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Network Working Group                                     Alex McKenzieRequest for Comments #180                                 BBNNIC #7123                                                 25 June 1971Categories: D.7, G.3Updates: noneObsoletes: noneFile System QuestionnaireAs noted in RFC #164 (page 35), a subcommittee of the NWG, under thechairmanship of Abhay Bhushan, is currently generating proposals for a"data transfer protocol" and a "file transfer protocol".The subcommittee has decided that the file transfer protocol shouldprovide standard methods for requesting the transfer of a file butshould not, at this time, attempt to standardize file namingconventions, access control conventions, and the like.  Thus a userwho is, for example, trying to store a file on a remote Host will berequired to use the file naming conventions appropriate to the remoteHost.Given the above point of view, it becomes imperative for users to havesome source of information about Host file conventions.  Suchinformation, once compiled, will also serve as input to possiblestandardization efforts of the file transfer subcommittee.  For thisreason Abhay has asked me to solicit information on file conventionsfrom the Host organizations.  What follows is a description of thekinds of information of interest.  I am well aware of the fact thatmany of you are tired of writing system descriptions; Xerox copies ofshort sections of your local documentation are fine if the result iscomplete and comprehensible.  (In the case that your Host will neverpermit network use of your file system, a note to that effect would besufficient.)                         Information Requested1.  File naming conventions - We (loosely) define a pathname to be    the data string which must be input to the file system by a user    (a network user if your system makes a distinction between local    and network users) in order to identify a file.  We are interested    in syntax, semantics, and defaults.  Typical components of pathnames    are:         - "device" fields         - user names         - version numbers         - index names         - punctuation marks                                                                [Page 1]

Common types of defaults are:         - device is disk         - version number is largest in system    For hierarchical file structures, descriptions may be fairly    complex, but with lots of defaults; in such cases an illustration    of a "normal" pathname might be helpful.2.  Access control mechanisms - Access control mechanisms range from    simply knowledge of a file's pathname to elaborate hierarchies    of group-project-task-username membership with passwords and    separate controls for reading and writing.  There are two    aspects of the access control mechanism which are of interest:    a.  A description of what inputs the user should give the file        system, both at the time of file creation and at the time of        retrieval, in order to define the permitted modes of access        and to gain access.  What are the syntax and semantics of        these inputs?    b.  A description of the ways in which the access control        mechanism is designed to help (or hinder) the sharing of        files.  For example, may two users "simultaniously" update a        given file?  May the creator of the file define a set of        authorized users to the file system (and how)?  Is it possible        to define different access controls for various subunits of a        given file?3.  Directories - Many systems maintain file directories which are    designed to be helpful to the user.  A directory might, for    example, provide a list of all files created by a particular    individual, along with some information regarding file size,    file structure, access controls, etc.  In general, such systems    allow the user to input a pathname and retrieve the directory to    which that pathname refers.  Aspects of the directory structure of    interest are:    a.  What are the syntax and semantics of a directory pathname?    b.  What use is a directory, i.e., what type of information        does the directory contain?    c.  What access controls are used for access to the directories?        For example, must a user supply a password in order to        retrieve a directory, and is this password typically the same        as the password he would use to retrieve a file listed in that        directory.                                                                [Page 2]

4.  Commands and functions of the file system - A general description    of what the file system is designed to do would be useful.  For    example, the system might simply accept an entire file and store    it sequentially on a tape; with the only mode of retrieval being    to retrieve the entire file.  On the other hand, the system might    provide the ability to access any "subfield" with a unique    pathname.  Perhaps there is the ability to restructure a file,    change the access control, delete all the fields associated with a    directory, etc.  We realize that this aspect of the file system    begins to overlap the area of "data management", which is the    responsibility of another subcommittee; therefore, use your    judgement as to what functions are an intrinsic aspect of the    file-handling system and which are aspects of "data-management".5.  Internal representation and I/O modes - The remote user of a file    system will normally be interested in internal representation of    data only insofar as that representation of data is reflected in    the I/O interface between the file system and the network.  For    example, if all of the file system's I/O is in 8-bit ASCII    characters, then the user is unlikely to care if they are stored    in ASCII, EBCDIC, or some other form.  However, if an alternate    transmission mode is available it may be useful; for example,    two PDP-10's, both of which store 5 characters and one "filler"    bit per word, might find it advantageous to transfer information    in this mode rather than converting between internal representation    and 8-bit ASCII for each character.  Other information on internal    representation which would be of interest to the user might    include (if applicable):         - range of numeric data permitted         - maximum text string lengths         - whether the user must indicate "record" boundaries on input         - what "logical structure" information the user may specify           for a new file, and what he must specify         - whether the user must specify the file size before beginning           input, and how he does it6.  Undoubtedly, there will be aspects of each file system which don't    fit neatly into the categories above, but which users will find    important or essantial in using the system.  These should be    identified and described if possible.    Please address responses to this questionnaire to:               Alex McKenzie               Bolt Beranek and Newman Inc.               50 Moulton Street               Cambridge, Massachusetts 02138                                                                [Page 3]

If the questions above are confusing, don't hesitate to call me forclarification at (617) 491-1850 ext. 441.  I will issue another RFCsummarizing the responses after I have received a significant numberof them.       [ This RFC was put into machine readable form for entry ]         [ into the online RFC archives by Stefan Hinker 6/97 ]                                                                [Page 4]