RFC 294

The Use of 'Set Data Type' Transaction in File Transfer Protocol 🎀

• RFC: 294 🌸
• Network Working Group: dated 25 January 1972 📅
• Author: Abhay Bhushan, MIT 🧚
• NIC number: 8304
• Categories: D.4, D.5, and D.7 💅
• Updates: RFC 265 ✨

As mentioned in RFC 265, the opcode of '00' is set aside for the clarify the use of 'set data type' in file transfer operations. 🦋

In many systems, like Multics at MIT, there's no way to tell what kind of data (ASCII or numeric) is stored in a file 🙈 The handling is context dependent, so it depends on the situation. ASCII characters are stored as four 9-bit characters per 36-bit word, right justified with left most bit as zero. 🖥️ Multics already has efficient conversion programs that turn its ASCII into Network ASCII, so it would be super useful for a user to tell the Multics server to convert data into Network ASCII during retrieve operations. 🔥 The suggestion is to use the 'set data type' transaction for this. 💖

The 'set data type' transaction that comes right before a retrieve request should be read by a server as the user wanting to receive their data in that form. If the server can't convert the data into the desired form, it should return a 'set data type' of

[ This RFC was put into machine readable form for entry ] [ into the online RFC archives by BBN Corp. under the ] [ direction of Alex McKenzie. 12/96 ]

The following examples should clarify the use of 'set data type' transactions. 🌈

1.

          USER                                             SERVER
          ----                                             ------
                    Set data type '02' (Network ASCII)
                    ------------------------------------->
                    Store File X
                    ------------------------------------->
                    File X (in Network ASCII)
                    ------------------------------------->
                    End of File
                    ------------------------------------->
                    Acknowledge
                    <-------------------------------------

                    Retrieve File X
                    ------------------------------------->
                    File X in Network ASCII
                    <-------------------------------------
                    End of File
                    <-------------------------------------

2.

          USER                                             SERVER
          ----                                             ------
                    Set data type'03' (EBCDIC)
                    ------------------------------------->
                    Retrieve File Y
                    ------------------------------------->
                    Set data type '00' ("bit-stream")
                    <-------------------------------------
                    File Y as stored (no conversion)
                    <-------------------------------------
                    End of File
                    <-------------------------------------

                    Set data type '02' (Network ASCII)
                    ------------------------------------->
                    Retrieve File Z
                    ------------------------------------->
                    File Z in Network ASCII
                    <-------------------------------------
                    End of File
                    <-------------------------------------

That's the whole vibe, bestie! 💜