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Telnet Hits the Enterprise, and It's Not Just for Geeks Anymore

By ServerWatch Staff (Send Email)
Posted Dec 8, 1999


With some features not expected from a telnet server and robust performance not usually expected from a Windows-NT-based product, Georgia SoftWorks Windows NT Telnet Server is an excellent choice for enterprises looking for a thin-client solution without incurring the overhead of a new operating system or Java technology.

Telnet is staging a comeback of sorts, despite being left for dead on the road of failed protocols (joining Gopher and POP2) by some Internet "experts" and dissed by Microsoft in favor of the preferred RAS method of supporting remote users. Proponents argue that telnet is a more robust and mature technology when it comes to accomplishing the goals of thin-client technology. As a result, telnet servers like Georgia SoftWorks Windows NT Telnet Server are evaluated on different criteria than in the past, when "telnet" meant a tool used by system administrators and expert users to log remotely onto a system. Today's telnet servers might also need to support a larger number of general users who have higher expectations for their telnet sessions.

With some features not expected from a telnet server and robust performance not usually expected from a Windows-NT-based product, Georgia SoftWorks Windows NT Telnet Server is an excellent choice for enterprises looking for a thin-client solution without incurring the overhead of a new operating system or Java technology

The newer features in Georgia SoftWorks Windows NT Telnet Server make sense under these new rules. The first of these features is automatic reconnection for failed sessions. When used, this allows a user to reconnect to a telnet session after a client or link failure and resume the session as if nothing went wrong. Essentially, this means if a user experiences a system crash or a dropped Internet connection, Georgia SoftWorks Windows NT Telnet Server will maintain the session for a set period of time (as determined by the Windows NT Telnet Server system administrator) before completely closing down the telnet session. Normally, a system administrator would want a session to end immediately after a failed session — and this is the default in Georgia SoftWorks Windows NT Telnet Server. but having the option of waiting for a user to reconnect to a session is a useful one. A remote user can automatically reconnect to a session in two ways.

  • The server can detect the incoming IP address and determine whether the user at that address has a suspended session
  • A group of users allowed to reconnect to suspended sessions is set up

The other major factor when considering telnet in a thin-client environment is security. In the past, telnet was considered a fairly unsecure protocol. To address this, Georgia SoftWorks Telnet Sever for Windows NT offers 128-bit complete Data Stream Encryption. Thus, entire sessions can be encrypted and secured. (For this to be implemented, the remote user must be using the Georgia SoftWorks Telnet Client, which is included free of charge with Georgia SoftWorks Telnet Sever for Windows NT.) This isn't a tool to be used by every connected user, unless the enterprise is employing a superfast server with a ton of RAM and a dedicated board for handling encryption, as processing the encryption algorithms puts great strain on a server. Georgia SoftWorks claims data stream encryption can be enabled with undetectable performance loss, but in our testing we saw a small hit on performance when we enabled this feature for a single user. Data stream encryption can be enabled on a per-user or global basis, as well as applied to only log-ins (which would protect user IDs and passwords). In addition, the security mechanisms in Georgia SoftWorks Telnet Sever for Windows NT are integrated with the Windows NT security tools, so log-ins can be restricted or enabled on the basis of user ID or IP address. Expired password handling in Georgia SoftWorks Telnet Sever for Windows NT is different from what is usually found in the Windows NT telnet world: When a user enters an expired password, he or she is prompted for a new password as if connecting locally to a Windows NT server.

On a Windows NT 4.0 server with 128 MB of RAM and a 13-GB hard drive, we tested Georgia SoftWorks Windows NT Telnet Server with a moderate level of traffic. We simulated 15 simultaneous log-ins and tried to generate a decent level of traffic. A look at the Windows NT Performance Monitor showed an impact on the system load, but not enough to come remotely close to impacting system stability or even to lead us to believe we couldn't use Georgia SoftWorks Windows NT Telnet Server to support several hundred telnet users. Earlier testing by the National Software Testing Laboratories for Software Digest on a previous version of Georgia SoftWorks Windows NT Telnet Server confirms the robust nature of the product when supporting a high number of users.

Other Georgia SoftWorks Windows NT Telnet Server features are noteworthy in the Windows NT telnet world as well. Session shadowing allows a remote user to watch an ongoing session and enter keystrokes (as opposed to pure session monitoring, where the third user can view a session but not participate in it). The DOSBoss feature — which we used when we tested system performance — optimizes DOS applications running under Windows NT. This is a necessary feature in a high-performance environment, as DOS applications running under Windows NT are notorious for poor performance. Georgia SoftWorks Windows NT Telnet Server supports connections from any RFC-854-compliant telnet client, which pretty much covers basic clients used on Unix, Macintosh, Linux, Windows (95, 98, NT, and CE), and other operating systems. It will also support emulation for a wide variety of terminals, including DEC VT-100, DEC VT-220/320/420, SCO Console, AT386, Wyse 50/60, IBM 3101, and IBM 3151.

With 128-bit encryption and autoreconnect of dropped sessions, Georgia SoftWorks Windows NT Telnet Server is one of the leading telnet tools for those enterprises that want to employ telnet in thin-client situations.

Pros: Autoreconnect for failed sessions 7 Optional 128-bit data stream encryption 7 Very affordable 7 Optimization of DOS applications running under Windows NT 7 Full integration with Windows NT security tools

Cons: Developers may be too optimistic about the performance degradation when using full-session encryption 7 No Unix version

New in v6.17.0001: Automatic log-on for third-party clients; color re-mapping available for all clients; new Java Applet parameters allow flexible display options; new Java Applet parameter specifies the host to connect to; new file transfer capability when going from server to client; can disable the mouse during telnet sessions; log-in time performance improvement; system administrator can generate reports based on telnet log information; true client-side printing; Release Notes
Upgrade Meter: 3

New in v6.19.0001: Automatic Reconnect no longer performs an invalid reconnect when the AUTO_BY_USER_AND_IP option is chosen; added an optional floating license hardware key; GS_GET utility added to the file transfer options, completing both directions; Release Notes
Upgrade Meter: 2

New in v6.20.0000: Automatic log-on feature implemented for GSW Client; log-on limitations via telnet are available (this is an especially useful feature for ASP customers); IP Addresses can be specified as ranges and wildcards can be used; Release Notes
Upgrade Meter: 2

New in v6.21.0002: A new utility, gs_exec, that enables commands to be executed on the client from within a telnet session is included in the telnet server installation directory; Release Notes
Upgrade Meter: 2

New in v6.22.0001: Modifications made so server can better interface with Symbols Wavelink Telnet Client Protocol; defect resolution to improve slow connect times that occurred in certain cases on high-use systems; Release Notes
Upgrade Meter: 1

New in v6.23.0006: Support for printing labels on portable printers using SAPConsole; character translation table for third-party Telnet clients; configurable terminal initialization string support; support for the default F5 key mapping of Symbol RF Terminals; support for the Georgia SoftWorks Rocket Terminal Engine; Release Notes
Upgrade Meter: 2

New in v6.24.0002: Increased the capacity to provide an even greater number of sessions with minimal impact to the operating system; internal interface enhancements with Rocket Terminal Engine; Release Notes
Upgrade Meter: 1

New in v6.26.0003: Automatic upgrade of the GSW Telnet Client to the current version on connection; -z command line parameter for GSW Client to disable Automatic Update; Release Notes
Upgrade Meter: 2

Version Reviewed: 6.01 Last Updated:6/24/02
Date of Original Review: 12/8/99 Reviewed by: Kevin Reichard

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