A Note on Server and Target
Platforms (Operating Systems)
At present, WebSubmit is requires a UNIX system for its server and
assumes UNIX target systems. The dependencies on UNIX are mostly
incidental and minor, and arise from applying WebSubmit to an application
domain (high performance batch computing) that is strongly UNIX associated.
Neither the technology nor the implementation tools are UNIX-restricted.
One minor exception is that Expect is not yet available for Windows NT.
Thus some other support for binary file transfer would be required, e.g.,
ftp. Another exception of sorts is that Secure Shell (SSH) for
Windows is a commercial product. We use SSH to communicate between
the WebSubmit server and the target systems.
A Note on Client Platforms (Operating
Systems/Browsers)
Client systems may be UNIX or Windows. However, we have only
tested the software with the Netscape browsers (level 4 or higher).
In addition, at the moment we are using components of Netscape's LiveConnect
software in our target-side file browser. Compatibility with
a wider range of browsers is one of our goals for the next release.
Tcl/Tk
All of the WebSubmit libaries and modules are
written in Tcl (the Tool Command Language); the WebSubmit Configuration
Manager is the onl;y component of the package written in Tcl/Tk.
Tcl code is interpreted (not compiled), and hence a Tcl interpreter imust
be running on the WebSubmit server. The code is compatible with Tcl
interpreters at version 8.0 or higher. We are using verison 8.0.
Tcl/Tk is freeware and is available from the Scriptics web site:http://www.scriptics.com/software/8.0.html.
Your system may have a suitable version of Tcl/Tk installed already.
Expect (Tcl Extenmsion)
Expect is a Tcl extension written by Don Libes at NIST. It is
required to enable binary file transfers in the file transfer modules.
Expect-5.28 is included with the distribution in the extensions/expect-5.28
directory of the distribution and can be compiled using the Makefile.
Expect may already be installed on your system.
CGI Library (Tcl Extension)
CGI scripts in WebSubmit are written with the aid of Don Libes' excellent
cgi.tcl
library. Version of this software (0.7.5) is included with
the WebSubmit distribution in the extensions/cgi.tcl
directory. This is the most recent release that WebSubmit has been
tested with and past experience suggests that cgi.tcl
updates can be incompatible with previous versions.
Tcl-Bin (Tcl Extension)
TclBin is an extension to Tcl
that supports binary data objects and structures. This code is required
for authentication. It has been included in the WebSubmit distribution
in extensions/tclbin-1.2.
Web Server(s)
WebSubmit obvious requires a Web server and the security framework
in WebSubmit relies largely on (a) properly configured Web server(s).
This server must meet several requirements in order for the authentication
techniques used in WebSubmit to be functional. An insecure (HTTP)
server is used to allow unregistered users to gain access to a restricted
subset of the system, and also to register. A secure (HTTPS) server
is required for the primary WebSubmit applications. The requirements
for the HTTPS server are as follows:
Secure Shell (SSH) and Secure Copy
(SCP)
Remote command execution in WebSubmit is accomplished using the Secure
Shell (SSH) and Secure Copy (SCP) protocols. It is necessary to use
these
protocols to avoid potential security breaches due to IP or DNS spoofing.
SSH and SCP should be installed on the server and all target systems;
these pieces of software are available at http://www.cs.hut.fi/ssh/.
It is recommended that sites install SSH v1.2.26 or greater for interoperability
with the emerging SSH v2.x standard. Regretably, at the moment we
do not support SSH2. Which means you'll have to use an older version
of SSH if your system has SSH2 installed. SSH2 compatibility is pending
in the next release.