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RFC 1926 INFORMATIONAL HUMOR · NETWORKING

IP over ATM (joke): An Experimental Encapsulation of IP Datagrams on Top of ATM

An April Fools joke about transmitting IP datagrams over sound waves

On rfc-editor.org ↗
PUBLISHED
April 1996
AUTHORS
J. Eriksson
STREAM
INDEPENDENT
DEFAULT FREQUENCY
440 Hz (concert A)
FREQUENCY RANGE
440 to 784 Hz
MODULATION
Morse code
DOI
10.17487/RFC1926

RFC text

Contents
Original text · RFC Editor View on rfc-editor.org ↗ 
Network Working Group                                        J. Eriksson
Request for Comments: 1926                                       KTH NOC
Category: Informational                                     1 April 1996


      An Experimental Encapsulation of IP Datagrams on Top of ATM

Status of this Memo

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

Abstract

   This RFC describes a method of encapsulating IP datagrams on top of
   Acoustical Transmission Media (ATM).  This is a non-recommended
   standard.  Distribution of this memo is unnecessary.

Overview

   The modern laptop computer of today often contains the hardware
   needed to perform wireless communications by using Acoustical
   Transmission Media, i.e. sound waves.  Until this moment there has
   been no standard on how to run IP on such media.  This document is an
   attempt to fill this silence.

Frame transmission

   The IP datagram is divided into four-bit chunks, in network beep
   order, and converted to characters according to the table below.  A
   single "b" character is prepended as a frame start signal, the
   characters are then transmitted in ordinary morse code by modulating
   a steady tone on and off.  The frequency of this tone is also known
   as the Acoustical Signature (AS number) of the sender.

        Bits    Character       Bits    Character

        0000    "i"             1000    "u"
        0001    "t"             1001    "m"
        0010    "s"             1010    "v"
        0011    "a"             1011    "f"
        0100    "n"             1100    "w"
        0101    "h"             1101    "l"
        0110    "d"             1110    "k"
        0111    "r"             1111    "g"

   To allow more than one Local Acoustical Network (LAN) to coexist the
   use of different AS numbers for different LANs is suggested.  This
   document proposes seven standard AS numbers to be used, see the table
   below for details.

        Name   Frequency

        "a"     440 Hz
        "b"     494 Hz
        "c"     523 Hz
        "d"     587 Hz
        "e"     659 Hz
        "f"     698 Hz
        "g"     784 Hz

   It is assumed that for normal operation AS number "a", 440 Hz will be
   used.

Frame reception

   The above process is simply performed backwards.

Security Considerations

   The author assumes that the users take whatever precautions that are
   necessary before attempting to use this protocol in any crowded area.

Author's Address

   Johnny Eriksson
   KTH NOC
   EMail: bygg@sunet.se

   or

     -... -.-- --. --. @ ... ..- .- . - .-.-.- ... .

AI ELI5

On this page
PROBLEMLaptops have audio hardware but no standard for sending IP packets over sound.
MECHANISMThis RFC (published April 1, 1996) proposes encapsulating IP datagrams as Morse code transmitted via sound waves at different frequencies (440 Hz to 784 Hz) to create separate Local Acoustical Networks (LANs).
AN APRIL FOOLS PRANKA clever pun playing on the acronym ATM (normally Asynchronous Transfer Mode), reinterpreted as Acoustical Transmission Media.

§1The Setup

This RFC is an April Fools joke, published on 1 April 1996. It proposes a method of encapsulating IP datagrams on top of Acoustical Transmission Media (ATM), a clever pun on the real networking standard Asynchronous Transfer Mode (ATM). The joke hinges on the observation that laptops have audio hardware that could theoretically transmit data as sound.

The proposal is presented in deadpan technical language, complete with a frame format, modulation scheme, frequency assignments, and security considerations.

This is a silly April Fools joke pretending you can send Internet data by making beeping sounds, using the same letters as a real networking technology.

§2The Encoding Scheme

The IP datagram is divided into 4-bit chunks and converted to characters using a 16-character table (each bit pattern from 0000 to 1111 maps to a letter like 'i', 't', 's', 'a', etc.). A single 'b' character is prepended as a frame start signal. The characters are then transmitted in Morse code by modulating a steady tone on and off at one of seven standard frequencies: 440 Hz (a), 494 Hz (b), 523 Hz (c), 587 Hz (d), 659 Hz (e), 698 Hz (f), or 784 Hz (g).

Different frequencies represent different Local Acoustical Networks (LANs). The default AS (Acoustical Signature) number is 'a', at 440 Hz. Reception is simply the reverse process.

Convert each bit of the data to a letter, send that letter as Morse code in sound form at a certain pitch, and different pitches mean different networks.

§3Why This Is Funny

The RFC is funny because it takes a ridiculous premise (networking over beeping) and treats it with complete technical seriousness. It includes proper sections (Overview, Frame transmission, Frame reception, Security Considerations), standard frequency assignments, and even practical advice (users should take precautions in crowded areas).

The author's email address at the end is signed in actual Morse code, a final touch to the punchline. The RFC exists in the formal IETF archive as a historical artifact of April Fools humor.

It's funny because it's written like a serious technical document about something absurd—sending network data as beeping sounds.