Internet Engineering Task Force (IETF) R. Sparks
Request for Comments: 6778 Tekelec
Category: Informational October 2012
ISSN: 2070-1721
Requirements for Archiving IETF Email Lists
and for Providing Web-Based Browsing and Searching
Abstract
The IETF makes heavy use of email lists to conduct its work.
Participants frequently need to search and browse the archives of
these lists and have asked for improved search capabilities. The
current archive mechanism could also be made more efficient. This
memo captures the requirements for improved email list archiving and
searching systems.
Status of This Memo
This document is not an Internet Standards Track specification; it is
published for informational purposes.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Not all documents
approved by the IESG are a candidate for any level of Internet
Standard; see Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc6778.
Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Sparks Informational [Page 1]RFC 6778 List Archiving and Search Requirements October 2012
Table of Contents
1. Introduction ....................................................2
2. List Search and Archive Requirements ............................3
2.1. Search and Browsing ........................................3
2.2. Archiving Active Lists .....................................5
2.3. Importing Messages from Other Archives .....................5
2.4. Exporting Messages from the Archives .......................5
2.5. Redundancy .................................................6
2.6. Archive Administration .....................................6
2.7. Transition Requirements ....................................7
3. Internationalized Address Considerations ........................7
4. IMAP Access .....................................................7
5. Security Considerations .........................................7
6. Acknowledgements ................................................7
7. Informative References ..........................................8
1. Introduction
The IETF makes heavy use of email lists to conduct its work.
Participants frequently need to search the archives of these lists
and have asked for improved search capabilities, particularly when
the search needs to cover a large period of time or cross several
lists. For instance, document editors, shepherds, working group
chairs, and area directors may need to review all discussion of a
particular draft. That discussion may be spread across the working
group list, one or more directorate lists, and the IETF general list.
Occasionally, work impacts multiple groups, possibly in different
areas, and the search must cover additional working group lists.
The current tools for performing these searches require several
manually coordinated steps, which are error prone. Without a local
copy of the archive (which may not be complete), searching most
working group lists requires brute force effort, aided possibly by
web search engines.
More advanced search capabilities have been constructed for a limited
subset of the available lists and are exposed in the "Email Archives
Quick Search" section of the main IETF website. While these tools
are of great assistance, there is still significant need for
improvement.
The current archive mechanism could also be made more efficient. The
current practices involve duplicate stores (for the web and ftp
interfaces), which impact storage and replication and are subject to
inconsistency.
Sparks Informational [Page 2]RFC 6778 List Archiving and Search Requirements October 2012
This memo captures the requirements for improved email list archiving
and searching systems.
2. List Search and Archive Requirements
2.1. Search and Browsing
o The system must provide a web interface for searching and browsing
archived messages.
o The system must allow browsing the entire archive of a given list
by thread or by date.
o The system must allow browsing the results of a search by thread
or by date.
Both threading based on Message-Id/References/In-Reply-To and
threading based on same subject line (modulo short prefixes
like re: and fwd:) should be taken into account.
o The system must allow searching across any subset of the archived
lists (one list, a selection of lists, or all lists).
o The system must allow searching of any combination (using AND, OR,
and NOT operators) of the following attributes. Richer search
capabilities are highly desirable.
- string occurring in sender name or email address
- date range
- string occurring in Subject
- string occurring in message body
- string occurring in message header (in particular, exact match
of Message-Id)
For instance, it would be nice to search the entire archive
for instances of a message with a given Message-ID with a
URL like <http://datatracker.ietf.org/mlarchive/
msg?id=4EA6E023.6010603@example.com>
Sparks Informational [Page 3]RFC 6778 List Archiving and Search Requirements October 2012
o Individual messages must be representable by a long-term stable
URI that can be shared between users. That is, the URI must be
suitable for reference in an email message.
- It would be preferable for that URI to appear in an Archived-At
header field in the message [RFC5064].
o Searches should be representable by a URI that can be shared
between users.
- Such URIs should be long-term stable.
- The search may be re-executed when the URI is referenced. It
is acceptable for the same URI to produce different results if
accessed at different times or by different people (for
example, by reflecting additional messages that may match the
search criteria or reflecting changes in access authorization
to lists with restricted archives).
o When the system requires credentials, it must use the
datatracker's authentication system.
- While the vast majority of archived lists have an open access
policy, some archived lists have restricted archives.
- The system must not require credentials for browsing or
searching lists with open archives. (But it is acceptable for
a user to browse or search such lists while logged in.)
- The system must make it possible to limit access to a
restricted archive based on login credentials.
- Messages from restricted archives must be distinguishable from
messages from unrestricted archives in any search results.
Sparks Informational [Page 4]RFC 6778 List Archiving and Search Requirements October 2012
2.2. Archiving Active Lists
o The archive system must accept messages handled by various mail
list manager packages.
- Lists hosted on the IETF systems are served by Mailman
[Mailman].
- Lists hosted at other organizations may use other packages.
* The archive system must accept messages through subscribing
to such an external list.
* The archive system may support other mechanisms for
accepting messages into the archive.
2.3. Importing Messages from Other Archives
Lists hosted at other systems are sometimes moved to the IETF
servers, and their archive is moved with them. The archiving system
must be able to import these archives.
o At a minimum, the archive system must be able to import mbox
formatted archives [RFC4155] [Mbox].
o The archive system should be able to import Maildir and Maildir-
like (the key characteristic being one-message-per-file) formatted
archives [Maildir].
o It is acceptable to use a separate utility to convert between
these formats before import, as long as the conversion is
lossless.
2.4. Exporting Messages from the Archives
The archive system must allow both users and administrators to export
messages.
o The archive system must support exporting messages in the mbox
format.
o The archive system should support exporting messages in the
Maildir format.
o The archive system must support exporting the entire archive of a
given list.
Sparks Informational [Page 5]RFC 6778 List Archiving and Search Requirements October 2012
o The archive system must support exporting all messages from a
given list within a given date range.
o The archive system should allow exporting the results of any
supported search query.
2.5. Redundancy
o The systems must facilitate providing archive, search, and browse
functions through geographically distributed servers.
- The systems must support a single active and single standby
server. This reflects the current operating configuration and
is expected to be the initial deployment model.
- The systems should support a single active and multiple standby
servers.
- The systems should support multiple active servers for the
search and browse functions. Support for multiple active
archive servers is not a requirement.
- The amount of traffic generated to ensure data replication
between servers should be on the order of the size of any new/
changed messages in the archives.
* It is acceptable for replication to be part of the archival
system itself (such as using the replication mechanisms from
an underlying database).
* It is acceptable to rely on replication of the underlying
filesystem objects (using rsync of one or more directory
trees, for example), but only if the objects in the
underlying filesystem are formatted such that the size of
the replication data is on the order of the size of any new/
changed messages in the archives.
2.6. Archive Administration
o The archive system must support adding and removing lists to be
archived.
o The system must allow the administrator to add messages to and
delete messages from an archived list. The system should log such
actions.
Sparks Informational [Page 6]RFC 6778 List Archiving and Search Requirements October 2012
2.7. Transition Requirements
There are many existing archived messages containing embedded links
into the existing MHonArc [MHonArc] mail archive. These links must
continue to work, but they should reach the message as archived in
the new system.
3. Internationalized Address Considerations
The archive and search functions should anticipate internationalized
email addresses as discussed in the following three documents --
[RFC6531], [RFC6532], and [IMAP-UTF8]. There is no firm requirement
at this time.
4. IMAP Access
Requirements for allowing access to the archives using IMAP are
captured in [IMAP-ARCH]. The archive system must anticipate
integrating with a system that provides IMAP access.
5. Security Considerations
Creating a new tool for searching and archiving IETF email lists does
not affect the security of the Internet in any significant fashion.
Searching can be I/O and CPU intensive. The implementors of this
tool should consider the potential for maliciously crafted searches
attempting to consume all available resources. Similarly, the
implementors should consider the potential for denial-of-service
attacks through making many connections to the browsing system or
rapid navigating within it.
Preserving the integrity of the archives is important. The
implementors should ensure that administrative access is
appropriately authenticated, and that message paths into the archive
are appropriately configured to avoid unauthorized message insertion.
6. Acknowledgements
The Tools Development team provided input into the initial
brainstorm. Text suggestions from Alexey Melnikov, Pete Resnick, S.
Moonesamy, Francis Dupont, and Murray Kucherawy have been
incorporated.
Sparks Informational [Page 7]
RFC 6778 List Archiving and Search Requirements October 2012
7. Informative References
[IMAP-ARCH] Sparks, R., "IMAP Access to IETF Email List Archives",
Work in Progress, August 2012.
[IMAP-UTF8] Resnick, P., Ed., Newman, C., Ed., and S. Shen, Ed.,
"IMAP Support for UTF-8", Work in Progress,
October 2012.
[Maildir] "Maildir", <http://en.wikipedia.org/w/
index.php?title=Maildir&oldid=503288041>.
[Mailman] "Mailman", <http://www.list.org/>.
[Mbox] "mbox", <http://en.wikipedia.org/w/
index.php?title=Mbox&oldid=515402275>.
[MHonArc] "MHonArc", <http://www.mhonarc.org/>.
[RFC4155] Hall, E., "The application/mbox Media Type", RFC 4155,
September 2005.
[RFC5064] Duerst, M., "The Archived-At Message Header Field",
RFC 5064, December 2007.
[RFC6531] Yao, J. and W. Mao, "SMTP Extension for
Internationalized Email", RFC 6531, February 2012.
[RFC6532] Yang, A., Steele, S., and N. Freed, "Internationalized
Email Headers", RFC 6532, February 2012.
Author's Address
Robert Sparks
Tekelec
17210 Campbell Road
Suite 250
Dallas, Texas 75254-4203
USA
EMail: RjS@nostrum.com
Sparks Informational [Page 8]
