URL, it gets sent to the DNS to figure out where, say, “www.faia.com” (that’s us!) might be located. If it knows the location off the bat, it sends you there; otherwise, it asks other DNSs until it figures out the directions to (in our case) a computer in Cambridge, Massachusetts. Sometimes you’ll see your browser showing a small message that says it’s “looking up” a site you’ve requested; the DNS is on the case.
Domain: Just as a PC’s file extensions (such as .xls for MS Excel files) give some indication of what kind of file it is, the last part of an Internet site’s domain name tells what kind of site it is. The most rapidly expanding of these is “.com,” as in www.faia.com, our address. (That stands for “commercial.”) Other common ones include .edu, for educational institutions, .gov for government, and .mil, for military sites
Domain Name: The last two parts of an Internet address. In our address, www.faia.com, the “faia.com” part tells the server the machine from which we’d like to retrieve our information. Although “www” is the most common precursor, you will see sites with other precursors (home. netscape.com), or with no precursor at all, such as leary.com.
DOS: An operating system that resides on a disk.
DS1: A DS level and framing specification for synchronous digital streams, over circuits in the North American
DSL: (Digital Subscriber Line) A form of digital telecommunications protocols designed to allow high speed data communication over the existing copper telephone lines.
Emoticons: This is the name for all those little sideways smiley faces—and other non-smiling variations on the theme—that you see sprinkled throughout email messages and Usenet postings. At first glance they may seem shallow: Since when has the English language needed graphical assistance? Keep in mind, though, how ridiculously easy it can be to give a wrong impression when batting out message replies, particularly if you’re doing it online without editing yourself. A smiley face or a substitute tells the message’s recipients' that you’re only kidding or, in certain cases, being sarcastic.
Encryption: Computer telecommunications are notoriously insecure. Because of this troublesome fact, if you want to transmit something you don’t want anyone else to see (such as credit card information, passwords, or trade secrets) you have to use one of a variety of encryption schemes which convert files into a secret code before they are transmitted. At the other end if all is going well, your intended recipient’s software will “decrypt” the file for their use
Extension: PCs use file extensions—a dot (period) and two, three, or four letters—at the end of file names to keep track of what kind of file it is. For instance, Microsoft Word files usually have a “.doc” extension, while Web pages, which use hypertext markup language, have an “.htm” or “.html” extension. Recognizing file extensions helps you when you’re trying to figure out what a particular file is. For instance, if someone sends you a file that has a .cfm file extension, you know that it is associated with a cold fusion template.
FAQs: (Frequently Asked Questions) Files that commonly are maintained at Internet sites to answer frequently asked questions so that site managers do not have to repeatedly answer the same questions over and over.
File Format: Files are created in particular ways by particular programs. For instance, you can’t open a Microsoft Word file in Adobe Photoshop. On PCs, there is a three letter extension on every file that indicates what type of file it is. Some common “file formats” are “.txt,” for text files; “.doc,” for Word documents; “.jpg,” for JPEG graphics; and “.gif,” for GIF graphics.
FLAPPING ROUTER: A router that transmits routing updates alternately advertising a destination network first via one route, then via a different route.
Flapping routers are identified on more advanced protocol analysers such as the Network General (TM) Sniffer.
Frame: Frames are a technology introduced in Netscape 2.0 that allows Web weavers to break the browser window into several smaller windows, each of which can load different things. This means that designers can create navigation bars and ads that stay with you as you click through a site.
Freeware: Freeware is software whose author lets anyone use it freely without paying for it. Freeware differs from “public domain” software in that, while both are free of charge, a freeware program’s author retains the copyright. In other words, you’re not allowed to alter the code, incorporate it into software you’ve written, or pass it off as your own, whether for profit or not. Freeware authors make their software available for the good of the community. The quality, of course, varies; some freeware is excellent, and some is, well, worth what you paid for it.
FTP: You’ve probably put software on your computer by putting diskettes into a disk drive. Online, you can get software by downloading it. The software sits on Computer X; you use your browser or an FTP (file transfer protocol) program to find and retrieve the software to your computer. If you had software you wanted to send to another computer, you’d reverse the process; this is known as “uploading.”
GATEWAY: A deprecated term for a device that enables data to flow between different networks (forming an internet).
GIF: Most of the graphics you run across on the Web will be in the GIF (Graphics Interchange Format) format. Tthese files are called “GIFs” for short, a file type that is readable by most graphics programs. You can tell a file is a GIF by looking at its extension. If its name is something like “filename.gif,” then you guessed it—it’s a GIF : GIF stands for . Compare with JPEG.
Gigabyte: A gigabyte is the next largest unit of data storage above a megabyte. A gigabyte is 1,024 megabytes, which means it’s over a billion bytes. (e.g., a megabyte is 1,024 kilobytes, and a kilobyte is 1,024 bytes).
Graphic: “Graphic” refers to any file that stores an electronic version of a picture. The format used may range in detail from a black and white line art drawing to a high resolution photo using millions of colors. Graphic file types include .EPS, .GIF, .JPG, .PCX, and .TIF.
ISDN: (Integrated Services Digital Network). A set of communications standards allowing a single wire or optical fibre to carry voice, digital network services and video.
OC3: A SONET rate of 3 * 51.84 = 155.52 megabits per second, which matches STS-3.
PACKET SNIFFER: A network monitoring tool that captures data packets and decodes them using built-in knowledge of common protocols. Sniffers are used to debug and monitor networking problems.
ROUTER: A device which forwards packets between networks. The forwarding decision is based on network layer information and routing tables, often constructed by routing protocols.
SONET: (Synchronous Optical NETwork) A broadband networking standard based on point-to-point optical fibre networks. SONET will provide a high-bandwidth "pipe" to support ATM-based services.
T1: A digital carrier facility used to transmit a DS1 formatted digital signal at 1.544 megabits per second
T3: A digital carrier facility used to transmit a DS3 formatted digital signal at 44.736 megabits per second
TCPIP: (Transmission Control Protocol/Internet Protocol) A communications protocol developed under contract from the U.S. Department of Defense to internetwork dissimilar systems. Invented by Vinton Cerf and Bob Kahn, this de facto Unix standard is the protocol of the Internet and has become the global standard for communications.
DHCP: Software that automatically assigns IP addresses to client stations logging onto a TCP/IP network. It eliminates having to manually assign permanent IP addresses. DHCP software typically runs in servers and is also found in network devices such as ISDN routers and modem routers that allow multiple users access to the Internet. Newer DHCP servers dynamically update the DNS servers after making assignments. See APIPA, DNS, DDNS and WINS.
APIPA: Automatic Private IP Addressing) A feature in Windows DHCP processing that assigns a class B IP address in the 169.254.0.0 range to the client when a DHCP server is unavailable. Designed for small non-routable networks, if a DHCP server becomes available afterwards, the APIPA address is replaced with one from the DHCP server. See DHCP.
WINS: Windows Internet Naming Service) Name resolution software from Microsoft that runs in Windows NT and 2000 servers. It converts NetBIOS names to IP addresses. Windows machines that are named as a PC in a workgroup rather than in a domain use NetBIOS names, which must be converted to IP addresses if the underlying transport protocol is TCP/IP.
PING: (Packet INternet Groper) An Internet utility used to determine whether a particular IP address is online by sending out a packet and waiting for a response. Ping is used to test and debug a network as well as see if a user is online. Ping also functions like a domain name (DNS) server, because "pinging" a domain name will return its IP address.
RSS: Short for RDF Site Summary or Rich Site Summary, an XML format for syndicating Web content. A Web site that wants to allow other sites to publish some of its content creates an RSS document and registers the document with an RSS publisher. A user that can read RSS-distributed content can use the content on a different site. Syndicated content includes such data as news feeds, events listings, news stories, headlines, project updates, excerpts from discussion forums or even corporate information. RSS was originally developed by Netscape.
Blogs: A collaborative Web site comprised of the perpetual collective work of many authors. Similar to a blog in structure and logic, a wiki allows anyone to edit, delete or modify content that has been placed on the Web site using a browser interface, including the work of previous authors. In contrast, a blog, typically authored by an individual, does not allow visitors to change the original posted material, only add comments to the original content
Wikis: A collaborative Web site comprised of the perpetual collective work of many authors. Similar to a blog in structure and logic, a wiki allows anyone to edit, delete or modify content that has been placed on the Web site using a browser interface, including the work of previous authors. In contrast, a blog, typically authored by an individual, does not allow visitors to change the original posted material, only add comments to the original content.
SEMCI: Single-Entry Multiple-Carrier Interface (SEMCI) Enables agents to send and receive data seamlessly by entering it only once in their management systems.To date, it continues to lag among insurers and distributors.
