Anonymous FTP

The FTP Archive

The department maintains an anonymous FTP site for the purpose of disseminating Brown software and other documents. The URL is:

	ftp://ftp.cs.brown.edu/

There are four sections of the archive, the public section (/pub), the user section (/u), the incoming section (/incoming) and the guest account section (not visible).

The Public And User Sections

The public section is for posting software and other documents that are meant to reach a broad audience. The user section is for posting materials meant for a limited audience, but without any limitations on who may access them.

The public and user sections of the ftp archive are maintained on the local filesystem in /u/ftp, and copied to the ftp server machine nightly (or with the command ftpupdate, see below). These sections of the archive can be modified directly at /u/ftp/pub and /u/ftp/u.

No uploads are permitted to either of these sections, and there are no limitations on who may download from them.

The Incoming Section

Files may not be uploaded to the incoming section itself, but only to subdirectories of it. Local users may create incoming subdirectories in /u/ftp/incoming. These are removed automatically after they have not been modified for 3 days.

Directories should be created world writable. For example:

% mkdir -m 01777 /u/ftp/incoming/jsb

Downloads are not permitted from the incoming section, only uploads. Remote users cannot create directories via ftp.

Instruct remote users to connect, via anonymous ftp, to (following the above example):

ftp.cs.brown.edu:/incoming/jsb

to upload files.

Local users access uploaded files directly using the filesystem. Uploaded files can be read and removed by the person who created the subdirectory.

FTP Guest Accounts

For non-public file tranfers, where privacy is a concern, you may want an FTP guest account. This requires the remote user to type a password to login, and places them in a part of the archive that is inaccessible by anonymous ftp. The password and transfer are unencrypted, so the security this provides is minimal. Like the incoming section, the guest section of the ftp archive is mounted locally at /u/ftp/guest. Guest account subdirectories are owned by the people who requested them, so they can add or remove files directly.

Contact the ftp administrator for an ftp guest account.

Ftpupdate

The ftpupdate(1) command copies files and directories in the public and user sections of the ftp archive from the local filesystem to the ftp server machine. It is run nightly on the whole archive.

You must have owner or group permissions to the files or directories you want to update.

Backups

Only the public and user sections of the archive are backed up. The incoming and guest sections are remotely mounted from the ftp server machine itself, so they do not benefit from the department's nightly backup regimen.

Legal Issues

Anything you put on our ftp archive is immediately available to the entire world. Many things on our systems may not be distributed beyond the department, the university or, in some cases, the country. The constraints are license agreements, copyrights, and US export laws.

So you must be very careful about what you put up for ftp. In general, if you wrote code here at Brown, it is probably at least partly owned by the University, and so it must have a Department copyright notice on it. Other software runs the gamut from freely redistributable to proprietary trade secrets - you can't always tell without asking - so ask first.

Most of these encumbrances do not apply to articles or papers. In general, they may be distributed freely. An exception is journal articles, which may become the property of the journal.

More Information

For help with these and other ftp needs, contact the ftp administrator.