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+Network Working Group                                          J. Winett
+Request for Comments: 109                         MIT Lincoln Laboratory
+NIC: 5805                                                  24 March 1971
+
+
+          Level III Server Protocol for the Lincoln Laboratory
+                              360/67 Host
+
+Disclaimer
+
+   This material has not been reviewed for public release and is
+   intended only for use with the ARPA network.  It should not be quoted
+   or cited in any publication not related to the ARPA network.
+
+Introduction
+
+   The Lincoln Laboratory IBM 360/67 is connected to the ARPA network
+   and acts as a serving host providing access to the CP-67 virtual
+   machine operating system.  Upon completion of the Login procedure,
+   users have control of a 360 virtual machine through a virtual 1052
+   online console.  Attached to the virtual machine is a virtual card
+   reader, card punch and line printer, and a number of disk storage
+   devices.  The 360 virtual machine can be either a virtual 360/67 with
+   dynamic address translation hardware or a standard System/360.  Most
+   users run a standard 360 with 256K bytes of virtual memory and
+   operate the CMS conversational monitor system.  CMS provides
+   facilities for file creation, maintenance and manipulation, program
+   development, debugging and execution, and a number of other useful
+   utility functions.  The section in the Network Notebook on the
+   Lincoln Laboratory 360/67 more fully describes the facilities
+   available.
+
+Network Control Program
+
+   All communication with the 360/67 through the IMP are processed by a
+   Network Control Program (NCP).  The NCP operates with the Host-Host
+   Protocol described in the Network Working Group Document No. 1 dated
+   3 August 1970.
+
+Initial Connection Protocol
+
+   To create a virtual machine from the network, a pair of connections
+   must be made with the LOGGER.  The sockets to be used are assigned
+   following the Initial Connection Protocol (ICP).  The LOGGER is
+   enabled and waiting for an RTS control command for socket X'0A 0000
+   01'.  This ICP socket corresponds to home X'0A', user X'0000', and
+   tag X'01' (send gender).  Requests for connection on the ICP socket
+   are stacked until it becomes free.  If the LOGGER is willing to
+
+
+
+Winett                                                          [Page 1]
+
+RFC 109                 Level II Server Protocol           24 March 1971
+
+
+   service another network user, a 32 bit socket ID of a receive socket
+   will be sent over this initial connection and the ICP socket will
+   then be closed.  If the LOGGER is not willing to service another
+   network user, it will not complete the initial connection for the ICP
+   socket and will refuse the request by closing the connection without
+   completing it.
+
+LOGGER Protocol
+
+   Once a pair of user sockets have been assigned, the connection
+   protocol should be completed on these sockets.  The LOGGER then
+   expects to receive (on the receive socket) one 8-bit byte indicating
+   the data type which characterizes the transmission code used to
+   communicate with the network user over this pair of sockets.  A code
+   of X'01' implies 7 bit ASCII code in 8-bit bytes with the leading bit
+   zero.  A code of X'02' implies 8-bit EBCDIC code.  When the data type
+   code is received, the LOGGER will echo back the data type code over
+   the send socket followed by the message:
+
+            LINCOLN LABORATORY CP-67 ONLINE NL
+
+   in the appropriate code.  (In ASCII, NL is transmitted as CR LF).
+
+   The procedure continues according to the normal CP-67 login protocol
+   with the LOGGER performing an additional function of mapping network
+   userids and passwords into valid CP-67 userids and passwords.  This
+   mapping is specified by entries in a file (the LOGGER FILE) which the
+   LOGGER accesses.  If a network userid does not match an entry in the
+   file or if the password given does not match the corresponding
+   network password, the usual CP responses will be sent to the users.
+   Thus network access to the Lincoln Laboratory system is restricted to
+   those accounts for which an appropriate entry has been made in the
+   LOGGER FILE.
+
+   It should be noted that CP transmits a BYP code (Bypass) to suspend
+   the printing of characters keyed while a password is being entered.
+   After the password has been entered, CP transmits a RES code
+   (Restore) to resume the printing when characters are keyed.  When
+   communicating in ASCII, these character codes are converted to X'FF'
+   since no corresponding ASCII code is defined.  Refer to the Network
+   Resource Notebook for more details on CP-67 and on CMS.
+
+The NET Account
+
+   Lincoln Laboratory is providing one account which can be used by
+   network users to familiarize themselves with our time-sharing system.
+   The userid of this account is NET and the password is ARPA.  This
+   account has 900 records of storage, which can store approximately
+
+
+
+Winett                                                          [Page 2]
+
+RFC 109                 Level II Server Protocol           24 March 1971
+
+
+   720,000 characters.  NET users are free to ERASE any file on this
+   account since many different people may use this account.
+
+The SERVER Protocol
+
+   CP-67 operates on a line at a time, i.e., a group of characters are
+   processed as a line and not as a sequence of individual characters.
+   Also, the system does normally buffer input lines, that is, input is
+   not normally entered until requested by a read from the system.  With
+   IBM 2741 or 1052 terminals, the keyboard is locked until a read is
+   requested.  The virtual terminals through which network users have
+   access to the CP-67 system have been designed to support either a
+   line oriented terminal or a character oriented terminal.  When CP
+   requests a line of input, the SERVER transmits a prompting code
+   X'80'.  This character can be used to signal a user process to change
+   transmission modes and to transmit an input line.  Characters
+   received by the SERVER are buffered until a NL character is received.
+   Lines received can then be used to satisfy CP requests for an input
+   line.
+
+   CP may send out lines which may or may not end with a NL character.
+   If a line does not end with a NL character, the prompting character
+   will naturally be sent following the output line to request input to
+   a CP process.
+
+   When a user wishes to interrupt a CP process, i.e., to change modes,
+   an interrupt code X'80' should be sent to the SERVER.  This code will
+   result in an asynchronous interrupt being sent to the running
+   process, stimulating the pressing of the 'attention' button on a 2741
+   terminal.  Together with the transmission of the interrupt code, the
+   user should cause an INS to be sent over the send link.  This signal
+   will be synchronized with the interrupt code.  If the interrupt code
+   has not yet been received and processed, all characters buffered and
+   those received before the receipt of the interrupt code will be
+   flushed, i.e., deleted.  When the interrupt code is received, it will
+   be paired with the previously received INS.  If an INS is received
+   after an interrupt code has been received and processed, the INS will
+   be paired with this previously received interrupt code.
+
+   If CP has a line to send to a user after it has requested an input
+   line but before it has received any input, the SERVER will transmit
+   an INS on the user's receive link to notify the user that previously
+   sent prompting character should be retracted and that a line has been
+   or will be sent to the user.  This message line is called a
+   "warning".
+
+
+
+
+
+
+Winett                                                          [Page 3]
+
+RFC 109                 Level II Server Protocol           24 March 1971
+
+
+Graphic and Control Codes
+
+   Figure 1 gives the 8-bit codes for the EBCDIC graphics and controls.
+   Figure 2 gives the 7-bit codes for the ASCII graphics and controls.
+   The controls are tabulated and compared in Figure 3.  The standard
+   interpretation of the ASCII controls are given in Figure 4.
+
+   There are 4 ASCII codes which do not have a corresponding graphic or
+   control in the EBCDIC code.  The EBCDIC codes given to these codes
+   are as follows:
+
+                   |     Hex Code
+             ASCII |-------+--------
+            Symbol | ASCII | EBCDIC
+            -------+-------+--------
+               DC3 |  13   |  3A
+                   |       |
+                `  |  60   |  70
+                   |       |
+                \  |  5C   |  71
+                   |       |
+                ^  |  5E   |  72
+
+   There are 29 EBCDIC graphics codes and 19 EBCDIC control codes which
+   do not have a corresponding graphic or control in the ASCII code.  In
+   addition, there are 84 other EBCDIC codes whose interpretation is
+   unspecified.  Four of these codes have been chosen to correspond to
+   the ASCII control and ASCII graphics which do not have a
+   corresponding EBCDIC code.  When converting EBCDIC codes to ASCII
+   codes, the remaining 80 codes plus the 29 EBCDIC graphics and 18
+   EBCDIC controls (not counting NL) are converted into the code X'FF'.
+   The NL character is treated specially.  The NL character, EBCDIC code
+   X'15', is converted into the two character sequence CR LF, i.e.,
+   ASCII X'0D 0A'.  As stated above, the code X'80' is transmitted as a
+   prompting character whenever CP requests an input line.
+
+   On converting from ASCII to EBCDIC, if any code other than the 128
+   ASCII codes, or the interrupt codem X'80', is received, it is
+   converted to the code X'FF'.  In addition , whenever the two ASCII
+   characters CR LF are found sequentially in the input stream, they are
+   converted into the single EBCDIC character NL.
+
+   [In Figure 1, positions shown as "[?]" cannot be printed in ASCII.]
+
+
+
+
+
+
+
+
+Winett                                                          [Page 4]
+
+RFC 109                 Level II Server Protocol           24 March 1971
+
+
+        0 0  0   0   0   0   0   0   0   1   1   1   1   1   1   1   1
+        1 0  0   0   0   1   1   1   1   0   0   0   0   1   1   1   1
+        2 0  0   1   1   0   0   1   1   0   0   1   1   0   0   1   1
+        3 0  1   0   1   0   1   0   1   0   1   0   1   0   1   0   1
+   4567+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   0000|NUL|DLE|DS |   |SP | & | - |   |   |   |[?]|[?]|   |   |   | 0 |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   0001|SOH|DC1|SOS|   |   |   | / |   | a | j |[?]|[?]| A | J |   | 1 |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   0010|STX|DC2|FS |SYN|   |   |   |   | b | k | s |[?]| B | K | S | 2 |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   0011|ETX|TM |   |   |   |   |   |   | c | l | t |[?]| C | L | T | 3 |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   0100|PF |RES|BYP|PN |   |   |   |   | d | m | u |[?]| D | M | U | 4 |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   0101|HT |NL |LF |RS |   |   |   |   | e | n | v |[?]| E | N | V | 5 |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   0110|LC |BS |ETB|UC |   |   |   |   | f | o | w |[?]| F | O | W | 6 |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   0111|DEL|IL |ESC|EOT|   |   |   |   | g | p | x |[?]| G | P | X | 7 |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   1000|   |CAN|   |   |   |   |   |   | h | q | y |[?]| H | Q | Y | 8 |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   1001|   |EM |   |   |   |   |   |   | i | r | z |[?]| I | R | Z | 9 |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   1010|SMM|CC |SM |   |[1]| ! |   | : |   |   |   |   |   |   |   |   |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   1011|VT |CU1|CU2|CU3| . | $ | , | # | { | } |[?]|[?]|   |   |   |   |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   1100|FF |IFS|   |DC4| < | * | % | @ |[?]|[?]|[?]|[?]|   |   |   |   |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   1101|CR |IGS|ENQ|NAK| ( | ) | _ | ' |[?]|[?]| [ | ] |   |   |   |   |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   1110|SO |IRS|ACK|   | + | ; | > | = |[?]|[?]|[?]|[?]|   |   |   |   |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+   1111|SI |IUS|BEL|SUB| | |[2]| ? | " |[?]|[?]|[?]|[?]|   |   |   |   |
+       +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+
+                         +---+---+---+---+---+---+---+---+
+                         | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
+                         +---+---+---+---+---+---+---+---+
+                                   Code Structure
+
+                                      Figure 1.
+
+            Extended Binary-Coded Decimal Interchange Code (EBCDIC)
+
+
+
+
+
+Winett                                                          [Page 5]
+
+RFC 109                 Level II Server Protocol           24 March 1971
+
+
+            8 0   0   0   0   0   0   0   0
+            7 0   0   0   0   1   1   1   1
+            6 0   0   1   1   0   0   1   1
+            5 0   1   0   1   0   1   0   1
+        4321+---+---+---+---+---+---+---+---+
+        0000|NUL|DLE|SP | 0 | @ | P | ` | p |
+            +---+---+---+---+---+---+---+---+
+        0001|SOH|DC1| ! | 1 | A | Q | a | q |
+            +---+---+---+---+---+---+---+---+
+        0010|STX|DC2| " | 2 | B | R | b | r |
+            +---+---+---+---+---+---+---+---+
+        0011|ETX|DC3| # | 3 | C | S | c | s |
+            +---+---+---+---+---+---+---+---+
+        0100|EOT|DC4| $ | 4 | D | T | d | t |
+            +---+---+---+---+---+---+---+---+
+        0101|ENQ|NAK| % | 5 | E | U | e | u |
+            +---+---+---+---+---+---+---+---+
+        0110|ACK|SYN| & | 6 | F | V | f | v |
+            +---+---+---+---+---+---+---+---+
+        0111|BEL|ETB| ' | 7 | G | W | g | w |
+            +---+---+---+---+---+---+---+---+
+        1000|BS |CAN| ( | 8 | H | X | h | x |
+            +---+---+---+---+---+---+---+---+
+        1001|HT |EM | ) | 9 | I | Y | i | y |
+            +---+---+---+---+---+---+---+---+
+        1010|LF |SUB| * | : | J | Z | j | z |
+            +---+---+---+---+---+---+---+---+
+        1011|VT |ESC| + | ; | K | [ | k | { |
+            +---+---+---+---+---+---+---+---+
+        1100|FF |FS | , | < | L | \ | l | | |
+            +---+---+---+---+---+---+---+---+
+        1101|CR |GS | - | = | M | ] | m | } |
+            +---+---+---+---+---+---+---+---+
+        1110|SO |RS | . | > | N | ^ | n | ~ |
+            +---+---+---+---+---+---+---+---+
+        1111|SI |SU | / | ? | O | _ | o |DEL|
+            +---+---+---+---+---+---+---+---+
+    +---+---+---+---+---+---+---+---+---+---+---+---+
+            | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 |
+            +---+---+---+---+---+---+---+---+
+                     Code Structure
+
+                        Figure 2.
+
+   USA Standard Code for Information Interchange (USASCII)
+
+
+
+
+
+
+Winett                                                          [Page 6]
+
+RFC 109                 Level II Server Protocol           24 March 1971
+
+
+   CAT     EBCDIC  ASCII   TTY     PTTC    FUNCTION
+
+           NUL     NUL     NULL            Null
+   CC      SOH     SOH     SOM             Start of Heading
+   CC      STX     STX     EOA     EOA (D) Start of Text
+   CC      ETX     ETX     EOM             End of Text
+   DC      PF                      PF      Punch Off
+   FE      HT      HT      H.TAB   TAB     Horizontal Tab
+   GR      LC                      LC      Lower Case
+           DEL     DEL     RUBOUT  DEL     Delete
+           SMM                             Start of Manual Message
+   FE      VT      VT      V.TAB           Vertical Tab
+   FE      FF      FF      FORM            Form Feed
+   FE      CR      CR      RETURN          Carriage Return
+   GR      SO      SO      SO              Shift Out
+   GR      SI      SI      SI              Shift In
+   CC      DLE     DLE     DC0             Data Link Escape
+   DC      DC1     DC1     X-ON            Device Control 1
+   DC      DC2     DC2     TAPE ON         Device Control 2
+           TM                              Tape Mark
+   DC      RES                     RES     Restore
+   FE      NL                      NL      New Line
+   FE      BS      BS              BS      Backspace
+           IL                      IL      Idle
+           CAN     CAN     FE0     CAN     Cancel
+           EM      EM      S1              End of Medium
+           CC                              Cursor Control
+   CU      CU1                             Customer Use 1
+   IS      IFS     FS      S4              Info. Field Separator
+   IS      IGS     GS      S5              Info. Group Separator
+   IS      IRS     RS      S6              Info. Record Separator
+   IS      IUS     US      S7              Info Unit Separator
+   ED      DS                              Digit Select
+   ED      SOS                             Start of Significance
+   ED      FS                              Field Separator
+   DC      BYP                     BYP     Bypass
+   FE      LF      LF      LF      LF      Line Feed
+   CC      ETB     ETB     LEM     EOB (B) End of Text Block
+           ESC     ESC     S3      PRE     Escape
+           SM                              Set Mode
+   CU      CU2                             Customer Use 2
+   CC      ENQ     ENQ     WRU             Enquiry
+   CC      ACK     ACK     RU      (Y)     Acknowledge
+           BEL     BEL     BELL            Bell
+   CC      SYN     SYN     SYNC            Synchronous Idle
+   DC      PN                      PN      Punch On
+   DC      RS                      RS      Reader Stop
+   GR      UC                      UC      Upper Case
+
+
+
+Winett                                                          [Page 7]
+
+RFC 109                 Level II Server Protocol           24 March 1971
+
+
+   CC      EOT     EOT     EOT     EOT (C) End of Transmission
+   CU      CU3                             Customer Use 3
+   DC      DC4     DC4     TAPE OFF        Device Control 4
+   CC      NAK     NAK     ERROR   (N)     Negative Acknowledge
+           SUB     SUB     S2              Substitute
+   DC              DC3     X-OFF           Device Control 3
+
+                       Figure 3
+
+                Control Functions Compared
+
+   CC   (Communication Control).  A functional character intended to
+         control or facilitate transmission of information over
+         communication networks.
+
+   FE   (Format Effector).  A functional character which controls the
+         layout or positioning of information in printing or display
+         devices.
+
+   IS   (Information Separator).  A character which is used to separate
+         and qualify information in a logical sense.  There is a group
+         of four such characters, which are to be used in a hierarchical
+         order.
+
+   DC   (Device Control).  A functional character used for the control
+         of ancillary devices associated with data processing of
+         telecommunication systems, more especially switching devices
+         "on" and "off".
+
+   ED   (Edit and Mark).  A control character used by the System/360
+         Edit and Mark (EDMK) instruction for the formatting of
+         alphanumeric fields.
+
+   GB   (Graphic Control).  A control character indicating that the code
+         combinations which follow are to be interpreted in a particular
+         code table, depending upon the particular control character.
+
+   CU   (Customer Use).  A character excluded from future assignment by
+         IBM.  These "protected" codes are intended for use by customer
+         systems so that their use will not conflict with a possible
+         future IBM use.
+
+                           Figure 3 (Continued)
+
+                     Categories of Control Functions
+
+
+
+
+
+
+Winett                                                          [Page 8]
+
+RFC 109                 Level II Server Protocol           24 March 1971
+
+
+   NUL  (Null).  The all-zeros character which may serve to accomplish
+         time fill and media fill.
+
+   SOH  (Start of Heading).  A communication control character used at
+         the beginning of a sequence of characters which constitute a
+         machine-sensible address or routing information.  Such a
+         sequence is referred to as the _heading_.  An STX character has
+         the effect of terminating a heading.
+
+   STX  (Start of Text).  A communication control character which
+         precedes a sequence of characters that is to be treated as an
+         entity and transmitted through to the ultimate destination.
+         Such a sequence is referred to as _text_.  SIX may be used to
+         terminate a sequence of characters started by SOH.
+
+   ETX  (End of Text).  A communication control character used to
+         terminate a sequence of characters started with STX and
+         transmitted as an entity.
+
+   EOT  (End of Transmission).  A communication control character used
+         to indicate the conclusion of a transmission, which may have
+         contained one or more texts and any associated headings.
+
+   ENQ  (Enquiry).  A communication control character used in data
+         communication systems as a request for a response from a remote
+         station.  It may be used as a "Who Are You" (WRU) to obtain
+         identification, or may be used to obtain station status, or
+         both.
+
+   ACK  (Acknowledge).  A communication control character transmitted by
+         a receiver as an affirmative response to a sender.
+
+   BEL  (Bell).  A character for use when these is a need to call for
+         human attention.  It may control alarm or attention devices.
+
+   BS   (Backspace).  A format effector which controls the movement of
+         the printing position one printing space backward on the same
+         printing line (applicable also to display devices).
+
+   HT   (Horizontal Tabulation).  A format effector which controls the
+         movement of the printing position to the next in a series of
+         predetermined positions along the printing line (applicable
+         also to display devices and the skip function on punched
+         cards.)
+
+   LF   (Line Feed).  A format effector which controls the movement of
+         the printing position to the next printing line (also
+         applicable to display devices).
+
+
+
+Winett                                                          [Page 9]
+
+RFC 109                 Level II Server Protocol           24 March 1971
+
+
+   VT   (Vertical Tabulation).  A format effector which controls the
+         movement of the printing position to the next in a series of
+         predetermined printing lines (also applicable to display
+         devices).
+
+   FF   (Form Feed).  A format effector which controls the movement of
+         the printing position to the first predetermined printing line
+         on the next form or page (also applicable to display devices).
+
+   CR   (Carriage Return).  A format effector which controls the
+         movement of the printing position to the first printing
+         position on the same printing line (also applicable to display
+         devices).
+
+   SO    (Shift Out).  A control character indicating that the code
+         combinations which follow shall be interpreted as outside of
+         the character set of the standard code table until a Shift In
+         Character is reached.
+
+   SI    (Shift In).  A control character indicating that the code
+         combinations which follow shall be interpreted according to the
+         standard code table.
+
+   DLE   (Data Link Escape).  A communication control character which
+         will change the meaning of a limited number of contiguously
+         following characters.  It is used exclusively to provide
+         supplementary controls in data communication networks.
+
+   DC1, DC2, DC3, DC4 (Device Controls).  Characters for the control of
+         ancillary devices associated with data processing or
+         telecommunication systems, more especially switching devices
+         "on" and "off".  (If a single "stop" control is required to
+         interrupt of turn off ancillary devices, DC4 is the preferred
+         assignment.)
+
+   NAK  (Negative Acknowledge).  A communication control character
+         transmitted by a receiver as a negative response to a sender.
+
+   SYN   (Synchronous Idle).  A communication control character used by
+         a synchronous transmission system in the absence of any other
+         character to provide a signal from which synchronism may be
+         achieved or retained.
+
+
+
+
+
+
+
+
+
+Winett                                                         [Page 10]
+
+RFC 109                 Level II Server Protocol           24 March 1971
+
+
+   ETB  (End of Transmission Block).  A communication control character
+         used to indicate the end of a block of data for communication
+         purposes.  ETB is used for blocking data where the block
+         structure is not necessarily related to the processing format.
+
+   CAN  (Cancel).  A control character used to indicate that the data
+         with which it is sent is in error or is to be disregarded.
+
+   EM   (End of Medium).  A control character associated with the sent
+         data which may be used to identify the physical end of the
+         medium, or the end of the used, or wanted, portion of
+         information recorded on a medium.  (The position of this
+         character does not necessarily correspond to the physical end
+         of the medium.
+
+   SS   (Start of Special Sequence).  A control character used to
+         indicate the start of a variable length sequence of characters
+         which have special significance or which are to have special
+         handling.
+
+   ESC  (Escape).  A control character intended to provide code
+         extension (supplementary characters) in general information
+         interchange.  The Escape character itself is a prefix affecting
+         the interpretation of a limited number of contiguously
+         following characters.
+
+   FS   (File Separator), GS (Group Separator), RS (Record Separator)
+         and US (Unit Separator).  These information separators may be
+         used within data in optional fashion, except that the
+         hierarchical relationship shall be : FS is the must inclusive,
+         then GS, then RS, and US is least inclusive.  (The content and
+         length of a File, Group, Record, or Unit are not specified.)
+
+   DEL  (Delete).  This character is used primarily to "erase" or
+         "obliterate" erroneous or unwanted characters in perforated
+         tape.  (In the strict sense, DEL is not a control character.)
+
+                               Figure 4
+
+                        ASCII Control Functions
+
+
+
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+
+
+Winett                                                         [Page 11]
+
+RFC 109                 Level II Server Protocol           24 March 1971
+
+
+Endnotes
+
+   [1] - Cent sign
+   [2] - Logical not ("bent bar")
+   [?] - Graphics not in ASCII.  See Postscript or PDF version of
+         this document.
+
+
+          [This RFC was put into machine readable form for entry]
+          [into the online RFC archives by Lorrie Shiota, 10/02]
+
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+Winett                                                         [Page 12]
+