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RFC 2795 - The Infinite Monkey Protocol Suite (IMPS)

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Network Working Group                                     S. Christey
Request for Comments: 2795                         MonkeySeeDoo, Inc.
Category: Informational                                  1 April 2000

               The Infinite Monkey Protocol Suite (IMPS)

Status of this Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet standard of any kind.  Distribution of this
   memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2000).  All Rights Reserved.


   This memo describes a protocol suite which supports an infinite
   number of monkeys that sit at an infinite number of typewriters in
   order to determine when they have either produced the entire works of
   William Shakespeare or a good television show.  The suite includes
   communications and control protocols for monkeys and the
   organizations that interact with them.

Table of Contents

   1. Introduction . . . . . . . . . . . . . . . . . . . . . . .  2
   2. Objects In The Suite . . . . . . . . . . . . . . . . . . .  2
   3. IMPS Packet Structure  . . . . . . . . . . . . . . . . . .  4
   4. Infinite Threshold Accounting Gadget (I-TAG) Encoding  . .  5
   5. KEEPER Specification . . . . . . . . . . . . . . . . . . .  6
    5.1 KEEPER Message Request Codes (ZOO-to-SIMIAN) . . . . . .  7
    5.2 KEEPER Message Response Codes (SIMIAN-to-ZOO)  . . . . .  8
    5.3 Requirements for KEEPER Request and Response Codes . . .  8
    5.4 Example ZOO-to-SIMIAN Exchanges using KEEPER . . . . . .  9
   6. CHIMP Specification  . . . . . . . . . . . . . . . . . . .  9
    6.1 SIMIAN Client Requests . . . . . . . . . . . . . . . . . 10
    6.2 ZOO Server Responses . . . . . . . . . . . . . . . . . . 11
    6.3 Example SIMIAN-to-ZOO Session using CHIMP  . . . . . . . 11
   7. IAMB-PENT SPECIFICATION  . . . . . . . . . . . . . . . . . 12
    7.1 ZOO Client Requests  . . . . . . . . . . . . . . . . . . 12
    7.2 BARD Responses . . . . . . . . . . . . . . . . . . . . . 12
    7.3 Example ZOO-to-BARD Session using IAMB-PENT  . . . . . . 13
   8. PAN Specification  . . . . . . . . . . . . . . . . . . . . 13
    8.1 ZOO Requests . . . . . . . . . . . . . . . . . . . . . . 14
    8.2 CRITIC Responses . . . . . . . . . . . . . . . . . . . . 14

    8.3 Table of CRITIC Reject Codes . . . . . . . . . . . . . . 15
    8.4 Example ZOO-to-CRITIC Session using PAN  . . . . . . . . 16
   9. Security Considerations  . . . . . . . . . . . . . . . . . 16
   10. Acknowledgements  . . . . . . . . . . . . . . . . . . . . 18
   11. References  . . . . . . . . . . . . . . . . . . . . . . . 18
   12. Author's Address  . . . . . . . . . . . . . . . . . . . . 19
   13. Full Copyright Statement . . . . . . . . . . . . . . . . .20

1. Introduction

   It has been posited that if an infinite number of monkeys sit at an
   infinite number of typewriters and randomly press keys, they will
   eventually produce the complete works of Shakespeare [1] [2].  But if
   such a feat is accomplished, how would anybody be able to know?  And
   what if the monkey has flawlessly translated Shakespeare's works into
   Esperanto?  How could one build a system that obtains these works
   while addressing the basic needs of monkeys, such as sleep and food?
   Nobody has addressed the practical implications of these important
   questions [3].

   In addition, it would be a waste of resources if such a sizable
   effort only focused on Shakespeare.  With an infinite number of
   monkeys at work, it is also equally likely that a monkey could
   produce a document that describes how to end world poverty, cure
   disease, or most importantly, write a good situation comedy for
   television [4].  Such an environment would be ripe for innovation
   and, with the proper technical design, could be effectively utilized
   to "make the world a whole lot brighter" [5].

   The Infinite Monkey Protocol Suite (IMPS) is an experimental set of
   protocols that specifies how monkey transcripts may be collected,
   transferred, and reviewed for either historical accuracy (in the case
   of Shakespearean works) or innovation (in the case of new works).  It
   also provides a basic communications framework for performing normal
   monkey maintenance.

2. Objects in the Suite

   There are four primary entities that communicate within an IMPS
   network.  Groups of monkeys are physically located in Zone Operations
   Organizations (ZOOs).  The ZOOs maintain the monkeys and their
   equipment, obtain transcripts from the monkeys' typewriters, and
   interact with other entities who evaluate the transcripts.

   A SIMIAN (Semi-Integrated, Monkey-Interfacing Anthropomorphic Node)
   is a device that is physically attached to the monkey.  It provides
   the communications interface between a monkey and its ZOO.  It is

   effectively a translator for the monkey.  It sends status reports and
   resource requests to the ZOO using human language phrases, and
   responds to ZOO requests on behalf of the monkey.

   The SIMIAN uses the Cross-Habitat Idiomatic Message Protocol (CHIMP)
   to communicate with the ZOO.  The ZOO uses the Knowledgeable and
   Efficient Emulation Protocol for Ecosystem Resources (KEEPER) to
   interact with the SIMIAN.

   The ZOO obtains typewriter transcripts from the SIMIAN, which is
   responsible for converting the monkey's typed text into an electronic
   format if non-digital typewriters are used.  The ZOO may then forward
   the transcripts to one or more entities who review the transcript's
   contents.  IMPS defines two such reviewer protocols, although others
   could be added.

   For Shakespearean works, as well as any other classic literature that
   has already been published, the ZOO forwards the transcript to a BARD
   (Big Annex of Reference Documents).  The BARD determines if a
   transcript matches one or more documents in its annex.  The ZOO sends
   the transcript to a BARD using the Inter-Annex Message Broadcasting
   Protocol for Evaluating Neoclassical Transcripts (IAMB-PENT).  The
   transcripts are considered Neoclassical because (a) they are
   transferred in electronic media instead of the original paper medium,
   and (b) the word "classical" does not begin with the letter N.

   For new and potentially innovative works, the ZOO submits a
   transcript to a CRITIC (Collective Reviewer's Innovative Transcript
   Integration Center).  The CRITIC determines if a transcript is
   sufficiently innovative to be published.  The ZOO uses the Protocol
   for Assessment of Novelty (PAN) to communicate with the CRITIC.  The
   process of using PAN to send a transcript to a CRITIC is sometimes
   referred to as foreshadowing.

   A diagram of IMPS concepts is provided below.  Non-technical readers
   such as mid-level managers, marketing personnel, and liberal arts
   majors are encouraged to skip the next two sections.  The rest of
   this document assumes that senior management has already stopped

            -+-+-+-+-+-   CHIMP     -+-+-+-+-+-
            | SIMIAN/ | ----------> *         *
            | MONKEY  |             *   ZOO   *
            |         | <---------- *         *
            -+-+-+-+-+-    KEEPER   -+-+-+-+-+-
                           /    \
                          /      \
               IAMB-PENT /        \ PAN
                        /          \
                       V            V
                -+-+-+-+-+-     -+-+-+-+-+-
                *         *     *         *
                *  BARD   *     *  CRITIC *
                *         *     *         *
                -+-+-+-+-+-     -+-+-+-+-+-

3. IMPS Packet Structure

   All IMPS protocols must utilize the following packet structure.

    |Version | Seq  # | Protocol # | Reserved  | Size  |
    |         Source        |      Destination         |
    |           Data                        | Padding  |

   The Version, Sequence Number, Protocol Number, and Reserved fields
   are 32 bit unsigned integers.  For IMPS version 1.0, the Version must
   be 1.  Reserved must be 0 and will always be 0 in future uses.  It is
   included because every other protocol specification includes a
   "future use" reserved field which never, ever changes and is
   therefore a waste of bandwidth and memory. [6] [7] [8].

   The Source and Destination are identifiers for the IMPS objects that
   are communicating.  They are represented using Infinite TAGs (see
   next section).

   The Data section contains data which is of arbitrary length.

   The Size field records the size of the entire packet using Infinite
   TAG encoding.

   The end of the packet may contain extra padding, between 0 and 7
   bits, to ensure that the size of packet is rounded out to the next

4. Infinite Threshold Accounting Gadget (I-TAG) Encoding

   Each SIMIAN requires a unique identifier within IMPS.  This section
   describes design considerations for the IMPS identifier, referred to
   as an Infinite Threshold Accounting Gadget (I-TAG).  The I-TAG can
   represent numbers of any size.

   To uniquely identify each SIMIAN, a system is required that is
   capable of representing an infinite number of identifiers.  The set
   of all integers can be used as a compact representation.  However,
   all existing protocols inherently limit the number of available
   integers by specifying a maximum number of bytes to be used for an
   integer.  This approach cannot work well in an IMPS network with an
   infinite number of monkeys to manage.

   Practically speaking, one could select a byte size which could
   represent an integer that is greater than the number of atoms in the
   known universe.  There are several limitations to this approach,
   however: (a) it would needlessly exclude IMPS implementations that
   may utilize sub-atomic monkeys and/or multiple universes; (b) there
   is not a consensus as to how many atoms there are in this universe;
   and (c) while the number is extremely large, it still falls pitifully
   short of infinity.  Since any entity that fully implements IMPS is
   probably very, very good at handling infinite numbers, IMPS must
   ensure that it can represent them.

   Netstrings, i.e. strings which encode their own size, were
   considered.  However, netstrings have not been accepted as a
   standard, and they do not scale to infinity.  As stated in [9],
   "[Greater than] 999999999 bytes is bad."  Well put.

   A scheme for identifying arbitrary dates was also considered for
   implementation [10].  While it solves the Y10K problem and does scale
   to infinity, its ASCII representation wastes memory by a factor
   greater than 8.  While this may not seem important in an environment
   that has enough resources to support an infinite number of monkeys,
   it is inelegant for the purpose of monkey identification.  It is also
   CPU intensive to convert such a representation to a binary number (at
   least based on the author's implementation, which was written in a
   combination of LISP, Perl, and Java).  The algorithm is complicated
   and could lead to incorrect implementations.  Finally, the author of
   this document sort of forgot about that RFC until it was too late to
   include it properly, and was already emotionally attached to the I-
   TAG idea anyway.  It should be noted, however, that if a monkey had
   typed this particular section and it was submitted to a CRITIC, it
   would probably receive a PAN rejection code signifying the
   reinvention of the wheel.

   Since there is no acceptable representation for I-TAGs available, one
   is defined below.

   An I-TAG is divided into three sections:

              |    META-SIZE      |    SIZE     |     ID     |

   SIZE specifies how many bytes are used to represent the ID, which is
   an arbitrary integer.  META-SIZE specifies an upper limit on how many
   bits are used to represent SIZE.

   META-SIZE is an arbitrary length sequence of N '1' bits terminated by
   a '0' bit, i.e. it has the form:


   where N is the smallest number such that 2^N exceeds the number of
   bits required to represent the number of bytes that are necessary to
   store the ID (i.e., SIZE).

   The SIZE is then encoded using N bits, ordered from the most
   significant bit to the least significant bit.

   Finally, the ID is encoded using SIZE bytes.

   This representation, while clunky, makes efficient use of memory and
   is scalable to infinity.  For any number X which is less than 2^N
   (for any N), a maximum of (N + log(N) + log(log(N)))/8 bytes is
   necessary to represent X.  The math could be slightly incorrect, but
   it sounds right.

   A remarkable, elegant little C function was written to implement I-
   TAG processing, but it has too many lines of code to include in this
   margin [11].

5. KEEPER Specification

   Following is a description of the Knowledgeable and Efficient
   Emulation Protocol for Ecosystem Resources (KEEPER), which the ZOO
   uses to communicate with the SIMIAN.  The IMPS protocol number for
   KEEPER is 1.

   KEEPER is a connectionless protocol.  The ZOO sends a request to the
   SIMIAN using a single IMPS packet.  The SIMIAN sends a response back
   to the ZOO with another IMPS packet.  The data portion of the packet
   is of the following form:

   |   Version  | Type | Message ID    | Message Code  |

   Version, Type, Message ID, and Message are all 16-bit integers.

   Version = the version of KEEPER being used (in this document, the
             version is 1)

   Type = the type of message being sent.  '0' is a request; '1' is a

   Message ID = a unique identifier to distinguish different messages

   Message Code = the specific message being sent

   When a ZOO sends a KEEPER request, the SIMIAN must send a KEEPER
   response which uses the same Message ID as the original request.

5.1 KEEPER Message Request Codes (ZOO-to-SIMIAN)

   | 0    | RESERVED | Reserved                                |
   | 1    | STATUS   | Determine status of monkey              |
   | 2    | HEARTBEAT| Check to see if monkey has a heartbeat  |
   | 3    | WAKEUP   | Wake up monkey                          |
   | 4    | TYPE     | Make sure monkey is typing              |
   | 5    | FASTER   | Monkey must type faster                 |
   | 6    |TRANSCRIPT| Send transcript                         |
   | 7    | STOP     | Stop all monkey business                |
   |8-512 | FUTURE   | Reserved for future use                 |
   | 513+ | USER     | User defined                            |

5.2 KEEPER Message Response Codes (SIMIAN-to-ZOO)

   | 0    | RESERVED | Reserved                                  |
   | 1    | ASLEEP   | Status: Monkey is asleep                  |
   | 2    | GONE     | Status: Monkey is not at typewriter       |
   | 3    |DISTRACTED| Status: Monkey is distracted (not typing) |
   | 4    |NORESPONSE| Status: Monkey is not responding          |
   | 5    | ALIVE    | Status: Monkey is alive                   |
   | 6    | DEAD     | Status: Monkey is dead                    |
   | 7    | ACCEPT   | Monkey accepts request                    |
   | 8    | REFUSE   | Monkey refuses request                    |
   | 9-512| FUTURE   | Reserved for future use                   |
   | 513+ | USER     | User defined                              |

5.3 Requirements for KEEPER Request and Response Codes

   Below are the requirements for request and response codes within

   1. A SIMIAN must respond to a STATUS request with an ALIVE, DEAD,

   2. A SIMIAN must respond to a HEARTBEAT request with an ALIVE or DEAD
   code.  SIMIAN implementors must be careful when checking the
   heartbeat of very relaxed monkeys who practice transcendental
   meditation or yoga, as they may appear DEAD even if they are still

   3. A SIMIAN must respond to a STOP request with a NORESPONSE, ALIVE,
   DEAD, or GONE code.  How a SIMIAN stops the monkey is
   implementation-specific.  However, the SIMIAN should preserve the
   monkey's ALIVE status to protect the ZOO from being shut down by
   authorities or animal rights groups.  If the monkey is present but
   the SIMIAN interface is unable to verify whether the monkey is ALIVE
   or DEAD, then it must use a NORESPONSE.

   4. A SIMIAN should respond to a TYPE or FASTER request with an ACCEPT
   code, especially if there are deadlines.  The only other allowed
   responses are REFUSE, ASLEEP, GONE, NORESPONSE, or DEAD.  This
   protocol does not define what actions should be taken if a SIMIAN
   responds with REFUSE, although a BRIBE_BANANA command may be added in
   future versions.

   5. A SIMIAN must respond to a WAKEUP request with ACCEPT, REFUSE,

   6. A SIMIAN must respond to a TRANSCRIPT request by establishing a
   CHIMP session to send the transcript to the ZOO.

5.4 Example ZOO-to-SIMIAN Exchanges using KEEPER

   Assume a ZOO (SanDiego) must interact with a monkey named BoBo.
   Using KEEPER, SanDiego would interface with BoBo's SIMIAN (BoBoSIM).
   The following exchange might take place if BoBo begins to evolve
   self-awareness and independence.

   SanDiego> STATUS
   SanDiego> TYPE
   SanDiego> TYPE
   SanDiego> TYPE

   The following exchange might take place early in the morning, if
   BoBo was being poorly maintained and was working at its typewriter
   very late the night before.

   SanDiego> WAKEUP
   SanDiego> WAKEUP
   SanDiego> WAKEUP
   SanDiego> HEARTBEAT

6. CHIMP Specification

   Following is a description of the Cross-Habitat Idiomatic Message
   Protocol (CHIMP), which the SIMIAN uses to communicate with the ZOO.
   The IMPS protocol number for CHIMP is 2.

   CHIMP is a connection-oriented protocol.  A SIMIAN (the "client")
   sends a series of requests to the ZOO (the "server"), which sends
   replies back to the SIMIAN.

6.1. SIMIAN Client Requests

   SEND <resource>

     The SIMIAN is requesting a specific resource.  The resource
     The SIMIAN makes requests for FOOD or WATER by interpreting
     the monkey's behavior and environment, e.g. its food dish.  It
     requests MEDICINE or VETERINARIAN if it observes that the
     monkey's health is declining in any way, e.g. carpal tunnel
     syndrome or sore buttocks.  How the SIMIAN determines health
     is implementation-specific.  In cases where the SIMIAN itself
     may be malfunctioning, it may request a TECHNICIAN.

   REPLACE <item>

     The ZOO must replace an item that is used by the monkey during
     typing activities.  The item to be replaced may be TYPEWRITER,

   CLEAN <item>

     The SIMIAN is requesting that the ZOO must clean an item.  The
     item may be CHAIR, TABLE, or MONKEY.  How the ZOO cleans the
     item is implementation-specific.  This command is identified
     in the protocol because it has been theorized that if an
     infinite number of monkeys sit at an infinite number of
     typewriters, the smell would be unbearable [12].  If this
     theory is proven true, then CLEAN may become the most critical
     command in the entire protocol suite.

   NOTIFY <status>

     The SIMIAN notifies the ZOO of the monkey's status.  The status
     may be any status as defined in the KEEPER protocol,

   TRANSCRIPT <size>

     The SIMIAN notifies the ZOO of a new transcript from the monkey.
     The number of characters in the transcript is specified in the
     size parameter.


     The SIMIAN is terminating the connection.

6.2. ZOO Server Responses

   HELO <free text>

     Upon initial connection, the ZOO must send a HELO reply.


     The ZOO will fulfill the SIMIAN's request.


     The ZOO will fulfill the SIMIAN's request at a later time.


     The ZOO refuses to fulfill the SIMIAN's request.


     The ZOO has received the full text of a transcript that has been
     submitted by the SIMIAN.

6.3 Example SIMIAN-to-ZOO Session using CHIMP

   Assume a monkey BoBo with a SIMIAN interface named BoBoSIM, and a ZOO
   named SanDiego.  Once the BoBoSIM client has established a connection
   to the SanDiego server, the following session might take place.

      SanDiego> HELO CHIMP version 1.0 4/1/2000
      SanDiego> ACCEPT
      SanDiego> ACCEPT
      BoBoSIM>  xvkxvn i hate Binky xFnk , feEL hungry and sIck sbNf
      BoBoSIM>  so so sad sDNfkodgv .,n.,  ,HELP MEEEEEEEEE cv.Cvn l
      SanDiego> RECEIVED
      SanDiego> ACCEPT
      SanDiego> DELAY
      SanDiego> REFUSE

      SanDiego> REFUSE
      SanDiego> ACCEPT
      SanDiego> ACCEPT
      SanDiego> ACCEPT

7. IAMB-PENT Specification

   Following is a description of the Inter-Annex Message Broadcasting
   Protocol for Evaluating Neoclassical Transcripts (IAMB-PENT), which a
   ZOO uses to send transcripts to a BARD.  The IMPS protocol number is

   IAMB-PENT is a connection-oriented protocol.  A ZOO (the "client")
   sends a transcript phrases to the BARD (the "server"), which
   evaluates the transcript and notifies the ZOO if the transcript
   matches all of a classical work or a portion thereof.

7.1. ZOO Client Requests

   RECEIVETH <transcript name>

     The ZOO notifies the BARD of a new transcript to be evaluated.
     The name of the transcript is provided.

   ANON <size>

     The ZOO notifies the BARD that a transcript of the given size is
     to be provided soon.  The text of the transcript is then sent.

   ABORTETH <A2> <U3> <A3> <U4> <A4> <U5> <A5>

     The ZOO notifies the BARD that it is about to close the
     connection.  The ZOO must specify a closing message.  A2, A3,
     A4, and A5 must be accented syllables.  U3, U4, and U5 must not
     be accented.

7.2 BARD Responses

    HARK <U1> <A2> <U3> <A3> <U4> <A4> <U5> <A5>

      When the ZOO establishes a connection, the BARD must send a HARK
      command.  A2, A3, A4, and A5 must be accented syllables.  U1,
      U2, U3, U4, and U5 must not be accented.

    PRITHEE <A2> <U3> <A3> <U4> <A4> <U5> <A5>

      When a ZOO uses a RECEIVETH command to specify a forthcoming
      transcript, the BARD must respond with a PRITHEE.  A2, A3, A4,
      and A5 must be accented syllables.  U3, U4, and U5 must not be

    REGRETTETH <A2> <U3> <A3> <U4> <A4> <U5> <A5>

      If the BARD does not have the transcript in its Annex, it uses
      the REGRETTETH command to notify the ZOO.  A2, A3, A4, and A5
      must be accented syllables.  U3, U4, and U5 must not be

   ACCEPTETH  <A2> <U3> <A3> <U4> <A4> <U5> <A5>

      If the BARD has located the transcript in its Annex, it uses the
      ACCEPTETH command to notify the ZOO.  A2, A3, A4, and A5
      must be accented syllables.  U3, U4, and U5 must not be

7.3 Example ZOO-to-BARD Session using IAMB-PENT

   This is a sample IAMB-PENT session in which a ZOO (SanDiego) sends a
   transcript to a BARD (William).

     William> HARK now, what light through yonder window breaks?
     SanDiego> RECEIVETH TRANSCRIPT SanDiego.BoBo.17
     William> PRITHEE thy monkey's wisdom poureth forth!
     SanDiego> ANON 96
     SanDiego> I must be cruel, only to be kind.  Thus bad begins,
               and worse remains in front.
     William> REGRETTETH none hath writ thy words before
     SanDiego> ABORTETH Fate may one day bless my zone

8. PAN Specification

   Following is a description of the Protocol for Assessment of Novelty
   (PAN).  A ZOO uses PAN to send monkey transcripts for review by a
   CRITIC.  The IMPS protocol number for PAN is 10 [13].

   PAN is a connection-oriented protocol.  A ZOO (the "unwashed masses")
   sends a request to the CRITIC (the "all-powerful"), which sends a
   response back to the ZOO.

8.1. ZOO Requests

   COMPLIMENT <text>

     The ZOO may say something nice to the CRITIC using the given
     text.  The CRITIC does not respond to the compliment within the
     protocol.  However, it is generally believed that the CRITIC is
     more likely to accept a new transcript when a ZOO uses many

   TRANSCRIPT <name> <size>

     The ZOO notifies the CRITIC of a new transcript for review.
     The name of the transcript, plus the number of characters, are
     specified as parameters to this request.  The text of the
     transcript is then sent.


     This is an indicator that a ZOO is about to terminate the

8.2. CRITIC Responses

   SIGH <insult>

     When the ZOO establishes a connection, the CRITIC must respond
     with a SIGH and an optional insult.


     A CRITIC must respond with an IMPRESS_ME once a ZOO has made a
     TRANSCRIPT request.

   REJECT <code> REJECT 0 <text>

     When a transcript has been received, the CRITIC must respond
     with a REJECT and a code that indicates the reason for
     rejection.  A table of rejection codes is provided below.  When
     the code is 0, the CRITIC may respond using free text.  A CRITIC
     may send a REJECT before it has received or processed the full
     text of the transcript.


     The CRITIC makes this statement before terminating the


     Working group for the Infinite Monkey Protocol Suite (WIMPS)
     agreed that it is highly unlikely that a CRITIC will ever use
     this response when a REJECT is available.  It is only included
     as an explanation to implementors who do not fully understand
     how CRITICs work.  In time, it is possible that a CRITIC may
     evolve (in much the same way that a monkey might).  Should such
     a time ever come, the WIMPS may decide to support this response
     in later versions of PAN.

8.3. Table of CRITIC Reject Codes

   | 0 | <Encrypted response following; see below>
   | 1 | "You're reinventing the wheel."
   | 2 | "This will never, ever sell."
   | 3 | "Huh?  I don't understand this at all."
   | 4 | "You forgot one little obscure reference from twenty years
   |   |  ago that renders your whole idea null and void."
   | 5 | "Due to the number of submissions, we could not accept every
   |   |  transcript."
   | 6 | "There aren't enough charts and graphs.  Where is the color?"
   | 7 | "I'm cranky and decided to take it out on you."
   | 8 | "This is not in within the scope of what we are looking for."
   | 9 | "This is too derivative."
   |10 | "Your submission was received after the deadline.  Try again
   |   |  next year."

   If the CRITIC uses a reject code of 0, then the textual response
   must use an encryption scheme that is selected by the CRITIC.
   Since the PAN protocol does not specify how a ZOO may determine
   what scheme is being used, the ZOO might not be able to understand
   the CRITIC's response.

8.4. Example ZOO-to-CRITIC Session using PAN

   Below is a sample session from a ZOO (SanDiego) to a CRITIC

     NoBrainer> SIGH Abandon hope all who enter here
     SanDiego> COMPLIMENT We love your work.  Your words are like
     SanDiego> COMPLIMENT jewels and you are always correct.
     SanDiego> TRANSCRIPT RomeoAndJuliet.BoBo.763 251
     NoBrainer> IMPRESS_ME
     SanDiego> Two households, both alike in dignity,
     SanDiego> In fair Verona, where we lay our scene,
     SanDiego> From ancient grudge break to new mutiny,
     SanDiego> Where civil blood makes civil hands unclean.
     SanDiego> From forth the fatal loins of these two foes
     SanDiego> A pair of star-cross'd lovers take their life;
     NoBrainer> REJECT 2    ("This will never, ever sell.")
     SanDiego> THANKS

9. Security Considerations

   In accordance with the principles of the humane treatment of
   animals, the design of IMPS specifically prohibits the CRITIC from
   contacting the SIMIAN directly and hurting its feelings.  BARDs
   and CRITICs are also separated because of fundamental
   incompatibilities and design flaws.

   The security considerations for the rest of IMPS are similar to
   those for the original Internet protocols.  Specifically, IMPS
   refuses to learn from the mistakes of the past and blithely
   repeats the same errors without batting an eye.  Spoofing and
   denial of service attacks abound if untrusted entities gain access
   to an IMPS network.  Since all transmissions occur in cleartext
   without encryption, innovative works are subject to theft, which
   is not a significant problem unless the network contains entities
   other than CRITICs.  The open nature of BARDs with respect to
   IAMB-PENT messages allows a BARD to borrow heavily from
   transmitted works, but by design BARDs are incapable of stealing
   transcripts outright.

   The ZOO may be left open to exploitation by pseudo-SIMIANs from
   around the world.  A third party could interrupt communications
   between a ZOO and a SIMIAN by flooding the SIMIAN with packets,
   incrementing the message ID by 1 for each packet.  More heinously,
   the party could exploit the KEEPER protocol by sending a single
   STOP request to each SIMIAN, thus causing a massive denial of
   service throughout the ZOO.  The party could also spoof a CHIMP

   request or send false information such as a DEAD status, which
   could cause a ZOO to attempt to replace a monkey that is still
   functioning properly.

   In addition, if a ZOO repeatedly rejects a SIMIAN's requests
   (especially those for FOOD, WATER, and VETERINARIAN), then the ZOO
   may inadvertently cause its own denial of service with respect to
   that particular SIMIAN.  However, both KEEPER and CHIMP allow the
   ZOO to detect this condition in a timely fashion via the
   NORESPONSE or DEAD status codes.

   All BARDs are inherently insecure because they face insurmountable
   financial problems and low prioritization, which prevents them
   from working reliably.  In the rare cases when a BARD
   implementation overcomes these obstacles, it is only successful
   for 15 minutes, and reverts to being insecure immediately
   thereafter [14].  Since a CRITIC could significantly reduce the
   success of a BARD with an appropriate PAN response, this is one
   more reason why BARDs and CRITICs should always be kept separate
   from each other.

   It is expected that very few people will care about most
   implementations of CRITIC, and CRITICs themselves are inherently
   insecure.  Therefore, security is not a priority for CRITICs.  The
   CRITIC may become the victim of a denial of service attack if too
   many SIMIANs submit transcripts at the same time.  In addition,
   one SIMIAN may submit a non-innovative work by spoofing another
   SIMIAN (this is referred to as the Plagiarism Problem).  A CRITIC
   response can also be spoofed, but since the only response
   supported in PAN version 1 is REJECT, this is of little
   consequence.  Care must be taken in future versions if a
   GRUDGING_ACCEPTANCE response is allowed.  Finally, a transcript
   may be lost in transmission, and PAN does not provide a mechanism
   for a ZOO to determine if this has happened.  Future versions of
   IMPS may be better suited to answer this fundamental design
   problem: if an innovative work is lost in transmission, can a
   CRITIC still PAN it?

   Based on the number of packet-level vulnerabilities discovered in
   recent years, it is a foregone conclusion that some
   implementations will behave extremely poorly when processing
   malformed IMPS packets with incorrect padding or reserved bits
   [15] [16] [17].

   Finally, no security considerations are made with respect to the
   fact that over the course of infinite time, monkeys may evolve and
   discover how to control their own SIMIAN interfaces and send false
   requests, or to compose and submit their own transcripts.  There
   are indications that this may already be happening [18].

10. Acknowledgements

   The author wishes to thank Andre Frech for technical comments that
   tripled the size of this document, Kean Kaufmann and Amanda
   Vizedom for lectures on Shakespearean grammar, Rohn Blake for
   clarifying the nature of the entire universe, William Shakespeare
   for accents, the number 16, and the color yellow.

11. References

   [1]  The Famous Brett Watson, "The Mathematics of Monkeys and
        Shakespeare."  http://www.nutters.org/monkeys.html

   [2]  Dr. Math. "Monkeys Typing Shakespeare: Infinity Theory."

   [3]  K. Clark, Stark Mill Brewery, Manchester, NH, USA.  Feb 18,
        2000.  (personal communication).  "Good question!  I never thought
        of that!  I bet nobody else has, either.  Please pass the french

   [4]  The author was unable to find a reference in any issue of TV
        Guide published between 1956 and the date of this document.

   [5]  "Dough Re Mi," The Brady Bunch.  Original air date January 14,

   [6]  Postel, J., " Internet Protocol", STD 5, RFC 791, September 1981.

   [7]  Postel, J., "Transmission Control Protocol", STD 7, RFC 793,
        September 1981.

   [8]  Brown, C. and A. Malis, "Multiprotocol Interconnect over Frame
        Relay", STD 55, RFC 2427, September 1998.

   [9]  Internet-Draft, bernstein-netstrings-06 (expired Work in
        Progress).  D.J. Bernstein.  Inclusion of this reference is a
        violation of RFC 2026 section 2.2.

   [10] Glassman, S., Manasse, M. and J. Mogul, "Y10K and Beyond", RFC
        2550, 1 April 1999.

   [11] "My Last Theorem: A Prankster's Guide to Ageless Mathematical
        Jokes That are Funny Because They're True and People Can't Prove
        Them for Centuries."  P. Fermat.  Circa 1630.

   [12] .signature in various USENET postings, circa 1994.  Author

   [13] "Recognizing Irony, or How Not to be Duped When Reading."
        Faye Halpern.  1998.

   [14] Andy Warhol.  Circa 1964.

   [15] CERT Advisory CA-98-13.  CERT.  December 1998.

   [16] CERT Advisory CA-97.28.  CERT.  December 1997.

   [17] CERT Advisory CA-96.26.  CERT.  December 1996.

   [18] All issues of TV Guide published between 1956 and the date of
        this document.

12. Author's Address

   SteQven M. Christey
   EMail: steqve@shore.net

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