HVAC Control in the New Millennium.pdf - HVAC.Amickracing

HVAC Control in the New MillenniumActiveX component is actually a program that can access a Windowsbasedcomputer with the same privileges as any program. Honeywelluses several security measures:• digital signing of components gives assurance to users of the authenticityof the controls,• integrated NT security provides user authentication through thesystem and• the kerberos 5-based security available in Windows 2000.ActiveX and JavaActiveX is still proprietary to Microsoft, so to connect to othersystems, there may be the need to support both ActiveX and Java. CubeTechnology supports Microsoft technologies and their evolution towardActiveX and COM protocols in products like the CUBE-WEB modulewhich has the multiplatform benefits of Java.PC Soft also uses Java for its Internet-enabled applications. Thisprovides the ability to run on many different operating systems whichis a limitation of ActiveX when accessed by a browser.Fisher-Rosemount has built its DeltaV control system primarilywith OPC, but Java is used in its DeltaV Web Server to provide Intranetconnectivity. Fisher-Rosemount also has a DeltaV Web Server tool whichallows users to convert DeltaV operator graphics and trends into readonlyWeb pages. This permits access to DeltaV operating informationusing standard Internet browsers on PC hardware. This reduces costs aswell as the difficulty of accessing the data.Java may be continued to be directed by Sun in desktop applications,but the direction and utility in embedded applications will probablybe fractured. A number of companies now offer good Java VirtualMachine implementations.Internet: Key to the FutureThe Internet and its related technologies will be much more importantin the future. Sequencia uses Web-enabled documents where operatorscan use standard Internet browsers to monitor and record opera-©2001 by The Fairmont Press, Inc. All rights reserved.