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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>SiocLog: Providing IRC discussion logs as Linked Data</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Tuukka Hastrup</string-name>
          <email>Tuukka.Hastrup@iki.fi</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Uldis Boajrs</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>John G. Breslin</string-name>
          <email>john.breslin@nuigalway.ie</email>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>DERI, National University of Ireland</institution>
          ,
          <addr-line>Galway</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>School of Engineering and Informatics, National University of Ireland</institution>
          ,
          <addr-line>Galway</addr-line>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>University of Jyvskyl</institution>
          ,
          <country country="FI">Finland</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>The SiocLog software application supports social networking and online collaboration by observing the instant messaging (IM) discussions on some public IRC channels, archiving the discussion logs, and publishing them as Linked Data on the Web. The application provides Web addresses (http URIs) for information from the discussion channels, including the daily discussions and the participants. Linked Data practices and the SIOC vocabulary provide a standard way to ensure that all parties can easily access the raw data, e.g., to create mash-ups. The chat participants can further provide their Web ID to link to their FOAF personal prole, and the FOAF prole can conrm this link in return, creating trust. Consuming FOAF data helps to avoid re-entry of personal data and searching for friends on yet another social site. The prole can also link to the person's accounts on other social forums, thus connecting their divided social presence on the Web. We present how the software is being used on some IRC channels, and describe how this work connects IRC to the greater Web of Data.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>Instant messaging is one major form of social interaction and online
collaboration, but it is traditionally disconnected from the Web, not least because of
its immediate nature and the shortness of the messages. Various services try to
bridge this gap. An area that pertains to social data is observing, archiving,
analysing, and publishing of the discussions. Linked Data provides a framework
for publishing data on the Web, parallel to documents.</p>
      <p>After the background information in this section, we rst motivate and then
introduce the design and implementation of the SiocLog software 4 (see Figure 1),
which observes discussions on Internet Relay Chat (IRC) and publishes them as
Linked Data. Subsections describe how SiocLog deploys the SIOC vocabulary
and the concept of a Web ID, as well as detail the software architecture. Sections
on validation of the results and comparison to related work follow before we
conclude in the end.</p>
    </sec>
    <sec id="sec-2">
      <title>4 http://irc.sioc-project.org/</title>
      <p>
        Internet Relay Chat (IRC) [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] is one of the earliest instant messaging systems,
where people chat virtually on discussion channels. IRC continues to have an
important role in certain circles, including Free Software development 5 as well
as the World Wide Web Consortium 6 [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], and it would be useful to interlink
these discussions as well as to provide a useful service for accessing and
referring to conversations in these channels. Also, multiple active IRC discussion
channels exist related to the Semantic Web and Linked Data. Due to its open
nature, various systems enhance and cooperate on the chat networks that use
the IRC protocol. Software agents, known as bots short for robot, employ the
same interface to the system as application software.
      </p>
      <p>Although the protocol lets people to choose any vacant nickname when they
connect to a network and thus to freely assume a chat persona each time, some
networks provide an additional service called nickserv for people to register
their nicknames and to authenticate themselves repeatably.</p>
    </sec>
    <sec id="sec-3">
      <title>5 http://freenode.net/</title>
      <p>
        6 http://www.w3.org/2001/12/zakim-irc-bot
1.2
Linked Data [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] practices build a Web of Data to enhance the Web (traditionally
of pages, or documents). It means that each piece of information can be accessed
by following links: On conventional Web pages, a reader can follow links from
page to page. Also, all documents (and some fragments) have a Web address that
anyone can refer to from anywhere. Similarly, Linked Data documents apply this
principle of linking by making all their information referrable via Web addresses
on the Web of Data by providing a machine-readable (RDF) version of the data,
using well-known vocabularies to represent the content. Thus, anyone can easily
access the raw data based on standards, e.g., to create mash-ups.
      </p>
      <p>One way to access Linked Data is SPARQL, which is the Linked Data
counterpart to and similar to SQL. SPARQL is supported by software libraries such
as Redland7, as well as by utility programs such as cli.php of ARC2 Starter
Pack8. Tools such as NG4J9 and Squin10 strive to make the subtask of
downloading data from the Web completely implicit in the declarative SPARQL queries.
1.3</p>
      <p>
        Semantically-Interlinked Online Communities (SIOC)
Semantically-Interlinked Online Communities (SIOC) [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] is the standard
vocabulary for expressing social content as RDF and Linked Data. In its basic form,
it provides classes and properties to describe sites, forums, users and posts. An
additional vocabulary module provides more specic versions of these, such as
message boards, chat channels, blog posts, and polls.
      </p>
      <p>
        SIOC is currently used to represent information from various types of social
software such as collaborative work environments, bulletin boards and
microblogging systems [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ][
        <xref ref-type="bibr" rid="ref10">10</xref>
        ].
1.4
      </p>
      <p>
        Web ID
A Web ID [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] is a Web address that identies a person as a Linked Data item,
instead of identifying a document such as a homepage or a personal prole.
Following the Linked Data principles, the Web ID should still lead to a document
with information about the person. For example, a Web ID such as http://
example.com/author#person could lead to the Web page http://example.
com/author.html or, if the client accepts RDF, to the Linked Data document
http://example.com/author.rdf .
      </p>
      <p>The standard way to describe personal prole information is the Friend of a
Friend (FOAF) vocabulary.</p>
    </sec>
    <sec id="sec-4">
      <title>7 http://librdf.org/</title>
      <p>8 http://tuukka.sioc-project.org/arc2-starter-pack
9 http://www4.wiwiss.fu-berlin.de/bizer/ng4j/
10 http://squin.sourceforge.net/</p>
      <sec id="sec-4-1">
        <title>Motivation</title>
        <p>The system described here is a specic case of the Semantic Web and Linked
Data approaches, and as such, its usefulness relies mostly in the adoption of
these technologies. The general pursuit of interlinking online communities using
these approaches has centered on the SIOC vocabulary. Most work around SIOC
this far is on publishing social data, whereas data consumers are necessary for
completing most use cases. With this background, the system here is mostly a
publisher, with same motivation as earlier work on SIOC publishers, but it starts
to consume some data as well.</p>
        <p>Regarding the specics of the application domain, IRC plays an important
role in connecting people online and in enabling their collaboration. IRC
conversations are a popular collaboration tool for Free and Open Source Software
developers and other communities.</p>
        <p>Such conversations may contain useful knowledge, such as answers to
frequently asked questions, new ideas, analysis of bugs, etc. In order to preserve
this information, channel managers would often record logs of conversations on
the channel and post them online.</p>
        <p>However, developers may participate in conversations on multiple channels,
and similar topics may be discussed in a number of related channels (e.g., #foaf,
#sioc, and #swig are all related to Linked Data). A limitation of current IRC
conversation logging systems is that they just record and present what was said
on each channel individually, not taking into account the relations described
above.</p>
        <p>People may also leave and join a channel a number of times a day (i.e., they
may not be always present when conversations take place). Thus, they may need
to re-establish the context of what was happening while they were gone.</p>
        <p>This all motivated us to create SiocLog - a tool that not only records IRC
conversations but also lets users explore relationships that exist on IRC, e.g., to
collect together activities of a person across multiple IRC channels.
3</p>
      </sec>
      <sec id="sec-4-2">
        <title>Design</title>
        <p>The design of the SiocLog system is mainly an application of the Linked Data
principles and technologies as well as the SIOC vocabulary to the domain of
publishing IRC discussion logs. The following subsections describe some of the
central design decisions.
3.1</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Web addresses at SiocLog sites Table 1 summarises the URIs that SiocLog sites provide. SiocLog mentions the corresponding legacy, non-Web URIs as synonyms ( owl:sameAs) for wider compatibility and integration.</title>
      <p>In addition to the conventional navigation links between the pages of a web site,
SiocLog has Linked Data links. You can make queries that take advantage of
these links, and download data by following these links. The meaning of the links
is standardised via well-known vocabularies such as FOAF and SIOC. Figure 2
shows what the SiocLog site looks like initially when opened in a Linked Data
browser.</p>
      <p>Figure 3 describes how the data on the site links to other pieces of data.
The topmost element is a sioc:Space, which represents an IRC network and
which contains the users, channels and their posts. Linking to external Linked
Data happens in two ways: a foaf:Person in a FOAF prole can be linked to
(foaf:holdsAccount ) a user, and a post can link explicitly with a URI to any
Linked Data resource. Similarly, URIs in channel topics could be analysed as
links to the topics.</p>
      <p>The link between a person and a user is valuable in many ways, because the
FOAF prole can contain more links. For example, the foaf:knows links build
an explicit social network between people, and this can now be used to infer
a network and trust between IRC users. Also, the other foaf:holdsAccount
links of a person imply a connection between the IRC user and the person’s user
accounts on other sites. In a simple but useful case, a person in multiple IRC
networks and in multiple installations of SiocLog can be integrated based on
these connections.</p>
      <p>While IRC content is plain text and as such doesn’t express rich semantics, it
would be conceivable to interpret textual markup such as MicroTurtle 11, which
would turn each post into an arbitrary RDF graph. SiocLog would then publish
these graphs along the textual content. An issue here is how to separate the
provenance of the user from the one of SiocLog in a way that the potential data
consumers would support. The traditional Semantic Web solution would be triple
11 http://buzzword.org.uk/2009/microturtle/spec
reication either as specied in RDF or by OWL property chains. We envision
a more web-like solution where the graphs would be published at per-user
subdomains of the SiocLog domain (e.g. at http://wikier.irc.sioc-project.
org/).
3.3</p>
    </sec>
    <sec id="sec-6">
      <title>Web IDs at SiocLog sites</title>
      <p>
        A chat persona can claim a Web ID and thus to be associated with an actual
person. If available, SiocLog uses this information to load and display prole
information, e.g., from a FOAF prole. For example, Figure 4 shows such a
prole about a person (information about the foaf:Person that the Web ID
resolves to). This way, the person doesn’t need to enter data specically for this
site, making use of portability of Social Data [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>One way to claim a Web ID is via mttlbot12, whose results SiocLog uses
as one source of Web ID information. However, mttlbot doesn’t require the
claiming persona to be registered, i.e., it is possible to forge this information.
More importantly, we wanted claiming to be possible using only standard IRC
services.
12 http://buzzword.org.uk/2009/mttlbot/#project
foaf:Person
foaf:holdsAccountfoaf:holdsAccount</p>
      <p>Thus, SiocLog also includes a new way to claim a Web ID: A participant who
has registered their nickname with the IRC network and is logged in ( identied ),
can use the IRC command /msg nickserv set property webid SomeWebID to
set their Web ID. This is a persistent setting, so the participant only needs to
do this once. After this, the Web ID information is publicly available from the
nickserv service as a part of the nickname’s metadata ( taxonomy ).
To verify their Web ID claim, the person behind a chat persona can claim in
the personal prole to be using the specic chat persona. When these claims
point at each other, others can trust that the Web ID is in control of the same
person as the chat persona (see Figure 5). However, people may still as usual
give other false information (real name, photo, friends, etc.) about themselves
in their personal proles.</p>
      <sec id="sec-6-1">
        <title>4 Implementation</title>
        <p>The SiocLog software currently comprises circa 2000 source lines of code (SLOC)
in Python and circa 1000 lines of (unabstracted) HTML page templates in the
Zope Template Attribute Language (TAL). The only external dependencies are
the software libraries Twisted 13 for network IO, SimpleTAL 14 for HTML
template expansion, and Redland 15 for loading and querying Linked Data.</p>
        <p>The architecture of the SiocLog software comprises four major components:
the IRC interface, the data analysis, the data integration, and the Web interface.
13 http://twistedmatrix.com/
14 http://www.owlfish.com/software/simpleTAL
15 http://librdf.org/
4.1</p>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>IRC interface</title>
      <p>The responsibility of the IRC interface is to gather information and log it for
later analysis. Because of the diering requirements, this component is split into
two separate IRC bot programs. One needs to be reliable and thus preferably
stable and simple, mostly passive discussion logger. The other needs to gather
information about the chat personas from the nickname service, responding to
queries from the other components.</p>
      <p>To provide maximum information and exibility for later data analysis,
everything is logged in a text le as timestamped but otherwise raw lines of IRC
protocol. The bots have been built specically for SiocLog and on top of the
Twisted network IO framework. As an alternative or in addition to the bots, log
les could be imported from other systems.
4.2</p>
    </sec>
    <sec id="sec-8">
      <title>Data analysis</title>
      <p>The data analysis processes the raw IRC log les, selecting the relevant events,
analysing their textual content and relation to other events in context,
translating them to the SIOC model, and calculating statistics.</p>
      <p>As IRC data is highly linear in nature, the data analysis is implemented as
a pipeline of lters that process the events and as sinks that format the output.
The rst lters remove o-the-record messages and detect whether the message
is from an authenticated user. Later lters select events that pertain to a specic
channel, user, or time period, and analyse the textual content to extract links.
The sinks aggregate statistics and produce a HTML, RDF, or raw representation
of the events.
4.3</p>
    </sec>
    <sec id="sec-9">
      <title>Data integration</title>
      <p>The data integration queries the Web for information needed to combine the IRC
log data with other Linked Data. It fetches and combines mttlbot’s knowledge16
of nickname to Web ID mappings with SiocLog’s own information. It also fetches
data pointed to by the Web IDs, combines it with SiocLog’s knowledge about
chat personas, and renders the personal proles.</p>
      <p>Currently, this all is implemented as simple queries to temporary in-memory
triple stores.
4.4</p>
    </sec>
    <sec id="sec-10">
      <title>Web interface</title>
      <p>Accepting HTTP requests via the CGI interface of a Web server, the Web
interface depends on the data analysis and integration parts and publishes the results
as Web pages in HTML and as Linked Data documents in RDF. This component
does HTTP content negotiation, splits requested URIs into query parameters,
drives the data analysis and integration tasks, as well as translates the results
to the output format.
16 http://buzzword.org.uk/2009/mttlbot/graphs/knowledge</p>
      <p>Listing 1.1. Example SPARQL query over IRC data provided by SiocLog.
semwebquery s p a r q l "SELECT ?name WHERE {
? p e r s o n f o a f : holdsAccount</p>
      <p>&lt;http : / / i r c . s i o c p r o j e c t . org / u s e r s / m e l v s t e r#user &gt; .
? p e r s o n f o a f : knows ? f r i e n d .</p>
      <p>? f r i e n d f o a f : name ?name . }"
5</p>
      <sec id="sec-10-1">
        <title>Validation</title>
        <p>An installation of the software is in use on a few Linked Data related IRC
channels since 118 days as of writing. Based on this experience, it has been reliable,
and it has been convenient to be able to constantly improve the analysis,
integration, and publishing parts on the y. It has collected discussions of 291 chat
personas on 5 channels this far, 22418 messages in total. For 51 chat personas
in total, it knows the Web ID of the person behind them (41 from mttlbot, 18
set at nickserv; 52% of #sioc personas, 15% of #swig personas). Of these 51
Web IDs, 44 point to a valid RDF document which SiocLog is able to render
reasonably. This far, 7 people have conrmed their Web ID claim in their FOAF
prole.</p>
        <p>
          To test browsability, we checked that given the site root URI, a Linked Data
browser such as Fenre [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ] manages to browse all the Linked Data as published
by the SiocLog installation. Further, the Semantic Web Client Library 17 gives
prompt and correct results for some purely declarative SPARQL queries, for
example, names of the friends of the IRC persona melvster in Listing 1.1.
        </p>
        <p>The project Towards linked sensor data for Hackystat 18 is already at this
phase consuming Linked Data from SiocLog to track the discussion activity of
software developers.</p>
        <p>FOAF Me19 provides some simple integration with SiocLog. If a user doesn’t
have a FOAF prole, SiocLog links to FOAF Me as a possible service for
authoring one. FOAF Me will detect the linking and automatically pre-ll the prole
with the respective IRC user as a nick name and as an external account. The
FOAF Me project has further plans to consume the data from a SiocLog account
in an activity feed view of the person.
5.1</p>
      </sec>
    </sec>
    <sec id="sec-11">
      <title>Scalability</title>
      <p>For the rst two months of discussions on #swig logged by SiocLog, there were
191 participants, and 10948 messages with 662567 bytes of textual content. This
is 1.6 megabytes of the raw text log format, or 5.3 megabytes of Turtle RDF
format, or 3.2 megabytes of HTML web pages.
17 http://www4.wiwiss.fu-berlin.de/bizer/ng4j/semwebclient/
18 http://socghop.appspot.com/student_project/show/google/gsoc2009/
hackystat/t124022455248
19 http://foaf.me/</p>
      <p>The current representation produces 5 RDF triples per user, 7 triples per
channel, and 6 triples plus any enrichment per post. In total, these form 67192
triples. Assuming that the activity of the channel remains similar, a linear
extrapolation predicts this would become 4 million triples in 10 years, which is not
a challenge for modern RDF stores.
6</p>
      <sec id="sec-11-1">
        <title>Related work</title>
        <p>Dave Beckett’s Logger 20 IRC bot has been publishing IRC discussion logs in
RDF since year 2001. However, the output from Logger is somewhat outdated
regarding Linked Data principles as it doesn’t give the participants http URIs
and corresponding information documents with links to more information, and
it uses the old RDF container properties instead of SiocLog’s implicit ordering
of events based on dc:date. Further, Logger doesn’t use the standard and rich
SIOC (Semantically-Interlinked Online Communities) vocabulary in its RDF.
Finally, Logger doesn’t let chat participants declare their Web ID and thus doesn’t
link out to and integrate with FOAF network of people or the larger Web of Data
in general.</p>
        <p>
          Another application that converts non-Web social data to Linked Data is
SWAML [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ], which converts mailing list archives. Like SiocLog, SWAML can
establish a link between the sender and their Web ID. As e-mail messages
already unambiguously identify via sender address the person sending the message,
SWAML can look up the Web ID in a search engine.
        </p>
        <p>
          Another application that publishes small messages as Linked Data using
the SIOC vocabulary is SMOB [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ], which is a semantic microblogging system.
Still, microblog posts are somewhat longer and more self-contained than IRC
messages, so they are more like ordinary documents.
7
        </p>
      </sec>
      <sec id="sec-11-2">
        <title>Conclusion</title>
        <p>This paper introduced SiocLogan application for collecting IRC conversations,
making them available for reuse in other applications and services via the use
of Linked Data, and for enabling rich access to knowledge contained in these
conversations.</p>
        <p>We described how SiocLog links together users and channels on which users
engage in conversations. It can also bring in and integrate Linked Data from
external sources, e.g., people’s FOAF proles.</p>
        <p>While SiocLog as implemented deals exclusively with IRC content, a system
supporting other instant messaging systems should be similar. The idiosyncrasies
of each system will aect the best way to form URIs. The exact way of observing
discussions will depend on the system, as protocols and chat culture vary. For
example, where private chats are the norm, participants will need either to invite
an observer bot, or to collect and publish the events themselves. There will also
20 http://www.dajobe.org/software/logger/
be dierences in the exact form of discussions, such as whether channels have
topics or only names.</p>
        <p>This work envisions SiocLog as a signicant part of the Web of Data, acting
as an initial consumer and use case of FOAF data as well as providing other
applications with real-time services such as user presence data or information
about resources that people talk about right now. Further, by publishing rich,
structured information about IRC conversations, SiocLog can help new
studies of online communities and their behaviour to include data about real-time
communication.
8</p>
      </sec>
      <sec id="sec-11-3">
        <title>Acknowledgements</title>
        <p>The authors would like to thank Benja Fallenstein and Dan Brickley for their
insights on the requirements and suitable technologies for SiocLog.</p>
      </sec>
    </sec>
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