Ataman Provides Telnet and Rlogin Services for Windows NT

Ataman Provides Telnet and Rlogin Services for Windows NT
Ataman TCP Remote Logon Services release 1.7 contains server implementations of the Internet TCP Telnet, Rlogin, and Rexec protocols. These programs install and run as services on your Windows NT Server or Windows NT Workstation.

Ataman Remote Services adheres to established protocol definitions for the Telnetd and Rlogind services as established in Internet documents RFC 854 and RFC 1282. With the appropriate client, any machine can remotely log on to an NT Server or NT Workstation. Remote users log on using the same user-names and passwords and are subject to the same security restraints as local users. If the remote client supports ANSI, VT100, VT220, Zterms, or Xterm terminal emulation, the remote user may run full-screen console applications, such as text editors.

Installation
Installation is done from the command line. You must have Administrator or Domain Administrator privileges.You create a local directory for the Ataman Remote Services executables; their permissions must be set to read and execute by the system account and those user accounts that will log in remotely. To start the services, you issue a series of commands, install start, where service_name is Telnetd, Rlogind, or Rexecd. Then you need to grant permission for users to log on as a service. If you decide not to register, issue the command stop remove from the command line for each service you want to remove. This action will update the Registry, but you need to remove the actual files yourself.

Ease of Use
From the server side, once you install it, you're done except for adding new users now and then. The real test comes when somebody logs on.

Ataman Remote Services functions the same as most Telnetd servers--you must have a valid user name and password. Ataman Remote Logon supports local as well as domain logins. If you have a valid user name in the same domain that the machine is in, you can use your domain user name. Various rules involving backslashes enable you to manage non-NT clients the same as you do NT clients, adding security and simplicity to your administrative chores.

Normal Rexecd and Rlogind servers have a 16-character limit on user names. Ataman Remote Services doesn't enforce this limit, however, to accommodate NT's sometimes lengthy user IDs.

Features
Once a connection has been established to the remote machine, you can choose whether to use advanced features. If your client supports VT100, VT220, ANSI, Xterm, or Zterms, you can use the advanced screen addressing features rather than standard line-oriented text.

If you don't use the advanced features, you can still log in, but no full-screen applications can run. The main reason to choose advanced mode is its ability to run full-screen console programs. Your SPARCstation still won't run Word, but it is easier than using ed.

There are many programs that don't work correctly under Ataman Remote Services; for example, EDIT.EXE doesn't work.

Ataman Software provides ports of many public-domain UNIX programs that work under Ataman Remote Services. These programs are available from Ataman's FTP site. If you connect via a slow link, you may not want to use full-screen applications because they send a lot of data, a slow process over this kind of connection. However, you can still connect and use simple mode.

Simple mode allows you to use most console-mode programs that read from standard input and write to standard output. Limited command-line editing is available in simple mode.

A Good Graft
Ataman Remote Services is a good implementation of the Telnetd and Rlogind services. It is not the preferred method for connecting NT clients; however, if you routinely interact with clients other than NT's, it is an excellent way of providing connectivity. NT doesn't provide these services, and Ataman Software has done an admirable job of grafting them onto it. There is a price, however.

Brian Sturgill, President of Ataman Software, explains. "Windows NT provides no way for a parent process to know about the children of its child processes. Further, no method of cleanly killing another process is provided. (There is a kill provided, but it does not notify DLLs that are attached to the killed process of an exit, potentially leaving dead data inside them.) The net effect is that it is not possible for the Telnetd, Rlogind, and Rexecd services to clean up. Remote users [must] be aware that they should always log out by exiting any applications they are running and typing the exit command. Over time, "orphaned" processes from remote users will likely [occupy] an unacceptable number of system resources. At this time, the only known solution is to reboot the system. For systems that are used heavily by remote users, it may be advisable to schedule reboots on a regular basis." [Editor's note: Sturgill assures us that Windows NT 3.51 fixes these problems.]

Another problem is clear-text passwords. If you have been using Telnet, Rlogin, or Rexec on a UNIX system, you have been transmitting your account information over the network unencrypted. Ataman Remote Services adheres to these protocol standards and suffers from the same limitations. As with all remote logons, you should assess the risk of having your account information intercepted. If you need to provide Telnet access, then you need Ataman Remote Services.

Availability
Ataman TCP Remote Login Services is available in a variety of places. The archive name is ATRLS17.ZIP. You can download the file from the Web site at http://www.bhs.com/application.center/ or FTP at rmii.compub2ataman; from CompuServe at GO WINSHARE library Win NT Utils/Apps; or directly from the company.