doc: Add RFC documents

1 files changed, 227 insertions, 0 deletions

diff --git a/doc/rfc/rfc860.txt b/doc/rfc/rfc860.txt
new file mode 100644
index 0000000..2a2f11a
--- /dev/null
+++ b/doc/rfc/rfc860.txt
@@ -0,0 +1,227 @@
+
+Network Working Group                                          J. Postel
+Request for Comments: 860                                    J. Reynolds
+                                                                     ISI
+Obsoletes: NIC 16238                                            May 1983
+
+                       TELNET TIMING MARK OPTION
+
+
+This RFC specifies a standard for the ARPA community.  Hosts on the ARPA
+Internet are expected to adopt and implement this standard.
+
+1.  Command Name and Code
+
+   TIMING-MARK          6
+
+2.  Command Meanings
+
+   IAC DO TIMING-MARK
+
+      The sender of this command REQUESTS that the receiver of this
+      command return a WILL TIMING-MARK in the data stream at the
+      "appropriate place" as defined in section 4 below.
+
+   IAC WILL TIMING-MARK
+
+      The sender of this command ASSURES the receiver of this command
+      that it is inserted in the data stream at the "appropriate place"
+      to insure synchronization with a DO TIMING-MARK transmitted by the
+      receiver of this command.
+
+   IAC WON'T TIMING-MARK
+
+      The sender of this command REFUSES to insure that this command is
+      inserted in the data stream at the "appropriate place" to insure
+      synchronization.
+
+   IAC DON'T TIMING-MARK
+
+      The sender of this command notifies the receiver of this command
+      that a WILL TIMING-MARK (previously transmitted by the receiver of
+      this command) has been IGNORED.
+
+3.  Default
+
+   WON'T TIMING-MARK, DON'T TIMING-MARK
+
+      i.e., No explicit attempt is made to synchronize the activities at
+      the two ends of the TELNET connection.
+
+4.  Motivation for the Option
+
+
+
+Postel & Reynolds                                               [Page 1]
+
+
+
+RFC 860                                                         May 1983
+
+
+   It is sometimes useful for a user or process at one end of a TELNET
+   connection to be sure that previously transmitted data has been
+   completely processed, printed, discarded, or otherwise disposed of.
+   This option provides a mechanism for doing this.  In addition, even
+   if the option request (DO TIMING-MARK) is refused (by WON'T
+   TIMING-MARK) the requester is at least assured that the refuser has
+   received (if not processed) all previous data.
+
+   As an example of a particular application, imagine a TELNET
+   connection between a physically full duplex terminal and a "full
+   duplex" server system which permits the user to "type ahead" while
+   the server is processing previous user input.  Suppose that both
+   sides have agreed to Suppress Go Ahead and that the server has agreed
+   to provide echoes.  The server now discovers a command which it
+   cannot parse, perhaps because of a user typing error.  It would like
+   to throw away all of the user's "type-ahead" (since failure of the
+   parsing of one command is likely to lead to incorrect results if
+   subsequent commands are executed), send the user an error message,
+   and resume interpretation of commands which the user typed after
+   seeing the error message.  If the user were local, the system would
+   be able to discard the buffered input; but input may be buffered in
+   the user's host or elsewhere.  Therefore, the server might send a DO
+   TIMING-MARK and hope to receive a WILL TIMING-MARK from the user at
+   the "appropriate place" in the data stream.
+
+   The "appropriate place", therefore (in absence of other information)
+   is clearly just before the first character which the user typed after
+   seeing the error message.  That is, it should appear that the timing
+   mark was "printed" on the user's terminal and that, in response, the
+   user typed an answering timing mark.
+
+   Next, suppose that the user in the example above realized that he had
+   misspelled a command, realized that the server would send a DO
+   TIMING-MARK, and wanted to start "typing ahead" again without waiting
+   for this to occur.  He might then instruct his own system to send a
+   WILL TIMING-MARK to the server and then begin "typing ahead" again.
+   (Implementers should remember that the user's own system must
+   remember that it sent the WILL TIMING-MARK so as to discard the
+   DO/DON'T TIMING-MARK when it eventually arrives.)  Thus, in this case
+   the "appropriate place" for the insertion of the WILL TIMING-MARK is
+   the place defined by the user.
+
+   It should be noted, in both of the examples above, that it is the
+   responsibility of the system which transmits the DO TIMING-MARK to
+   discard any unwanted characters; the WILL TIMING-MARK only provides
+   help in deciding which characters are "unwanted".
+
+5.  Description of the Option
+
+
+Postel & Reynolds                                               [Page 2]
+
+
+
+RFC 860                                                         May 1983
+
+
+   Suppose that Process A of Figure 1 wishes to synchronize with B. The
+   DO TIMING-MARK is sent from A to B.  B can refuse by replying WON'T
+   TIMING-MARK, or agree by permitting the timing mark to flow through
+   his "outgoing" buffer, BUF2.  Then, instead of delivering it to the
+   terminal, B will enter the mark into his "incoming" buffer BUF1, to
+   flow through toward A.  When the mark has propagated through B's
+   incoming buffer, B returns the WILL TIMING-MARK over the TELNET
+   connection to A.
+
+      PROCESS A    TELNETconnection    PROCESS B           Terminal
+      +-----------+                +---------------+ Timing+-------+
+      |           |WILL TIMING MARK|     BUF 1     |  Mark |       |
+      |           |<---------------|--|-|-|-|-|-|--|<------|       |
+      |           |                |  |-|-|-|-|-|  |   ^   |       |
+      |           |                |     BUF 2     |   ^   |       |
+      |           |--------------->|--|-|-|-|-|-|--|------>|       |
+      |           | DO TIMING MARK |  |-|-|-|-|-|  |       |       |
+      +-----------+                +---------------+       +-------+
+                                     (NVT process).ME;
+                         Figure 1
+
+   When A receives the WILL TIMING-MARK, he knows that all the
+   information he sent to B before sending the timing mark been
+   delivered, and all the information sent from B to A before turnaround
+   of the timing mark has been delivered.
+
+   Three typical applications are:
+
+      A. Measure round-trip delay between a process and a terminal or
+         another process.
+
+      B. Resynchronizing an interaction as described in section 4 above.
+         A is a process interpreting commands forwarded from a terminal
+         by B. When A sees an illegal command it:
+
+         i.   Sends <carriage return>, <line feed>, <question mark>.
+
+         ii.  Sends DO TIMING-MARK.
+
+         iii. Sends an error message.
+
+         iv.  Starts reading input and throwing it away until it
+              receives a WILL TIMING-MARK.
+
+         v.   Resumes interpretation of input.
+
+
+
+
+
+Postel & Reynolds                                               [Page 3]
+
+
+
+RFC 860                                                         May 1983
+
+
+         This achieves the effect of flushing all "type ahead" after the
+         erroneous command, up to the point when the user actually saw
+         the question mark.
+
+      C.  The dual of B above.  The terminal user wants to throw away
+         unwanted output from A.
+
+         i.   B sends DO TIMING-MARK, followed by some new command.
+
+         ii.  B starts reading output from A and throwing it away until
+              it receives WILL TIMING-MARK.
+
+         iii. B resumes forwarding A's output to the terminal.
+
+         This achieves the effect of flushing all output from A, up to
+         the point where A saw the timing mark, but not output generated
+         in response to the following command.
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+Postel & Reynolds                                               [Page 4]
+