Host-Dependent FTP Parameters

This memo is in response to (and support of) one of the points raised by Bob Braden (RTB) of UCLA-CCN in RFC #430, "COMMENTS ON FILE TRANSFER PROTOCOL" (see -- 13299,), namely that raised in Section D., "Site- Dependent FTP Parameters".

The NIC has been confronted with similar problems (and tentatively decided upon similar solutions) in designing mechanisms which would enable a user to use FTP to retrieve from the NIC, in sequential form, a VIEW of some portion for an NLS tree-structured file.

To be done without modification to FTP, this task requires the user to communicate information -- a filename, a statement address, viewspecs, and the name of a conversion algorithm -- to SRI-ARC's server FTP process in a manner that is transparent to the user's user FTP process.

We currently intend to require the user to embed this information in the pathname of FTP's STOR and RETR commands by appending to a standard TENEX filename, a field of the form:

    ;x <program> [ / <parameters> ]

where <program> identifies an arbitrary program to be dispatched by SRI-ARC's server FTP process, with a pointer to the file being stored or retrieved as an argument. <parameters> is optional and, if present, is also passed to the program.

To store and retrieve NLS files in sequential form, we will require that

<program> be 'NLS' and <parameters> be of the form.

    [ T: <conversion-algorithm> ] [ S: <statement address> ] [ V:
    <viewspecs> ]

where each of the three items is optional, and any that appear are

separated by commas.

       [ This RFC was put into machine readable form for entry ]
       [ into the online RFC archives by Alex McKenzie with    ]
       [ support from GTE, formerly BBN Corp.             9/99 ]