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

Computer Networks and SecurityMany Internet sites require you to enter a user name and passwordin order to access information. You should never use your Windows NTlog-on password to sign on to a Web site. There is the chance that someonecould intercept the password and try it to log onto the system.Log-in and Registry SecurityThere is a Microsoft utility called TweakUL. This utility stores theuser name and password values in the Windows Registry in anunencrypted format. Hackers can access the Registry. If the system is setup for automatic log-on, you can still protect the log-in information byediting the permissions associated with the segment of the Registrywhere the information is automatically stored.You open the Windows NT registry Editor and choose Permissionsfrom the security dropdown menu. Then change the default permissionfor the Everyone group from Read to Special Access. Then, deselect theQuery Value check box. Now, when someone other than an administratortries to access the key, it will appear grayed out.Windows NT can clear the user name on the log-on screen. NT bydefault displays the name of the last person who logged onto the system.This can be a security threat, since a hacker may guess a user’spassword based on the account name or the log-in environment. You canclear the previous user name by adding a new string value calledDontDisplayLastUserNameSecurity is improved if there are only READ capabilities on theRegistry keys. The default setting is WRITE on some of the most importantkeys. These WRITE privileges allow a user to gain access to theserver. This can be prevented by changing the permissions on these keysto READ. Use the Registry Editor to change the security/permissions onthese keys.When a user starts an NT workstation, it automatically createssome shared resources. These include a share to the root directory of thehard drive that remains invisible during browsing. To prevent this automaticresource sharing you can edit the NT Registry settings.Windows NT holds data in swap files and temp files. In order tospeed access and improve performance, pages of data are swapped in©2001 by The Fairmont Press, Inc. All rights reserved.