Microsoft Windows Server 2003 Unleashed (R2 Edition)

Windows Server 2003 released a series of significant improvements to the Terminal Services capabilities for thin client access. A client system working from a browser, a Windows terminal, or running the Remote Desktop Client software from a desktop system can access a centralized Terminal server to gain access to network resources. With Windows Server 2003, these same remote users can now do local drive and audio redirection, have local time zone support, choose the speed of connection to optimize the session performance, and take advantage of a service called Session Directory that provides better redundancy and recoverability in the event of a LAN, WAN, or Internet interruption.

Although all these new capabilities are highlighted here, they are covered in detail in Chapter 27, which addresses their planning, design, prototype testing, implementation, and optimization.

Local Drive and Audio Redirection

An update to Terminal Services in Windows Server 2003 is the ability for a remote client to access local hard drives as well as redirect the audio from a centralized Terminal server to a remote system. In the past, these capabilities required a relatively expensive add-in from Citrix Systems. Now that these capabilities are built into the core Windows Server 2003 Terminal Services, an organization can choose whether it wants to or needs to purchase the add-in.

Local Drive Redirection

Local drive redirection allows a remote user to log on to a centralized Terminal server to access network resources; however, if the user wants to retrieve or save files to a remote system, that system shows up as a drive letter on the session. The user can now drag and drop files between a remote system and the centralized server. The remote file access can include local C: hard drives, CD-ROM drives, floppy drives, or any other device that creates a drive letter for remote system access.

Audio Redirection

Audio redirection allows a remote user to log on to a centralized Terminal server and have sound redirected from the centralized system to the speaker of the remote client system. With organizations integrating voicemail and other audio-integrated tools and utilities into their daily business operations, having the ability to redirect audio to the remote system allows an organization to better support business tools using sound as part of the communication infrastructure.

Local Time Zone Support

With Windows Server 2003 Terminal Services, when a remote user logs on to a centralized Terminal server, the user now can work on either the default time zone on the server or choose the local time zone. This capability is important for organizations that have centralized servers used by employees across the country or around the world.

Earlier versions of Windows had support for only one time zone: the time zone of the Terminal server system. This meant that if the Terminal server was in California and a user from Georgia logged on to the Terminal server, all the individual's email messages or time stamps on file access were based on the Pacific time zone. With local time zone support in Windows Server 2003, now the remote user in Georgia can specify in her remote client access software to use the local time zone. Now when emails are sent, or when files are saved, the time stamp on the communications will be based on the Eastern time zone, where the user resides.

Windows Server 2003 supports all time zones and can have users from all time zones accessing the server at the same time.

Specifying Connection Type

Windows Server 2003 has added a new feature that enables remote users to specify the type of remote connection they have. Rather than having just a single server to remote client session configuration, remote users can specify that they are attaching to the Terminal server over a very slow modem connection, from a mid-speed broadband connection, from a very high-speed LAN connection, or from a customized configuration.

When a user specifies a slow modem connection session, the Terminal server system automatically optimizes server-to-client communications by not running functions that take up session performance such as complicated user backgrounds on a screen desktop. It also optimizes mouse and keyboard controls and disables Windows themes and unnecessary screen animation to provide more communication bandwidth to remote application access functions.

When a user specifies a mid-speed broadband or a LAN connection, more of the features are enabled so that backgrounds, themes, animation, and menu variations are transferred just as if the user were sitting at a desktop at the office.

This minor user-defined optimization enables remote users to improve their session connection and thus their user experience based on the speed of their connection.

Session Directory

New to Windows Server 2003 is a technology called Session Directory that allows remote users to reconnect to the exact same session that they were running before a temporary Internet, dial-up, or WAN connection failure caused a disconnection. This automatic reconnection has always worked fine if the organization has only one Terminal server; however, when an organization had multiple Terminal servers, there was no way for the remote client session to know which of the potential 32 servers to reconnect the user to.

Session Directory now runs on a separate system and keeps track of all user-connected sessions. When a user attempts to log on to one of the servers in a Terminal server load-balanced environment, Session Directory checks whether the user had previously connected to a session that might still be active. If it finds an active session, it reconnects the user to that session, thus restoring the user to exactly the place he left off before being terminated.

Session reconnection requires the Terminal server policy to keep sessions active for a period of time after unexpected disconnection. Best practices allow a remote user up to 10 minutes to reconnect to a dropped connection to re-establish his session right where he left off. However, after 10 minutes, a dropped connection is flushed from the Terminal server to free up server memory, processing capacity, and a remote session software license with the assumption that the remote user might not have been disconnected accidentally, but rather that the user just forgot to log out of the system when he was done. Session reconnection provides a variety of features and options that are addressed in detail in Chapter 27.