Network Working Group                                     James E. White
RFC #480                                                  SRI-ARC
NIC #14949                                                8 March 73


                     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    ]
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