Instant messaging software, or IM, enables a user to create a kind of private chat room with another individual in order to communicate in real time over the Internet, like a telephone conversation but using text-based communication.

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The software also alerts a user to whether somebody on his or her private list is online. They then can initiate a chat session with that particular individual.

Instant messaging is tremendously popular as a consumer end product, and is offered as a service by providers ranging from information portals to open source developers. And the technology has increasingly been adopted by enterprise to provide a real-time collaboration platform.

Microsoft (microsoft.com) now offers an IM product entitled Live Communications Server, which provides encrypted, enterprise-grade instant messaging and presence capabilities within an organization, as well as integration with the Microsoft Office software suite.

With Microsoft's product, two or more organizations can share IM and presence awareness in real time in an encrypted, authenticated and managed environment.

Live Communications Server users also can share presence information and IM with suppliers and customers using MSN, AOL and Yahoo! public IM networks, creating a channel for bringing geographically dispersed employees together.

Microsoft's product can also allow end users to connect to presence and IM capabilities when they are outside the corporate network, whether working from home or on the road, or visiting customers or partners. Access is provided in a more secure and authenticated manner through the use of standard firewall ports, without the need to establish a virtual private network.

Live Communication Server is high-end solution designed for large enterprises that want to deploy IM capabilities upon their internal networks. Active user capacity allows up to 15,000 active IM users per server. The server is quite expensive however: the standard version of Microsoft's Live Communications Server costs $750, while the enterprise version starts at $3,000.

For the smaller businesses that want to use IM capabilities, the open source Jabber server (jabber.org) package is the more accessible and affordable choice. Like Microsoft's solution, Jabber allows people and systems to exchange important information in real-time.

Because Jabber is XML-based, and is available freely as open source, some outsourced hosting service providers elect to offer Jabber IM as an option. This differs from the Microsoft model, in which the IM server is hosted from within the organization.

Service provider Dreamhost (dreamhost.com) is a prominent proponent of the service. The firm offers IM hosting capacity to individual end-users with every account. A novice systems administrator can also easily install Jabber on any standard unmanaged dedicated server. This makes the software package popular, since it can be installed on equipment from nearly any consumer-grade Web host.

Jabber does have enough extensibility to handle enterprise-class messaging, however. Jabber, Inc. (jabber.com) offers enhanced software that allows IM to function through a Web browser, not just via its own IM client.

Jabber WebClient is a commercial-grade cross-platform instant messaging client designed to let users participate in Jabber IM communities using their Web browsers, without installing client-side software. As a standalone, branded client, or as an IM function embedded into a portal page, the WebClient delivers cross-platform access to audiences when no desktop installation is desired.

Because it is browser-based, it can be customized to deliver enterprise or service provider content from standard HTML content feeds. Whether used as part of a customer service application, embedded into a corporate portal, or enabled for external employee access to the internal network, the WebClient is a convenient, centrally controlled option for Jabber Extensible Instant Messaging.

Jabber Extensible Instant Messaging is the proprietary add-on to the Jabber IM platform. While it does cost some money to deploy, it is a popular alternative. BellSouth licensed Jabber, Inc. product in order to launch instant messaging service to BellSouth Internet Services' more than one million customers. In addition, Jabber, Inc. is working with BellSouth to develop the next generation of presence-enabled offerings for its consumer and business/enterprise markets.