sscc

SSCC News for December 2001

Inside this issue...

Telnet to be Disabled in January
Status of Problems Accessing UNIX Disk Shares from NT/2000
Web-based Tools for Remote Users
New Publications available On-line


Telnet to be Disabled in January

Beginning Wednesday, January 2, 2002, SSCC will be disabling external telnet access to SSCC UNIX computers. Telnet is a clear-text protocol, which means any data that is passed along the data stream is unencrypted (including passwords). This allows any malicious person who can intercept ("sniff") the data access to a user's password, and therefore access to their account. We are replacing telnet with a protocol called SSH. SSH is completely encrypted, so anyone sniffing the data stream will only see garbage.

DoIT provides a PC SSH client as part of Wiscworld called SecureCRT. This software can be downloaded from DoIT's web page. A word of caution, you must specify SSH as the connection protocol when you set up your new sessions within SecureCRT. Otherwise, it uses the telnet protocol. Note that DoIT's download web page is only accessible from UW network (IP) addresses. If you happen to be traveling, or get your Internet service from some other source than the UW, we recommend a freeware PC SSH client called PuTTY.

There is also a Mac SSH client included in Wiscworld called NiftyTelnet. It is free, and can be downloaded from the above link no matter where you are.

Telnet access from the local network (which consists mostly of computers in the Social Science building) will still be allowed, because both the older NCD X-terminals and the newer Winterms only have Telnet clients, and can't provide SSH connectivity.

See SSCC publication "Connecting to SSCC Linux Computers Using SSH" for more information.


Status of Problems Accessing UNIX Disk Shares from NT/2000

As many graduate students are painfully aware, we have recently been experiencing intermittent problems with SAMBA, the software we use to provide UNIX disk access from Windows-based PCs (including Windows Terminal Servers). Our plan was to upgrade SAMBA and staff testing indicated this would fix the problem. But, when we put the upgrade into production, the problems only got worse, especially for Wincenter and Winstat users. There appears to be a synching problem which means we need to reboot all the servers when upgrading SAMBA. Because this is so disruptive, we are going to wait and try the upgrade again during the Holiday break when fewer people are around. We will make an announcement about the down time in advance.


Web-based Tools for Remote Users

We now have a link on SSCC's web site where remote users can find web-based tools for reading E-mail (Squirrel), accessing SSCC's Windows Terminal Servers (Wincenters and Winstats), and logging on to UNIX and Linux computers (MindTerm).

All of these applications will run directly in your web browser with no need to install anything. This requires a fairly modern browser, and you can only connect to Windows Terminal Servers with Internet Explorer. Note that MindTerm connects to GUY, but once there you can connect to any other server by typing ssh servername (for example ssh norman).

The main value of these programs is that you can use them anywhere, however you will find that they simply don't work as well as software actually installed on your computer. We recommend using Eudora or Pine for E-mail, the Citrix ICA client for connecting to Windows Terminal Servers, and SecureCRT for connecting to UNIX and Linux servers. All are available without charge to UW faculty, staff, and students. Consider the web versions a last resort.


New Publications available On-line

Here's some other new information available on SSCC web site:


Go to previous editions of SSCC News.
Go to the SSCC Home Page.

© 2001 University of Wisconsin Social Science Computing Cooperative