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Handbook of Local Area Networks, 1998 Edition:Applications of LAN Technology Click Here! Search the site:   ITLibrary ITKnowledge EXPERT SEARCH Programming Languages Databases Security Web Services Network Services Middleware Components Operating Systems User Interfaces Groupware & Collaboration Content Management Productivity Applications Hardware Fun & Games EarthWeb sites Crossnodes Datamation Developer.com DICE EarthWeb.com EarthWeb Direct ERP Hub Gamelan GoCertify.com HTMLGoodies Intranet Journal IT Knowledge IT Library JavaGoodies JARS JavaScripts.com open source IT RoadCoders Y2K Info Previous Table of Contents Next THE VALUE OF VOICE AND VIDEO ON THE LAN There are essentially two main kinds of motivation for considering voice and/or video on the LAN: the need to support new types of application that involve real-time communications, and the desire to improve the overall cost-effectiveness of the local communications infrastructure. New Types of Applications Desktop videoconferencing, real-time multimedia collaboration, and video-based training are all examples of new kinds of applications that can benefit from the delivery of voice and video over the LAN. The uptake of desktop videoconferencing has been held back by a combination of high costs and the difficulty of delivering appropriate network services to the desktop. Standards-based H.320 desktop videoconferencing systems require costly video compression and ISDN interface hardware, as well as the provision of new ISDN connections at the desktop alongside the LAN and the phone system. New systems based on the H.323 standard and designed to run over the LAN will leverage the processing power of the latest PCs and the existing switched LAN infrastructure, to lower cost and simplify deployment dramatically. Desktop videoconferencing may be used either to support internal meetings and discussions between groups located at remote sites, or to support direct interaction with customers and clients. For example, some enterprises in the mortgage lending business use videoconferencing to conduct mortgage approval interviews with potential borrowers, so as to greatly reduce the overall time to complete a mortgage sale. Real-time collaboration applications, involving any mix of video and voice with data conferencing to support application sharing and interactive whiteboarding, provide a new way for individuals and small groups to collaborate and work together remotely in real time. This emerging class of applications, typified by Microsoft NetMeeting, is being evaluated by many enterprises, particularly for help desk applications. By contrast, video-based training is already widely used in enterprise LANs. By delivering self-paced video learning materials to the desktop, training needs can be met in a more timely and less disruptive fashion than traditional classroom methods. The growing popularity of these kinds of applications should be noted by network planners and designers. A pre-planned strategy for local LAN upgrades to support voice and video will reduce the lead time for the deployment of these applications, and enable the enterprise to move swiftly when the application need has been identified, to obtain the business benefits with the least possible delay. Infrastructure Efficienciesy A single local communications infrastructure based on a LAN that handles data, voice, and video has the potential to cost less to own and operate than separate PBX and data-only LAN infrastructures. The average capital cost of a fully featured PBX for large enterprises is between $700 and $750 per user, according to a leading US telecommunications consultancy, TEQConsult Group. Furthermore, this is expected to rise slightly over the next few years as users demand more sophisticated features from their phone system. It is not difficult to see how a switched LAN that has been enhanced to handle voice could provide a solution for telephony at a fraction of this cost. Most large PBX installations are equipped with additional facilities such as voice mail and Interactive Voice Response systems for auto-attendant operation. These systems are typically connected directly to the PBX via proprietary interfaces, and they too represent major capital investments. With voice on the LAN, such voice processing applications could be based on open server platforms and leverage the low-cost processing power and disk storage that is a feature of today’s PC server market, thereby lowering the system’s capital cost still further. Separate PBX and LAN infrastructures each incur their own management and operational costs. For example, moves, adds and changes require separate actions to patch physical LAN and voice connections, and to update LAN logon and voice directories. With telephony provided over a voice-enabled LAN supporting combined directory services, the management effort required to administer moves and changes would be substantially reduced. These cost of ownership benefits come with a raft of usability improvements for telephony. The PC (with phone handset attached) becomes the communications terminal for making and receiving phone calls, and the processing power and graphical user interface of the PC can be leveraged to provide point-and-click call launch and manipulation. Features of PBXs such as call transfer, divert, and hold, which are hard to invoke from phone keypad, become very easy to use from a Windows interface. Incoming callers can be identified on the PC display by matching Calling Line Identifier with directory entries. And with voice mail and E-mail supported on a unified messaging platform such as Microsoft Exchange or Lotus Notes, all messages are accessible and manageable via a single user interface. These usability benefits for voice telephony over the LAN extend also to videoconferencing—a single consistent user interface may be applied to both video and voice-only calls. Previous Table of Contents Next Use of this site is subject certain Terms & Conditions. Copyright (c) 1996-1999 EarthWeb, Inc.. All rights reserved. Reproduction in whole or in part in any form or medium without express written permission of EarthWeb is prohibited. Please read our privacy policy for details.



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