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The FTPdig Project

The FTPdig Project

Sternberg Astronomical Institute, Moscow University

What is FTPdig?

The idea behind this project is rather simple: using CGI scripts as processing tools and WWW browser as user interface, display the structure and content of typical anonymous FTP server in a convenient, easily navigated form. One can list the features typical archive user needs:

The need for this kind of interface to old-fashioned anonymous FTP service is great which is demonstrated by popularity of such services. Historically, probably the first widely known project of this kind was LEO (Link Everything Online); during last year, FTP search has gained a lot of attention. Several services of smaller scale are already operational or under development. However, both LEO and FTP search have their limitations: LEO is only serving its own ftp server (although very large one), FTP search is mostly oriented towards search with other functions being primitive or missing.

Goals and perspectives

The current goal of FTPdig project is to build University-wide network of ftp servers unified by the same interface and database. In other words, one can access several anonymous ftp servers as if it was single (and very large!) one, with all features mentioned in What is FTPdig available.

The project will be greatly helped by recent deploying of campus-wide fiberoptic link in Moscow University. This allows to distribute contents among many independent servers, interconnected by high-bandwidth link, just how it is currently done. Therefore no major reconstruction of anonymous ftp services is needed. The FTPdig interface and database can be mirrored on any local server, thus giving virtual instant access to all servers at once from any location. However, some services (like examining contents of archives) will still require access to original sites where actual files are kept.

In perspective, the project can be extended to cover the entire network of ftp servers in Russia. Architecture of existing implementation does not scale well above 1,000,000 files total. Expansion might require significant rewrite of underlying algorithms.

Technical background

Every new method has its own advantages and drawbacks. Let's compare traditional approach (sophisticated FTP client software like NFTP) and CGI-based WWW interface like FTPdig.

The advantages of WWW interface are:

The disadvantages are:

The model of FTPdig distributed service has been

You might want to read also implementation notes on File Juggler, current incarnation of FTPdig project. Performance problems and limitation of current design are discussed there.

Current status and implementation

With rapid growth of SAI ftp archives, it has become a necessity to have a convenient search and navigation interface for them. Such interface was implemented by Dr. Sergey Ayukov, research fellow at Sternberg Astronomical Institute of Moscow University. The software was named "File Juggler"; it is considered the first stage of FTPdig Project.

File Juggler Version 1.0 is now installed on two ftp servers at Sternberg Astronomical Institute, Moscow University:

  1. Crydee.sai.msu.ru archive (mostly OS/2 software, recreation and leisure)
  2. SAI FTP archive (lots of free material available on the Internet, including astronomy, Unix software, Linux etc.)
The source code is not available yet for general distribution.

Version 1.0 can only work with one ftp site at a time (on which it is installed). Next version which will provide interface to several ftp servers simultaneously is under development.

File Juggler uses cgic library, copyright 1996 by Thomas Boutell.


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