This glossary provides short definitions of terms related to instant messaging (IM) and other presence technologies.
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acceptable use policy (AUP) - a policy that a user must agree to follow in order to be provided with access to a network or to the Internet.
AIM (AOL instant messaging) - free messaging software that does not require AOL membership to use.
asynchronous - an adjective describing objects or events that are not coordinated in time and do not occur simultaneously.
buddy list (also called contact list) - presence technology that allows the user to see who on their list is offline, who is online, who is online but away from their computer, who has their phone turned off, who has their phone turned on, or who is currently talking on their phone.
buffer overflow - an increasingly common type of security attack on data integrity that exploits the fact that when too much data is written into a buffer, the extra data will spill over into the adjacent memory structure.
channel - a specific IRC chat group.
chat - text or voice messaging carried out in real-time.
chat abbreviations - abbreviations commonly used in instant messaging and SMS messaging.
chat room - a Web site, part of a Web site, or part of an online service that provides a venue for communities of users with a common interest to communicate in real time.
contact list - see buddy list
emoticon - a short sequence of keyboard letters and symbols, usually emulating a facial expression.
encryption - the conversion of data into a form, called a ciphertext, that cannot be easily understood by unauthorized people.
firewall - a set of related programs, located at a network gateway server, that protects the resources of a private network from users from other networks.
group chat - a Web site, part of a Web site, or part of an online service such as America Online, that provides a venue for several users with a common interest to communicate in real time.
ICQ - ("I Seek You") a program that will let you know when friends and contacts are also online on the Internet. ICQ allows you to page them, chat with them, initiate and participate in PC-to-PC calls, PC-to-phone and phone-to-phone calling cards calls.
identity management - a broad administrative area that deals with identifying individuals in a system and controlling their access to resources within that system by associating user rights and restrictions with the established identity.
IM worm - self-replicating malicious code that spreads in Instant Messenger (IM) networks.
instant messaging - the ability to easily see whether a chosen friend or co-worker is connected to the Internet and, if they are, to exchange messages with them.
interoperability - the ability of a system or a product to work with other systems or products without special effort on the part of the customer.
internet relay chat (IRC) - a system for chatting that involves a set of rules and conventions and client/server software.
Jabber - an initiative to produce an open source, XML-based instant messaging platform.
Lightweight Directory Access Protocol (LDAP) - a software protocol for enabling anyone to locate individuals and other resources, such as files and devices in a network, whether on the public Internet or on a corporate intranet.
multimedia messaging service (MMS) - allows for non-real-time transmission of various kinds of multimedia contents, such as images, audio, and video clips.
mobile node - an Internet-connected device whose location and point of attachment to the Internet may change frequently.
mobile IP - an Internet Engineering Task Force standard communications protocol designed to allow mobile device users to move from one network to another while maintaining their permanent IP address.
presence technology - a type of application that makes it possible to locate and identify a computing device wherever it might be, as soon as the user connects to the network.
real time - an adjective used to describe an application that updates information at the same rate it receives data -- analagous to a telephone conversation where both parties have the sense of being in the same room talking face to face.
RVP - a proprietary protocol development by Microsoft that extends the HTTP 1.1 protocol by adding additional command verbs which are used for presence information, subscription information, security, and privacy.
Sametime (renamed Lotus Instant Messaging and Web Conferencing) - a synchronous groupware application from Lotus for group collaboration over the Internet.
Sarbanes-Oxley Act (SOX) - legislation enacted in response to the high-profile Enron and WorldCom financial scandals to protect shareholders and the general public from accounting errors and fraudulent practices in the enterprise.
SIMPLE - SIP for Instant Messaging and Presence Leveraging Extensions
Session Initiation Protocol (SIP) - Internet Engineering Task Force standard protocol for initiating an interactive user session that involves multimedia elements such as video, voice, chat, gaming, and virtual reality.
Short Message Service (SMS) - a service for sending messages of up to 160 characters (224 characters if using a 5-bit mode) to mobile phones that use Global System for Mobile (GSM) communication.
Secure Sockets Layer (SSL) - a commonly-used protocol for managing the security of a message transmission on the Internet.
store and forward - Communication transmission between two entities that does not require that both applications be running and available at the same time.
synchronous - an adjective describing objects or events that are coordinated in time and occur simultaneously.
Transport Layer Security (TLS) - a protocol that ensures privacy between communicating applications and their users on the Internet.
Video over IP - allows video signals to be captured, digitized, streamed, and managed over IP networks.
videoconferencing - a live connection between people in separate locations for the purpose of communication, usually involving audio and often text as well as video.
Voice over IP - a term used in IP telephony for a set of facilities for managing the delivery of voice information using the Internet Protocol (IP).
WAP - a specification for a set of communication protocols to standardize the way that wireless devices, such as cellular telephones and radio transceivers, can be used for Internet access, including e-mail, the World Wide Web, newsgroups, and Internet Relay Chat (IRC).
XMPP - an open protocol for instant messaging and presence technology that's based on XML.
Yahoo! Messenger - free messaging service that uses the connection you have established with your Internet service provider (ISP).