Network Working Group                                          J. Postel
Request for Comments: 1543                                           ISI
Obsoletes: RFCs 1111, 825                                   October 1993
Category: Informational


                      Instructions to RFC Authors

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.

Table of Contents

   1.   Introduction . . . . . . . . . . . . . . . . . . . . . . . . 1
   2.   Editorial Policy . . . . . . . . . . . . . . . . . . . . . . 3
   3.   Format Rules . . . . . . . . . . . . . . . . . . . . . . . . 4
   3a.   ASCII Format Rules  . . . . . . . . . . . . . . . . . . . . 4
   3b.   PostScript Format Rules . . . . . . . . . . . . . . . . . . 5
   4.   Header . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
   4a.   First Page Heading  . . . . . . . . . . . . . . . . . . . . 6
   4b.   Running Header  . . . . . . . . . . . . . . . . . . . . . . 7
   4c.   Running Footer  . . . . . . . . . . . . . . . . . . . . . . 7
   5.   Status Section . . . . . . . . . . . . . . . . . . . . . . . 5
   6.   Introduction Section . . . . . . . . . . . . . . . . . . . . 8
   7.   References Section . . . . . . . . . . . . . . . . . . . . . 9
   8.   Security Considerations Section  . . . . . . . . . . . . .  10
   9.   Author's Address Section . . . . . . . . . . . . . . . . .  10
   10.  Relation to other RFCs . . . . . . . . . . . . . . . . . .  10
   11.  Protocol Standards Process . . . . . . . . . . . . . . . .  11
   12.  Contact  . . . . . . . . . . . . . . . . . . . . . . . . .  11
   13.  Distribution Lists . . . . . . . . . . . . . . . . . . . .  11
   14.  RFC Index  . . . . . . . . . . . . . . . . . . . . . . . .  12
   15.  Security Considerations  . . . . . . . . . . . . . . . . .  12
   16.  References . . . . . . . . . . . . . . . . . . . . . . . .  12
   17.  Author's Address . . . . . . . . . . . . . . . . . . . . .  12
   18.  Appendix - RFC "nroff macros"  . . . . . . . . . . . . . .  13

1.  Introduction

   This Request for Comments (RFC) provides information about the
   preparation of RFCs, and certain policies relating to the publication
   of RFCs.

   The RFC series of notes covers a broad range of interests.  The core
   topics are the Internet and the TCP/IP protocol suite.  However, any



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RFC 1543              Instructions to RFC Authors           October 1993


   topic related to computer communication may be acceptable at the
   discretion of the RFC Editor.

   Memos proposed to be RFCs may be submitted by anyone.  One large
   source of memos that become RFCs is the Internet Engineering Task
   Force (IETF).  The IETF working groups (WGs) evolve their working
   memos (known as Internet Drafts or I-Ds) until they feel they are
   ready for publication, then the memos are reviewed by the Internet
   Engineering Steering Group (IESG), and if approved sent by the IESG
   to the RFC Editor.

   RFCs are distributed online by being stored as public access files,
   and a short message is sent to the distribution list indicating the
   availability of the memo.

   The online files are copied by the interested people and printed or
   displayed at their site on their equipment.  This means that the
   format of the online files must meet the constraints of a wide
   variety of printing and display equipment.  (RFCs may also be
   returned via e-mail in response to an e-mail query, or RFCs may be
   found using information and database searching tools such as Gopher,
   Wais, WWW, or Mosaic.)

   RFCs have been traditionally published and continue to be published
   in ASCII text.

   While the primary RFCs is always an ASCII text file, secondary or
   alternative versions of RFC may be provided in PostScript.  This
   decision is motivated by the desire to include diagrams, drawings,
   and such in RFCs.  PostScript documents (on paper only, so far) are
   visually more appealing and have better readability.

   PostScript was chosen for the fancy form of RFC publication over
   other possible systems (e.g., impress, interpress, oda) because of
   the perceived wide spread availability of PostScript capable
   printers.

   However, many RFC users read the documents online and use various
   text oriented tools (e.g., emacs, grep) to search them.  Often, brief
   excerpts from RFCs are included in e-mail.  These practices are not
   yet practical with PostScript files.

   PostScript producing systems are less standard than had been assumed
   and that several of the document production systems that claim to
   produce PostScript actually produce nonstandard results.

   In the future, it may be necessary to identify a set of document
   production systems authorized for use in production of PostScript



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RFC 1543              Instructions to RFC Authors           October 1993


   RFCs, based on the reasonableness of the output files they generate.

2.  Editorial Policy

   Documents proposed to be RFCs are reviewed by the RFC Editor and
   possibly by other reviewers he selects.

   The result of the review may be to suggest to the author some
   improvements to the document before publication.

   Occasionally, it may become apparent that the topic of a proposed RFC
   is also the subject of an IETF Working Group, and that the author
   could coordinate with the working group to the advantage of both.
   The usual result of this is that a revised memo is produced as a
   working group Internet Draft and eventually emerges from the IETF
   process as a recommendation from the IESG to the RFC Editor.

   In some cases it may be determined that the submitted document is not
   appropriate material to be published as an RFC.

   In some cases it may be necessary to include in the document a
   statement based on the reviews about the ideas in the document.  This
   may be done in the case that the document suggests relevant but
   inappropriate or unsafe ideas, and other situations.

   The RFC Editor may make minor changes to the document, especially in
   the areas of style and format, but on some occasions also to the
   text.  Sometimes the RFC Editor will undertake to make more
   significant changes, especially when the format rules (see below) are
   not followed.  However, more often the memo will be returned to the
   author for the additional work.

   Documents intended to become RFCs specifying standards track
   protocols must be approved by the IESG before being sent to the RFC
   Editor.  The established procedure is that when the IESG completes
   work on a document that is to become a standards track RFC the
   communication will be from the Secretary of the IESG to the RFC
   Editor.  Generally, the documents in question are Internet Drafts.
   The communication usually cites the exact Internet Draft in question
   (by file name).  The RFC Editor must assume that only that file is to
   be processed to become the RFC.  If the authors have small
   corrections to the text, they should be sent to the RFC Editor
   separately (or as a "diff"), do not send a new version of the
   document.

   In some cases, authors prepare alternate secondary versions of RFCs
   in fancy format using PostScript.  Since the ASCII text version of
   the RFC is the primary version, the PostScript version must match the



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RFC 1543              Instructions to RFC Authors           October 1993


   text version.  The RFC Editor must decide if the PostScript version
   is "the same as" the ASCII version before the PostScript version can
   be published.

   The effect of this is that the RFC Editor first processes the ASCII
   version of the memo through to publication as an RFC.  If the author
   wishes to submit a PostScript version at that point that matches the
   ASCII version (and the RFC Editor agrees that it does), then the
   PostScript version will be installed in the RFC repositories and
   announced to the community.

   Due to various time pressures on the RFC Editorial staff the time
   elapsed between submission and publication can vary greatly.  It is
   always acceptable to query (ping) the RFC Editor about the status of
   an RFC during this time (but not more than once a week).  The two
   weeks preceding an IETF meeting are generally very busy, so RFCs
   submitted shortly before an IETF meeting are most likely to be
   published after the meeting.

3.  Format Rules

   To meet the distribution constraints, the following rules are
   established for the two allowed formats for RFCs:  ASCII and
   PostScript.

   The RFC Editor attempts to ensure a consistent RFC style.  To do this
   the RFC Editor may choose to reformat the RFC submitted.  It is much
   easier to do this if the submission matches the style of the most
   recent RFCs.  Please do look at some recent RFCs and prepare yours in
   the same style.

   You must submit an editable online document to the RFC Editor.  The
   RFC Editor may require minor changes in format or style and will
   insert the actual RFC number.

   Most of the RFCs are processed by the RFC Editor with the unix
   "nroff" program using a very simple set of the formatting commands
   (or "requests") from the "ms" macro package (see the appendix).  If a
   memo submitted to be an RFC has been prepared by the author using
   nroff, it is very helpful to let the RFC Editor know that when it is
   submitted.

   3a.  ASCII Format Rules

      The character codes are ASCII.

      Each page must be limited to 58 lines followed by a form feed on a
      line by itself.



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RFC 1543              Instructions to RFC Authors           October 1993


      Each line must be limited to 72 characters followed by carriage
      return and line feed.

      No overstriking (or underlining) is allowed.

      These "height" and "width" constraints include any headers,
      footers, page numbers, or left side indenting.

      Do not fill the text with extra spaces to provide a straight right
      margin.

      Do not do hyphenation of words at the right margin.

      Do not use footnotes.  If such notes are necessary, put them at
      the end of a section, or at the end of the document.

      Use single spaced text within a paragraph, and one blank line
      between paragraphs.

      Note that the number of pages in a document and the page numbers
      on which various sections fall will likely change with
      reformatting.  Thus cross references in the text by section number
      usually are easier to keep consistent than cross references by
      page number.

      RFCs in ASCII Format may be submitted to the RFC Editor in e-mail
      messages (or as online files) in either the finished publication
      format or in NROFF.  If you plan to submit a document in NROFF
      please consult the RFC Editor first.

   3b.  PostScript Format Rules

      Standard page size is 8 1/2 by 11 inches.

      Margin of 1 inch on all sides (top, bottom, left, and right).

      Main text should have a point size of no less than 10 points with
      a line spacing of 12 points.

      Footnotes and graph notations no smaller than 8 points with a line
      spacing of 9.6 points.

      Three fonts are acceptable: Helvetica, Times Roman, and Courier.
      Plus their bold-face and italic versions.  These are the three
      standard fonts on most PostScript printers.

      Prepare diagrams and images based on lowest common denominator
      PostScript.  Consider common PostScript printer functionality and



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RFC 1543              Instructions to RFC Authors           October 1993


      memory requirements.

      The following PostScript commands should not be used:
      initgraphics, erasepage, copypage, grestoreall, initmatrix,
      initclip, banddevice, framedevice, nulldevice and renderbands.

      Note that the number of pages in a document and the page numbers
      on which various sections fall will likely differ in the ASCII and
      the PostScript versions.  Thus cross references in the text by
      section number usually are easier to keep consistent than cross
      references by page number.

      These PostScript rules are likely to changed and expanded as
      experience is gained.

      RFCs in PostScript Format may be submitted to the RFC Editor in
      e-mail messages (or as online files).  If you plan to submit a
      document in PostScript please consult the RFC Editor first.

      Note that since the ASCII text version of the RFC is the primary
      version, the PostScript version must match the text version.  The
      RFC Editor must decide if the PostScript version is "the same as"
      the ASCII version before the PostScript version can be published.

4.  Headers and Footers

   There is the first page heading, the running headers, and the running
   footers.

   4a.  First Page

      Please see the front page of this memo for an example of the front
      page heading.  On the first page there is no running header.  The
      top of the first page has the following items:

      Network Working Group

         The traditional heading for the group that founded the RFC
         series.  This appears on the first line on the left hand side
         of the heading.

      Request for Comments: nnnn

         Identifies this as a request for comments and specifies the
         number.  Indicated on the second line on the left side.  The
         actual number is filled in at the last moment before
         publication by the RFC Editor.




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      Author

         The author's name (first initial and last name only) indicated
         on the first line on the right side of the heading.

      Organization

         The author's organization, indicated on the second line on the
         right side.

      Date

         This is the Month and Year of the RFC Publication. Indicated on
         the third line on the right side.

      Updates or Obsoletes

         If this RFC Updates or Obsoletes another RFC, this is indicated
         as third line on the left side of the heading.

      Category

         The category of this RFC, one of: Standards Track,
         Informational, or Experimental.  This is indicated on the third
         (if there is no Updates or Obsoletes indication) or fourth line
         of the left side.

      Title

         The title appears, centered, below the rest of the heading.

      If there are multiple authors and if the multiple authors are from
      multiple organizations the right side heading may have additional
      lines to accommodate them and to associate the authors with the
      organizations properly.

   4b.  Running Headers

      The running header in one line (on page 2 and all subsequent
      pages) has the RFC number on the left (RFC NNNN), the (possibly a
      shortened form) title centered, and the date (Month Year) on the
      right.

   4c.  Running Footers

      The running footer in one line (on all pages) has the author's
      last name on the left and the page number on the right ([Page N]).




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RFC 1543              Instructions to RFC Authors           October 1993


5.  Status Section

   Each RFC must include on its first page the "Status of this Memo"
   section which contains a paragraph describing the type of the RFC.

   The content of this section will be one of the three following
   statements.

   Standards Track

      "This document specifies an Internet standards track protocol for
      the Internet community, and requests discussion and suggestions
      for improvements.  Please refer to the current edition of the
      "Internet Official Protocol Standards" (STD 1) for the
      standardization state and status of this protocol.  Distribution
      of this memo is unlimited."

   Experimental

      "This memo defines an Experimental Protocol for the Internet
      community.  This memo does not specify an Internet standard of any
      kind.  Discussion and suggestions for improvement are requested.
      Distribution of this memo is unlimited."

   Informational

      "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."

6.  Introduction Section

   Each RFC should have an Introduction section that (among other
   things) explains the motivation for the RFC and (if appropriate)
   describes the applicability of the protocol described.

      Some example paragraphs are:

         Protocol

            This protocol is intended to provide the bla-bla service,
            and be used between clients and servers on host computers.
            Typically the clients are on workstation hosts and the
            servers on mainframe hosts.

            or





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RFC 1543              Instructions to RFC Authors           October 1993


            This protocol is intended to provide the bla-bla service,
            and be used between special purpose units such as terminal
            servers or routers and a monitoring host.

         Discussion

            The purpose of this RFC is to focus discussion on particular
            problems in the Internet and possible methods of solution.
            No proposed solutions in this document are intended as
            standards for the Internet.  Rather, it is hoped that a
            general consensus will emerge as to the appropriate solution
            to such problems, leading eventually to the adoption of
            standards.

         Interest

            This RFC is being distributed to members of the Internet
            community in order to solicit their reactions to the
            proposals contained in it.  While the issues discussed may
            not be directly relevant to the research problems of the
            Internet, they may be interesting to a number of researchers
            and implementers.

         Status Report

            In response to the need for maintenance of current
            information about the status and progress of various
            projects in the Internet community, this RFC is issued for
            the benefit of community members.  The information contained
            in this document is accurate as of the date of publication,
            but is subject to change.  Subsequent RFCs will reflect such
            changes.

      These paragraphs need not be followed word for word, but the
      general intent of the RFC must be made clear.

7.  References Section

   Nearly all RFCs contain citations to other documents, and these are
   listed in a References section near the end of the RFC.  There are
   many styles for references, and the RFCs have one of their own.
   Please follow the reference style used in recent RFCs.  See the
   reference section of this RFC for an example.  Please note that for
   protocols that have been assigned STD numbers, the STD number must be
   included in the reference.






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RFC 1543              Instructions to RFC Authors           October 1993


8.  Security Considerations Section

   All RFCs must contain a section near the end of the document that
   discusses the security considerations of the protocol or procedures
   that are the main topic of the RFC.

9.  Author's Address Section

   Each RFC must have at the very end a section giving the author's
   address, including the name and postal address, the telephone number,
   (optional: a FAX number) and the Internet e-mail address.

10.  Relation to other RFCs

   Sometimes an RFC adds information on a topic discussed in a previous
   RFC or completely replaces an earlier RFC.  There are two terms used
   for these cases respectively, UPDATES and OBSOLETES.  A document that
   obsoletes an earlier document can stand on its own.  A document that
   merely updates an earlier document cannot stand on its own; it is
   something that must be added to or inserted into the previously
   existing document, and has limited usefulness independently.  The
   terms SUPERSEDES and REPLACES are no longer used.

   UPDATES

      To be used as a reference from a new item that cannot be used
      alone (i.e., one that supplements a previous document), to refer
      to the previous document.  The newer publication is a part that
      will supplement or be added on to the existing document; e.g., an
      addendum, or separate, extra information that is to be added to
      the original document.

   OBSOLETES

      To be used to refer to an earlier document that is replaced by
      this document.  This document contains either revised information,
      or else all of the same information plus some new information,
      however extensive or brief that new information is; i.e., this
      document can be used alone, without reference to the older
      document.

      For example:

         On the Assigned Numbers RFCs the term OBSOLETES should be used
         since the new document actually incorporate new information
         (however brief) into the text of existing information and is
         more up-to-date than the older document, and hence, replaces it
         and makes it OBSOLETE.



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RFC 1543              Instructions to RFC Authors           October 1993


   In lists of RFCs or the RFC-Index (but not on the RFCs themselves)
   the following may be used with early documents to point to later
   documents.

   OBSOLETED-BY

      To be used to refer to the newer document(s) that replaces the
      older document.

   UPDATED-BY

      To be used to refer to the newer section(s) which are to be added
      to the existing, still used, document.

11.  Protocol Standards Process

   See the current "Internet Official Protocol Standards" (STD 1) memo
   for the definitive statement on protocol standards and their
   publication [1].

   The established procedure is that when the IESG completes work on a
   document that is to become a standards track RFC the communication
   will be from the Secretary of the IESG to the RFC Editor.  Generally,
   the documents in question are Internet Drafts.  The communication
   usually cites the exact Internet Draft (by file name) in question.
   The RFC Editor must assume that only that file is to be processed to
   become the RFC.  If the authors have small corrections to the text,
   they should be sent to the RFC Editor separately (or as a "diff"), do
   not send a new version of the document.

12.  Contact

   To contact the RFC Editor send an email message to

         "RFC-Editor@ISI.EDU".

13.  Distribution Lists

   The RFC announcements are distributed via two mailing lists: the
   "IETF-Announce" list, and the "RFC-DIST" list.  You don't want to be
   on both lists.

   To join (or quit) the IETF-Announce list send a message to IETF-
   Request@cnri.reston.va.us.

   To join (or quit) the RFC-DIST list send a message to RFC-
   Request@NIC.DDN.MIL.




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RFC 1543              Instructions to RFC Authors           October 1993


14.  RFC Index

   Several organizations maintain RFC Index files, generally using the
   file name "rfc-index.txt".  The contents of such a file copied from
   one site may not be identical to that copied from another site.

15.  Security Considerations

   This RFC raises no security issues (however, see Section 6).

16.  References


   [1]  Postel, J., "Internet Official Protocol Standards", STD 1, RFC
        1540, Internet Architecture Board, October 1993.

17.  Author's Address

   Jon Postel
   USC/Information Sciences Institute
   4676 Admiralty Way
   Marina del Rey, CA  90292

   Phone: 310-822-1511
   Fax:   310-823-6714
   EMail: Postel@ISI.EDU

























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RFC 1543              Instructions to RFC Authors           October 1993


18.  Appendix - RFC "nroff macros"

   Generally, we use the very simplest nroff features.  We use the "ms"
   macros.  So, "nroff -ms input-file > output-file".  However, we could
   not get nroff to do the right thing about putting a form feed after
   the last visible line on a page and no extra line feeds before the
   first visible line of the next page.  We want:

        last visible line on page i
        ^L
        first visible line on page i+1

   So, we invented some hacks to fix this including a "sed" script
   called "fix.sh" and a "c" program we called "pg" (pg is called from
   fix).  So the command to process the file becomes:

        nroff -ms input-file | fix.sh > output-file

   Now as to the nroff features we actually use, I'll append a sample
   memo, prepared in RFC style.

   The sed script fix.sh is:

        sed -e 's/FORMFEED\[Page/        \[Page/' $* | pg -n5

The pg program is:

                     ~~~Beginning of pg program~~~

/* $Header$
 *
 *  Remove N lines following any line that contains a form feed (^L).
 *  (Why can't this be done with awk or sed?)
 *
 *  OPTION:
 *      -n#     Number of lines to delete following each ^L (0 default).
 * $Log$
 */
#include <stdio.h>
#define FORM_FEED       '\f'
#define OPTION          "n:N:"          /* for getopt() */

extern char *optarg;
extern int optind;

main(argc, argv)
int     argc;
char    *argv[];



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RFC 1543              Instructions to RFC Authors           October 1993


{
  int   c,                              /* next input char */
        nlines = 0;                     /* lines to delete after ^L */
  void  print_and_delete();             /* print line starting with ^L,
                                           then delete N lines */

/* Process option (-nlines) */

  while ((c = getopt(argc, argv, OPTION)) != EOF)
    switch(c)
    {
      case 'n' :
      case 'N' :  nlines = atoi(optarg);
                  break;
    }
/* READ AND PROCESS CHARS */

  while ((c = getchar()) != EOF)
    if (c == FORM_FEED)
      print_and_delete(nlines);  /* remove N lines after this one */
    else
      putchar(c);                /* we write the form feed */
  exit(0);
}

/* Print rest of line, then delete next N lines. */

void print_and_delete(n)
int  n;                                 /* nbr of lines to delete */
{
  int   c,                              /* next input char */
        cntr = 0;                       /* count of deleted lines */

  while ((c = getchar()) != '\n')       /* finish current line */
    putchar(c);
  putchar('\n');                        /* write the last CR */
  putchar(FORM_FEED);

  for ( ; cntr < n; cntr++)
    while ((c = getchar()) != '\n')
      if (c == EOF)
        exit(0);                        /* exit on EOF */
  putchar(c);                           /* write that last CR */
}
                        ~~~End of pg program~~~






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RFC 1543              Instructions to RFC Authors           October 1993


.pl 10.0i
.po 0
.ll 7.2i
.lt 7.2i
.nr LL 7.2i
.nr LT 7.2i
.ds LF Waitzman
.ds RF FORMFEED[Page %]
.ds CF
.ds LH RFC 1149
.ds RH 1 April 1990
.ds CH IP Datagrams on Avian Carriers
.hy 0
.ad l
.in 0
Network Working Group                                        D. Waitzman
Request for Comments: 1149                                       BBN STC
                                                            1 April 1990


.ce
A Standard for the Transmission of IP Datagrams on Avian Carriers

.ti 0
Status of this Memo

.fi
.in 3
This memo describes an experimental method for the encapsulation of IP
datagrams in avian carriers.  This specification is primarily useful
in Metropolitan Area Networks.  This is an experimental, not recommended
standard.  Distribution of this memo is unlimited.

.ti 0
Overview and Rational

Avian carriers can provide high delay, low throughput, and low
altitude service.  The connection topology is limited to a single
point-to-point path for each carrier, used with standard carriers, but
many carriers can be used without significant interference with each
other, outside of early spring.  This is because of the 3D ether space
available to the carriers, in contrast to the 1D ether used by
IEEE802.3.  The carriers have an intrinsic collision avoidance system,
which increases availability.  Unlike some network technologies, such
as packet radio, communication is not limited to line-of-sight
distance.  Connection oriented service is available in some cities,
usually based upon a central hub topology.




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RFC 1543              Instructions to RFC Authors           October 1993


.ti 0
Frame Format

The IP datagram is printed, on a small scroll of paper, in
hexadecimal, with each octet separated by whitestuff and blackstuff.
The scroll of paper is wrapped around one leg of the avian carrier.
A band of duct tape is used to secure the datagram's edges.  The
bandwidth is limited to the leg length.  The MTU is variable, and
paradoxically, generally increases with increased carrier age.  A
typical MTU is 256 milligrams.  Some datagram padding may be needed.

Upon receipt, the duct tape is removed and the paper copy of the
datagram is optically scanned into a electronically transmittable
form.

.ti 0
Discussion

Multiple types of service can be provided with a prioritized pecking
order.  An additional property is built-in worm detection and
eradication.  Because IP only guarantees best effort delivery, loss of
a carrier can be tolerated.  With time, the carriers are
self-regenerating.  While broadcasting is not specified, storms can
cause data loss.  There is persistent delivery retry, until the
carrier drops.  Audit trails are automatically generated, and can
often be found on logs and cable trays.

.ti 0
Security Considerations

.in 3
Security is not generally a problem in normal operation, but special
measures must be taken (such as data encryption) when avian carriers
are used in a tactical environment.

.ti 0
Author's Address

.nf
David Waitzman
BBN Systems and Technologies Corporation
BBN Labs Division
10 Moulton Street
Cambridge, MA 02238

Phone: (617) 873-4323

EMail: dwaitzman@BBN.COM



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