Network Working Group                                        H. Flanagan
Internet-Draft                                                RFC Editor
Intended status: Informational                          January 17,                         February 28, 2017
Expires: July 21, September 1, 2017

         Digital Preservation Considerations for the RFC Series
                     draft-iab-rfc-preservation-03
                     draft-iab-rfc-preservation-04

Abstract

   The RFC Editor is both the publisher and the archivist for the RFC
   Series.  This document applies specifically to the archivist role of
   the RFC Editor.  It provides guidance on when and how to preserve
   RFCs, and the tools required to view or re-create RFCs as necessary.
   This document also highlights where gaps are in the current process,
   and where compromises are suggested to balance cost with ideal best
   practice.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on July 21, September 1, 2017.

Copyright Notice

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   4
     1.2.  Life Cycle of Digital Preservation  . . . . . . . . . . .   4
   2.  Updating Policy and Procedure . . . . . . . . . . . . . . . .   5
     2.1.  Acquisition of Documents  . . . . . . . . . . . . . . . .   6
     2.2.  Ingestion of Documents  . . . . . . . . . . . . . . . . .   6
     2.3.  Metadata and document registration  . . . . . . . . . . .   8   7
     2.4.  Normalization and standardization of canonical file
           structure and format  . . . . . . . . . . . . . . . . . .   9
       2.4.1.  'Best Effort' data retention  . . . . . . . . . . . .  10
       2.4.2.  Single format for archival purposes . . . . . . . . .  11
       2.4.3.  Holistic archiving of the computing environment . . .  12  11
     2.5.  Transformation/migration to current publication formats .  12
     2.6.  System Parameters . . . . . . . . . . . . . . . . . . . .  13
     2.7.  Financial Planning  . . . . . . . . . . . . . . . . . . .  13
   3.  Recommendations . . . . . . . . . . . . . . . . . . . . . . .  14
   4.  Summary . . . . . . . . . . . . . . . . . . . . . . . . . . .  15
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  16  15
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  16  15
   7.  Informative References  . . . . . . . . . . . . . . . . . . .  16  15
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  17

1.  Introduction

   The RFC Editor is both the publisher and the archivist for the RFC
   Series, a series of technical specifications and policy documents
   that includes foundational Internet standards [RFC6635] [RFCSERIES].
   As the publisher of these documents, the goal is to produce clear,
   consistent, and readable documents for the community using as many
   modern features, such as hyperlinks and content markup, within the
   document as necessary to convey the information the authors intended
   for their audience.  As the archivist, however, the main goal is to
   preserve both the information described and the documents themselves
   for the indefinite future.  To meet both of these goals, the RFC
   Editor must find the necessary balance between the publication needs
   of today and the archival needs of tomorrow, while acknowledging a
   finite set of resources to complete both aspects of the RFC Editor
   function.

   While many files are created during the publication process, this
   document focuses on the archival needs of RFCs and the Internet-
   Drafts (I-Ds) that are approved for publication; I-Ds before they are
   approved for publication by the appropriate stream-approving body are
   out of scope.

   To summarize, the key areas of tension between the roles of publisher
   and archivist are:

   o  the desire of the publisher to meet the needs expressed by the
      authors who want to use the latest technology within their
      documents, such as vector graphics, live links, and a rich set of
      metadata;

   o  the desire of the archivist to support only the simplest format
      for documents possible--currently held by the Series to be ASCII-
      only plain-text--so that the tools needed to view the documents
      are equally simple and resistant to changes in technology,
      resulting in a set of documents that will be easier to archive for
      at least the next several decades if not centuries.

   Through most of the history of the RFC Series, the file format for
   RFCs has been plain text with an ASCII-only character set.  This
   choice offered the simplest format likely to remain available to the
   largest number of consumers, and the one most likely to be resistant
   to changes in technology over time.  Increasingly, however, consumers
   and authors are requesting additional features that would allow for
   easy reading on a wider array of devices and retain all the metadata
   an author intended in their document.  In 2013, RFC 6949, "RFC Series
   Format Requirements and Future Development," captured the high level
   requirements for the Series; the fundamental issue being that the
   plain-text, ASCII-only documents no longer met the needs of the
   communities interested in using and producing RFCs [RFC6949].

   The assertion that plain-text, ASCII-only documents no longer meet
   the needs of the community in turn suggests that the simple archive
   process maintained by the RFC Editor is also no longer sufficient.
   More complex tools and file formats require a more complex process to
   make sure that RFCs can still be read and rendered far into the
   future.  This document describes the considerations that must inform
   any changes in policy and procedure, and describes a model for the
   RFC Series to follow when additional formats beyond the ASCII-only,
   plain-text RFCs are published.  The functional model that provides
   the framework for the archival process described in this document was
   derived from the ISO Open Archival Information System (OAIS)
   Reference Model, defined in "Space data and information transfer
   systems - Open archival information system (OAIS) - Reference model"
   [ISO14721].

1.1.  Terminology

   Acquisition: The point at which a document is accepted by the RFC
   Editor for future inclusion into the archive.

   Ingest: The point at which a digital object is assigned all necessary
   metadata to describe the object and its contents, and added to the
   archive.

   Bit stream preservation: The process of storing and maintaining
   digital objects over time, ensuring that there is no loss or
   corruption of the bits making up those objects.

   Content preservation: The retention of the ability to read, listen,
   or watch a digital file in perpetuity.  It is not about the bits
   being stored; it is about being able to access and present those bits
   to the user.

1.2.  Life Cycle of Digital Preservation

   The basic process for preserving digital information has been
   described by a variety of organizations.  From the Life cycle
   Information For E-Literature (LIFE) project in the United Kingdom, to
   the ongoing digital preservation work in the U.S.  Library of
   Congress, the basic digital preservation process is straightforward
   [LIFE] [USLOC].  Documents are acquired and processed, metadata is
   recorded, physical media is refreshed, and content is regularly
   checked to see if it is still accessible by interested parties.  The
   complexities arise when one considers the need to preserve both the
   bits of the digital objects themselves and the tools with which to
   express those bits in an environment that experiences rapid changes
   in technology.

   For most of the existence of the RFC Series, the digital preservation
   process has been fairly simple, focusing on bit stream preservation
   and relying on paper copies of digital files.

   The archival process for the RFC Series is as follows:

   1.  Acquisition: The RFC Editor database is updated to indicate an
       Internet Draft
       Internet-Draft (I-D) has been approved for publication.  At this
       point, the document is taken through the editorial process on the
       way to publication [RFC-PUB].

   2.  Ingest: The RFC is added to the archive at the time of
       publication.

   3.  Metadata creation: The details regarding an RFC, including RFC
       number, author, title, abstract, etc., are created at time of
       publication.  Additional metadata in the form of status and
       errata can be added or changed at any time, following the process
       of the originating document stream.

   4.  Bit stream preservation: This part of the process is handled as
       part of the IT system administration; all servers, disks, and
       backup technology are refreshed on a regular cycle.

   5.  Content preservation: All RFCs since January 2010 are printed out
       on standard office paper at time of publication, and the
       electronic files preserved on disk and in backups with no
       particular focus on preserving the entire computing environment
       used to create the electronic documents.  Most RFCs prior to
       January 2010 are also available on paper, but there are gaps in
       the record and issues of ownership around the paper copies before
       that date.

   When the format for RFCs transitions from plain-text, ASCII-encoded ASCII-only
   files to an XML format with multiple outputs, the archival process
   overall will become more complex.  Additional metadata and some or
   possibly all of the computing environment may need to be added to the
   archive.

2.  Updating Policy and Procedure

   RFCs are created and published as digital objects.  Unlike paper-
   based publications, a digital collection requires a focus on
   retaining the details of the technology as well as retaining the
   object itself.  Specifically, a digital archive needs to:

   o  consider the inherent instability of digital media;

   o  plan for a relatively short path to technological obsolescence;

   o  schedule regular media updates;

   o  apply predefined criteria for technology evaluation; and,

   o  ensure the continued authenticity and integrity of RFCs through
      any changes in technology.

   As the custodian and canonical source of RFCs and associated errata,
   the RFC Editor must consider how to ensure the availability and
   integrity of this document series far into the future and determine
   whether the focus must be on bit stream preservation, content
   preservation, or both.

   The RFC Editor has several advantages in acting as the digital
   archivist for the Series.  Since the RFC Editor is the publisher as
   well as the archivist, the RFC Editor controls the format of the
   material, the process for adding those materials to an archive, and
   can add any additional metadata considered necessary.  External
   materials, while a major consideration for more general archives, are
   no longer accepted by the RFC Editor.  (See "Internet Archaeology:
   Documents from Early History" for the list of non-RFC digital objects
   held by the RFC Editor [RFC-HISTORY].)

   This document describes several different preservation models that
   may fit the needs of the Series, and raises several points for
   community consideration.  Specifically, it covers information on:

   o  Acquisition of documents

   o  Ingestion of documents

   o  Metadata and document registration

   o  Normalization and standardization of canonical file structure and
      format

   o  Transformation/migration to current publication formats

   o  Content and computing environment preservation

   o  System parameters

   o  Financial impact

2.1.  Acquisition of Documents

   The acquisition process for documents intended for the archive starts
   with the submission of an approved I-D for publication.  During the
   editorial process, information such as the document metadata is
   finalized prior to publication.  The initial I-D as submitted and the
   RFC produced from it do not formally enter the archive, however,
   until the time of publication, which is considered the point of
   ingestion from an archival perspective.

2.2.  Ingestion of Documents

   Once an RFC is published, the canonical format is considered
   immutable.  At this point, the RFC Production Center, one of the
   internal roles within the RFC Editor, assigns the document metadata
   an archivist needs to identify the unique object.

   In the case of RFCs, the metadata assigned to a document at the time
   of publication includes:

   o  the RFC number

   o  ISSN

   o  publication date

   o  Digital Object Identifier (DOI)

   Additional metadata, such as author name, is assigned earlier in the
   document creation process, but it is subject to change up to the
   point of publication.  More information on metadata is available in
   section "Metadata and document registration."

   The publication of an RFC--the point at which responsibility for the
   document moves to the RFC Publisher, another internal role within the
   RFC Editor--starts the formal archival process for the documents.  At
   that time, the canonical document should be digitally signed [I-
   D.housley-rfc-and-id-signatures].  Information regarding the
   signatures and how to verify them must be made available on the RFC
   Editor website.

   In terms of deciding what to accept in the archive--a major question
   for most archives, and yet simple for the RFC Series--the RFC Editor
   accepts documents that are approved for publication by the stream
   approving body of one of the document streams: the IETF, IAB, IRTF,
   or Independent Submission streams [RFC5741].  Each document stream
   has defined processes on when and how I-Ds are approved and submitted
   to the RFC Editor for publication.  The RFC Editor does not select
   documents for publication and archiving; the RFC Editor edits and
   publishes documents as directed by the document streams.

   The RFC Editor holds no copyright on I-Ds or RFCs.  As per the IETF
   Trust Legal Provisions, the copyright for RFCs is held by the authors
   and the IETF Trust [TLP].  At any point in time, the current entities
   providing RFC Editor services must be able to release the archive of
   RFCs to the IETF Trust.

   Note: The RFC Editor is currently only responsible for RFCs; any
   associated data sets or other research data is not considered within
   the RFC Editor's mandate at this time and therefore no consideration
   to the archival requirements of such datasets is covered in this
   document.

2.3.  Metadata and document registration

   Metadata is data about data.  In the field of digital archiving, this
   is the data that clearly identifies every aspect of a document, from
   its identifier (i.e., the RFC number, the I-D draft string) to the
   size and file format of the document and more.  Metadata is stored in
   a central registry that stores information on what exactly is being
   preserved, where it is located, information on authenticity and
   provenance, and details on the hardware and/or software needed to
   view or create the documents.

   The RFC Editor maintains this registry in the form of a database that
   includes all metadata available for documents engaged in the final
   editing and publication process.  This database feeds the search
   engine on the RFC Editor website and the Info Pages available for
   every RFC (e.g., http://www.rfc-editor.org/info/rfc####).

   Current list of metadata presented in the RFC Info pages

   o  RFC number

   o  Canonical URI

   o  Title

   o  Status

   o  Updates

   o  Authors

   o  Stream

   o  Abstract

   o  Content-Type

   o  Character Set

   o  ISSN

   o  Publication date

   o  Digital Object Identifier (DOI)

   Metadata to be added in the future

   o  Publication format URIs

   Info pages also include links to: errata, IPR searches, plain text
   and XML citation files.

   In terms of best practice, all documents used as normative references
   within an RFC would also be stored in the archive.  While this is
   done automatically when the normative reference is another RFC (the
   usual case), retaining a copy of third-party documents is considered
   out of scope for the RFC Editor.  As the digital archive industry
   stabilizes, services such as Perma.CC may be a reasonable compromise
   [PERMACC].  Those services provide a permanent URI and image capture
   of online documents, with a goal of buffering against URI and online
   availability changes.

2.4.  Normalization and standardization of canonical file structure and
      format

   The normalization process is perhaps the most technically critical
   parts of digital archiving.  The purpose here is content
   preservation--making sure the data accepted for archiving are in the
   most stable and easily accessed formats possible for the long-term
   future, requiring the least amount of re-engineering and emulation of
   environments in order to view the document in the future.
   Normalization is about enabling long-term access to the information
   within a document.

   Over the history of the RFC Series, documents have been submitted for
   publication in a variety of formats, including paper in the earliest
   RFCs.  Today, the majority of RFCs are available in both a canonical
   plain-text format and PDF format.  For exceptions to this list, see
   the RFC Online Project [RFC-ONLINE].

   Currently, all RFCs are printed out to paper and stored at time of
   publication.  This has been a reasonable backup plan for several
   decades.  With few of the features one might expect from a digital
   document format (including links, metadata within the document, or
   line drawings), plain-text files do not lose much, if any,
   information when printed out to paper.  As the published formats
   change (see RFC 6949), however, printing to paper provides less value
   as much of the metadata that is an intrinsic yet invisible part of
   the rendered document will be lost in such printing.  With that in
   mind, the focus needs to change on preserving the new file formats
   electronically.

   While each RFC today is printed to paper and all electronic versions
   stored on multiple hard drives, no particular effort is made to
   ensure copies of the software used to render or read the canonical
   plain-text RFC are also archived.  The RFC Editor has several choices
   on how to adapt to a more complex set of data to archive and follow
   best practice as defined by the digital archive community:

   o  a simplified bit stream preservation model that focuses on "best
      effort" standard data retention practices, which rely on backups,
      upgrades, and regular equipment change to preserve the data, and
      assuming that emulators may be built when needed if the formats
      used go out of common use (a significant part of the existing
      model);

   o  a content preservation model that focuses on one publication
      format as a version most likely to be viewable and provide all
      necessary metadata in the future (a viable option considering the
      fact that PDF/A-3--one of the intended publication formats--was
      designed for this type of archiving) [PDF];

   o  a complex bit stream and content preservation model that focuses
      on archiving the canonical XML and the entire computing
      environment required to create, view and render all outputs from
      that file (the "best practice" when looking at this from an
      archivist's perspective).

   Those options are listed in order of least to greatest complexity and
   expense.  More detail on each option is described below.

2.4.1.  'Best Effort' data retention

   When dealing with very simple data structures such as plain-text,
   ASCII-only files, the experience of the RFC Series suggests that for
   the last few decades, hardware and operating system changes have had
   minimal impact on the document files being stored.  While a complete
   failure of an operating system migration in the past had corrupted
   the data set, that situation represents a somewhat different problem
   than the tools themselves changing such that plain-text files are not
   easily read with existing technology.  Given that the basic plain-
   text format and ASCII encoding remain in common use, the standard
   protections against file corruption and data loss, such as disk
   mirroring, off-site backups, and periodic restoration testing will
   continue to provide access to the entirety of the RFC Series for the
   foreseeable future.  As has been pointed out, both in this document
   and in broader community discussion, that is not sufficient when one
   moves into more complex formats such as XML, HTML, PDF, or other
   proprietary formats offered by today's large IT companies.  The risk
   of technological change resulting in the file formats mentioned being
   deprecated or changed without backwards compatibility is fairly high
   when looking at a future of decades or centuries.

   It is recommended that this model of archiving the RFC Series cease
   to be the primary model after the plain-text, ASCII-only format is no
   longer the canonical format.  Best effort data retention is a
   necessary but not sufficient level of effort for preserving a digital
   archive.  For more guidance on how to define best effort data
   retention, the section on "Media and Formats, Summary
   Recommendations" in the latest version of the Digital Preservation
   Handbook provides useful and concrete information [DPC].

2.4.2.  Single format for archival purposes

   If one ascribes to the idea that preserving the information described
   by a document, rather than the document itself, is the primary
   purpose of an archive, then focusing efforts on a single file format
   is a reasonable option.  Some well-supported archival tooling
   projects follow this route, such as Archivematica
   <https://www.archivematica.org/wiki/Main_Page >.  By selecting a
   feature-rich yet fundamentally stable file format for documents, an
   organization may avoid expensive whole-environment reconstruction in
   order to view the document.  The PDF/A formats were designed to be an
   archival format for electronic documents, and PDF/A-3 is one of the
   options intended for publication as the RFC Series moves from a
   plain-text canonical format to an XML canonical format with multiple
   publication formats.  A PDF/A-3 file can be produced that embeds the
   XML from which the PDF/A-3 file was created, which in turn allows for
   both original and rendered document validation--if one has the
   correct tools available to see the source of the PDF/A-3 file
   [I-D.iab-rfc-use-of-pdf].  The XML is not otherwise visible when
   viewing the PDF/A-3 file through typical PDF reader software.

   When looking at the need to archive RFCs in a resource-limited
   environment, a content preservation-only model has merit, but it is
   not without risks.  First, PDF/A-3 will not be the canonical format,
   but is intended to be one of the rendered outputs.  It may contain
   rendering bugs that were not intended to be in the document.  Second,
   while the various PDF/A formats were designed to be archival, it has
   not been put to the test of time to determine if will actual live up
   to its design goals.

   It is a valid option to consider, but the risks, priorities, and
   costs must be discussed by the community before a decision is made to
   follow this path.  The best option may be to combine this with one of
   the other methods of archiving described in this document to help
   minimize both risk and cost.

2.4.3.  Holistic archiving of the computing environment

   Preserving everything published through the RFC Editor in order to
   have a permanent record of information, standards, and best practice,
   is arguably the whole point of being an archival series.  One can
   argue that it is not only about the information described in an RFC,
   it is also about supporting Intellectual Property Rights (IPR) and
   retaining the history of the Internet.  In following this model,
   however, one must consider the complexity of the archival environment
   as matching, and possibly exceeding, the complexity of the file
   formats being preserved.

   Consider a future where XML has been obsoleted for half a century,
   HTML5 was a format used three to four human generations ago, and PDF/
   A-3 no longer supported by any existing company's reading software.
   In order for RFCs that were produced with XML as their canonical
   format, an archive must not only hold the data, it must also hold the
   entire computing environment that allows the data to be rendered and
   viewed.  Operating systems and hardware on which those OSs can run,
   each major version of each piece of software used or relied upon
   during the publication of an RFC, browsers and readers for HTML, PDF,
   and any other publication format, must be preserved in some fashion.
   This is considered best practice when archiving digital documents.
   It is also the most expensive, and the cost only increases over time
   as more and more instances of the computing environment must be
   preserved over the lifetime of the Series.

   This is a valid option to consider, but the sheer scope of resources
   required suggests that this must be discussed by the community before
   a decision is made.  Pursuing this may require an entirely different
   paradigm for the RFC Editor than what has been considered in the
   past; expanding the scope and resources for the RFC Editor, finding a
   third-party to take over the responsibilities of archiving, or some
   other option may be necessary.

2.5.  Transformation/migration to current publication formats

   Noting that normalization is a complex subject, it is important to
   consider what to do to mitigate the risk of failure of the
   normalization process.

   The RFC Editor is responsible for making RFCs available to the
   Internet community.  The canonical version of an RFC does not change
   once published; any formats officially rendered from the canonical
   version, however, may change.  One way to mitigate the need to
   preserve the entire computing environment for an RFC, including web
   browsers and PDF readers, would be to take advantage of the non-
   canonical nature of the publication formats and re-render them from
   the canonical source at the point that browser or reader technology
   has changed sufficiently to make RFCs largely unavailable to 'modern'
   tools.

   For example, the RFC Editor may develop a practice of starting an
   annual review of the tools needed to view the publication formats
   created by the RFC Editor, and determine whether or not the current
   common and popular reader technologies (i.e., web browsers, PDF
   viewers, e-readers) can view the existing publication formats.
   During that review, the RFC Editor would work with the community to
   determine if the current publication formats meet the needs of the
   community, and whether any should be retired or added to improve the
   availability of information to the community at that time.

2.6.  System Parameters

   While the industry best practice on the backup and restoration of
   data is not sufficient as a long-term archival solution, it is still
   a necessary part of keeping the Series available now and into the
   future.  In the past, nearly 800 RFCs had to be manually transcribed
   from paper back to electronic format due to a failed server migration
   and insufficient backups.

   The underlying servers hosting the tools, database, RFCs, and errata
   are the physical link in the archive environment.  While such systems
   cannot and should not remain static and unchanging, there must be
   clear documentation regarding the environment, in particular the
   storage, backups, and recovery processes for all RFC-related
   material.  The documentation must include information on the refresh
   cycle for the physical storage and backup media and describe a
   regular cycle of data restoration and/or migration testing.

2.7.  Financial Planning

   Having a digital archive policy provides input into the budget
   process.  The main costs associated with digital archives come from
   the complexity and quantity of the material being archived, as
   described in the section on Normalization.  To quote the Digital
   Protection Conservancy Handbook:

      The complexity of the material submitted and number of objects
      acquired generally has more impact on costs than the total storage
      size.  The type and variety of formats accepted into the
      repository will also affect cost, because for example proprietary
      formats are likely to be more difficult and expensive to manage in
      the long term.  It may be possible to reduce costs by limiting the
      formats the repository will accept, or transforming material into
      a standard common format.  This can be done to reduce the number
      of file types and possibly reducing the storage size.  However, it
      is also necessary to realise that due to storage redundancies
      required for back up each gigabyte of deposited data requires more
      than one gigabyte of disk space in repository storage. --
      http://www.dpconline.org/advice/preservationhandbook/
      institutional-strategies/costs-and-business-modelling

   Estimating potential costs and providing figures is outside of the
   scope of this document, but it should be noted that costs are a major
   factor when determining what level of archival practice an
   organization will follow.

3.  Recommendations

   Given the need to balance cost and complexity with retention of
   information for historic, legal, and informational purposes,
   preservation efforts should focus on the XML canonical format files,
   the PDF/A-3 format files, the xml2rfc tool and its documentation, and
   at least two PDF reader applications capable of extracting the
   embedded XML.  Care should be taken that the software being included
   in this archive has a provision for free copies for backup or archive
   purposes.  All other formats and the overall computing environment
   should be stored as described in "best effort" data retention, which
   should in turn be described in the appropriate vendor contract for
   the RFC Publisher.

   Particular preservation efforts should be made by:

   o  choosing a format designed for archiving RFCs (PDF/A-3)

   o  embedding the canonical XML format within the PDF/A-3 file for
      RFCs

   o  adding a digital signature and checksum for the canonical XML and
      the PDF/A-3 files

   o  retaining a copy of the plain-text or XML file submitted for
      approved I-Ds

   o  retaining all major versions of the tools and their associated
      documentation used to acquire and ingest an RFC

   o  retaining the final XML file as well as the PDF/A-3 file with the
      embedded XML

   o  retaining at least two software reader applications to ensure the
      PDF/A-3 and XML files can be viewed in the future

   o  partnering with other digital archives around the world to mirror
      copies of the target data

   In order to control costs and focus the archiving effort on the
   entire content of an RFC, including the metadata and other features
   embedded within each RFC published in more than just plain text,
   printing each RFC upon publication to paper is no longer reasonable.
   Proper data storage and mirrored copies of RFCs provides more
   efficient and effective copies in case of catastrophic failure of the
   existing archive of material.

   Particular focus should be given to finding partners that specialize
   in digital preservation to ingest RFCs.  Ideally, they will ingest
   all material associated with an RFC, including all metadata, digital
   signatures, and the approved Internet-Draft that was submitted to the
   RFC Editor.  The possibilities and options should be discussed with
   each archival partner; at minimum, they must ingest copies of RFCs as
   they are published, with the basic metadata associated with each
   document.

   Preservation efforts should be reviewed and validated through a bi-
   annual audit that will verify that the targeted content and all its
   associated metadata can be read with existing tools.  The full
   process from acquisition to ingest should be reviewed to ensure that
   best current practice is being followed from a digital archive
   community perspective.  Since the overall model for the RFC Editor-
   maintained digital archive follows the OAIS Reference model, the
   associated audit guidelines should be followed.  While the RFC Editor
   does not seek to be recognized as 'OAIS-compliant' at this time, use
   of the ISO standard, "Audit and Certification of Trustworthy Digital
   Repositories," would provide a solid, accepted method for structuring
   an audit for this digital archive [ISO16363].

4.  Summary

   The RFC Series is worth archiving.  It contains the history of the
   early Internet, as well as some of the key standards for Internet
   technology and best practice today.  Who knows what the community
   will create in the future?  There are many ways to preserve the
   Series, from relying on preservation of the bits, to focusing on a
   single file format, to preserving the entire computing environment.
   Each possibility, or the permutations from them, involves risks and
   varying levels of resources.  The goal of this document is to
   describe the possibilities and associated risks so that the community
   can come to an informed decision regarding what they are willing to
   see supported far into the future.

5.  IANA Considerations

   This document has no IANA actions.

6.  Security Considerations

   This document assumes that the origination of RFCs via the RFC Editor
   is secure and trusted.  With that assumption, the activities
   discussed in this document do not affect the security of the
   Internet.

7.  Informative References

   [I-D.iab-rfc-use-of-pdf]
              Hansen, T., Masinter, L., and M. Hardy, "PDF for an RFC
              Series Output Document Format", draft-iab-rfc-use-of-
              pdf-02 (work in progress), May 2016.

   [I-D.housley-rfc-and-id-signatures]
              Housley, R., "Digital Signatures on RFC and Internet-Draft
              Documents", draft-housley-rfc-and-id-signatures-03 (work
              in progress), June 2016.

   [DPC]      DigitalPreservationCoalition, "Digital Preservation
              Handbook", 2012,
              <http://www.dpconline.org/advice/preservationhandbook>.

   [ISO14721]
              International Organization for Standardization, ""Space
              data and information transfer systems -- Open archival
              information system (OAIS) -- Reference model"", ISO
              14721:2012 , 2012.

   [ISO16363]
              International Organization for Standardization, ""Space
              data and information transfer systems -- Audit and
              Certification of Trustworthy Digital Repositories"", ISO
              16363:2011 , 2011.

   [LIFE]     Hole, B., "LIFE^3: Predictive Costing of Digital
              Preservation", July 2010,
              <http://www.life.ac.uk/3/docs/Hole_pasig_v1.pdf>.

   [PDF]      International Organization for Standardization,
              ""Electronic document file format for long-term
              preservation -- Part 3: Use of ISO 32000-1 with support
              for embedded files (PDF/A-3)"", ISO 19005-3 , 2012.

   [PERMACC]  "Perma.CC", n.d., <http://perma.cc/>.

   [RFC-HISTORY]
              RFC Editor, "Internet Archaeology: Documents from Early
              History", n.d., <http://www.rfc-editor.org/history.html>.

   [RFC-ONLINE]
              RFC Editor, "History of RFC Online Project", n.d.,
              <http://www.rfc-editor.org/rfc-online-2000.html>.

   [RFC-PUB]  RFC Editor, "RFC Editor Publication Process", n.d.,
              <http://www.rfc-editor.org/pubprocess.html>.

   [RFCSERIES]
              RFC Editor, "Overview of RFC Document Series", n.d.,
              <http://www.rfc-editor.org/RFCoverview.html>.

   [TLP]      IETF Trust, "IETF Trust Legal Provisions", n.d.,
              <http://trustee.ietf.org/docs/
              IETF-Trust-License-Policy.pdf>.

   [USLOC]    Library of Congress, "Life Cycle Models for Digital
              Stewardship", n.d.,
              <http://blogs.loc.gov/digitalpreservation/2012/02/
              life-cycle-models-for-digital-stewardship/>.

   [RFC5741]  Daigle, L., Ed., Kolkman, O., Ed., and IAB, "RFC Streams,
              Headers, and Boilerplates", RFC 5741,
              DOI 10.17487/RFC5741, December 2009,
              <http://www.rfc-editor.org/info/rfc5741>.

   [RFC6635]  Kolkman, O., Ed., Halpern, J., Ed., and IAB, "RFC Editor
              Model (Version 2)", RFC 6635, DOI 10.17487/RFC6635, June
              2012, <http://www.rfc-editor.org/info/rfc6635>.

   [RFC6949]  Flanagan, H. and N. Brownlee, "RFC Series Format
              Requirements and Future Development", RFC 6949,
              DOI 10.17487/RFC6949, May 2013,
              <http://www.rfc-editor.org/info/rfc6949>.

Author's Address

   Heather Flanagan
   RFC Editor

   Email: rse@rfc-editor.org
   URI:   http://orcid.org/0000-0002-2647-2220