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Network Working Group                                  Abhay K. BhushanRFC # 463                                              MIT-DMCGNIC # 14573                                            February 21, 1973FTP Comments and Response toRFC 430    Most of the comments inRFC 430 by Bob Braden are useful suggestionswhich should be included in the forthcoming official FTP specification.This RFC represents my response to Braden's comments and other views.These comments should be useful for the FTP meeting on March 16 at BBN(announcement warning AAM NIC #14417). The results of the FTP subgroupmeeting held at BBN on January 25 will be published inRFC 4541 (arepublished?).SPECIFIC RESPONSES TORFC 430.    Item A1 - I will let Bob Braden handle the "print file" issues (the    "still" should be removed).    Item A2 - I agree that concessions are undesirable and should be    removed unless people cannot "live" without them.    Item A3 - I strongly support "bit flag coding" for descriptors.    Other definition improvement suggestions are ok too.    Item A4 - The diagram was useful. An alternate one is given on page    17 ofRFC 454. I prefer the latter.    Item A5 -  The FTP may not be privileged enough to alter passwords    in many Host systems (e.g. Multics). I know that CCN allows changing    passwords on-line. We can define a format for changing passwords in    the pass command, but I don't think we can require that all servers    allow password changing. This is a minor problem that can be easily    solved.    Item A6 - Yes, the comment that TYPE should be before BYTE was for    bad implementations. The server should reject data transfer    parameters only when the data transfer command is received. The    order of the parameter-change commands is not important.    Item A7 - I do agree that NCP's should be fixed.  A 255 (socket    number) reply should be required at a specific time, and NCP's    should be able to provide it (this also permits the proposed GSOC    command). Let us find out at next meeting if there is anyone who    cannot live with this new requirement.Bhushan                                                         [Page 1]

RFC 463           FTP Comments and Response toRFC 430     February 1973    Item A8 - Yes.    Item B - There are at least two ways to solve the FTP parameter    encoding problem presented by Bob Braden. One is to allow multiple    letter in the TYPE command as suggested by Bob and the other is to    have a new command such as FORM (which could be P or U). Other    solutions are equally acceptable to me.    Item C - Our emphasis should be on working protocol as well as    elegance. I like the proposed GSOC command over the listen.  In fact    GSOC can be used for all data connection security checking. The 255    reply should be sent with GSOC only, and the server should use only    those sockets for data connection.    Item D - We need more discussion on the issue of site dependent FTP    parameters. I will put it on the agenda for the forthcoming FTP    meeting.FURTHER COMMENTS    1. The command-reply sequence needs to be tightened in both    specification and implementations to allow convenient use of FTP by    programs or "automatons".    2. A 300 reply greeting upon first connecting to the FTP server    should be required and not optional. This avoids the programs having    to wait an arbitrary time for such a greeting before issuing    commands. Commands may only be sent after the 300 reply is received    from the server.    3.RFC 454 needs a discussion of transfer between two FTP servers    arranged by the user via the LSTN or GSOC commands.    4. Perhaps we should allow specification of data transfer parameters    in a single command line (for reasons of efficiency).  A suggested    format is to have <SP> separate the parameters bunched together in a    single line (requiring only a single reply).  Consider the following    sequences:            STRU F TYPE I BYTE 36 MODE S <CR><LF>            reply - 200 OK    5. Further discussion of MAIL and MAIL.file commands seems    necessary. Perhaps we will get some useful input from the MAIL    meeting at SRI on February 23, The following issues seem    particularly relevant to me:        a) Allowing mail to multiple users. It should be required that    FTP servers allow this.Bhushan                                                         [Page 2]

RFC 463           FTP Comments and Response toRFC 430     February 1973        b) Using NIC idents. FTP servers should accept some standard    form of user name. This could be NIC idents or last name with    optional use of initials.        c) Uniform conventions for who the mail is from, day, time,    etc., and how the mail is delivered to user. The mail usually gets    tagged twice or sometimes not tagged at all.  Perhaps we need a    different mechanism for indicating who the mail is from than    provided by the USER command.        d) handling bulk or junk mail (particularly the NIC documents    that may be sent on-line by the NIC). Perhaps mail.file should put a    file in user's directory and notify him of the same. The user does    not see all the junk on his console but can print the file on a    printer and read that class of mail at his leisure.       [ 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 ]Bhushan                                                         [Page 3]