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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>On Agent-
Mediated Electronic Commerce. IEEE Transactions on
Knowledge and Data Engineering.</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>A Multi-Agent System for Content Trading in Electronic Telecom Markets Using Multi-Attribute Auctions</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Ana Petric Faculty of Electrical Engineering and Computing, University of Zagreb Unska 3</institution>
          ,
          <addr-line>Zagreb</addr-line>
          ,
          <country country="HR">Croatia</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>[18] V. Podobnik, I. Lovrek, “Multi-Agent System for Automation of B2C Processes in the Future Internet”, Student Workshop @ 27th IEEE Infocom</institution>
          ,
          <addr-line>Phoenix, USA, in Press</addr-line>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2008</year>
      </pub-date>
      <volume>15</volume>
      <issue>4</issue>
      <fpage>735</fpage>
      <lpage>737</lpage>
      <abstract>
        <p>The advent of the Internet and the development of the New Generation Network (NGN) has enabled, while investments in licenses and the desire to stay competitive in the future has triggered the development of value added services (VAS). Due to high market penetration, the telecommunication industry has been facing income stagnation. Consequently, it has been shifting focus to VAS in order to increase income. When forming VAS, special attention needs to be paid to the purchase of resources (e.g., transport capacity and information resources) needed for the service creation. The fact that information resources (i.e., content) are not commodities, opens the question of what is the best (i.e., efficient) mechanism that should be used for trading. As the number of participants on the B2B telecom market increases, the need for the automation of transactions carried between them is critical. The automation of transactions should lower operational costs and speed up the service provisioning process. In this paper, we try to identify stakeholders on the telecom e-market, establish their roles and relationships and find an appropriate model which captures their transactions. Finally we consider the use of multiattribute auctions for content trading in telecom markets.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Multi-attribute auctions</kwd>
        <kwd>Multimedia Content Trading</kwd>
        <kwd>B2B emarkets</kwd>
        <kwd>Intelligent Software agents</kwd>
        <kwd>New Generation Network</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. INTRODUCTION</title>
      <p>The advent of the Internet and the development of the New
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10th Int. Conf. on Electronic Commerce (ICEC) ’08 Innsbruck, Austria
Copyright 2008 ACM 978-1-60558-075-3/08/08 ...$5.00.</p>
      <p>
        Generation Network (NGN) provide connections which enable a
particular lifestyle that is aspiring to digital humanism where
people’s daily activities are becoming more digitalized,
convenient and intelligent [
        <xref ref-type="bibr" rid="ref19">27</xref>
        ]. Actors on the telecom markets are
pursuing innovations and launching new value-added services
(VAS) [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] in order to increase revenue. This is due to the fact that
provisioning basic telecommunication services (i.e., fixed and
mobile communication, data transfer) is no longer enough to keep
existing customers, let alone attract new ones, due to high market
penetration. Investment regain of licenses and staying competitive
in the future are key drivers for the expansion of new VAS on the
market. This new market demand and technological development
has led to the convergence of different domains (i.e.,
telecommunications, information technology (IT), the Internet,
broadcasting and media) all involved in the telecom service
provisioning process. The ability to transfer information
embodied in different media into digital form to be deployed
across multiple technologies is considered to be the most
fundamental enabler of convergence [14]. An important feature of
convergence is the composition of services and content derived by
combining multiple simpler services or types of content in order
to provide more powerful services.
      </p>
      <p>The research problem addressed in this paper concerns the
automation of business processes related to the creation of VAS
that are traded on the telecommunication electronic markets
(emarkets). There are two types of resources needed for the creation
of telecom VAS. They are the information resources (i.e., content)
the service is based on and the transport capacities needed for
service provisioning. The telecom market is divided into two
submarkets, the B2B (Business-to-Business) market and the B2C
(Business-to-Consumer) market. Our research is focused on B2B
telecom e-market trading with information resources using
multiattribute auctions.</p>
      <p>The rest of the paper is structured as follows. Section 2 describes
the participants on the telecom e-market. Section 3 describes the
phases we need to go through in order to conduct a transaction on
the B2B telecom e-market. Section 4 addresses general auction
mechanisms and presents multi-attribute auctions. Section 5 states
the main questions of this research effort and proposes some
answers.</p>
    </sec>
    <sec id="sec-2">
      <title>2. TELECOM E-MARKETS</title>
      <p>
        The appearance of new stakeholders on the B2B telecom market
had to be taken into account so new business models were
formed. One of the long-term objectives of the NGN is to support
business models that open the market to emerging service
providers [14]. The volume and dynamic nature of VAS offered
in the NGN place novel demands and challenges on telecom
stakeholders. In this newly developed situation it is not enough
just to adequately respond on the existing requests but also to
intelligently anticipate the development of the future events and
adapt to their environment. In order to understand the
relationships between stakeholders and the way they interact it is
important that their roles are well classified. We use the
classification determined in [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] as shown in Figure 1.
Consumers are service users that have at their disposal various
devices (e.g., mobile phone, laptop, PDA) and are connected
through various access networks (e.g., 3G, WiMax). Access
Provider ensures telecommunication access for service
consumers. Service Provider facilitates a variety of basic and
integrated services for consumers enabling easy content
consumption. Carriers provide a transport service for the data
traffic and they usually buy bandwidth from Network
Infrastructure Owners who provide transmission lines. A large
number of Carriers are at the same time also Network
Infrastructure Owners. Wholesaler of Capacity provides
lowercost transmission and storage capacity. Content Owner possesses
the information in its original format while Content Enabler
converts this information to a format eligible for the transmission
over heterogeneous networks. Content Provider is at the same
time Content Owner and Content Enabler. Wholesaler of Content
provides lower-cost content. Server Infrastructure Owner
provides storage capacity and server functionality. Information
Enablers enable information resources while Transport Enablers
provide transport of information resources through the various
networks swiftly and seamlessly.
      </p>
      <p>We are focusing on the B2B e-market since it is widely believed
that it will become the primer way of doing business [21]. The
assumption is that the telecom B2B e-market will grow with other
B2B e-markets. A special intention is paid to the negotiation
phase since the outcome (i.e. financial efficiency) is still the
premier performance measure for most businesses [16, 17].
n</p>
      <p>USE
n
n
n</p>
      <p>FACILITATE
n</p>
      <p>n
STORE &amp;
ENABLE
n
TRANSPORT</p>
      <p>n
Content Owner
Content Enabler</p>
      <sec id="sec-2-1">
        <title>Server Infrastructure n</title>
        <p>Owner
Wholesaler of Content n
n
n
Carrier
n</p>
      </sec>
      <sec id="sec-2-2">
        <title>Network Infrastrucutre n</title>
        <p>Owner
Wholesaler of Capacity n</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. B2B TELECOM E-MARKET</title>
      <p>
        The BBT (Business-to-Business Transaction) model [15]
systematically analyses processes in B2B e-markets. The
proliferation of auctions on the Internet, and the dynamic nature
of auction interactions, argues for the development of intelligent
trading agents which act on behalf of human traders (i.e., buyers
and sellers). Intelligent trading agents can also be used to
impersonate stakeholders in the environment of the NGN in order
to enable automated interactions and business transactions on the
telecom markets [20]. Namely, an agent can monitor and
participate in the market continuously. Software agents [
        <xref ref-type="bibr" rid="ref7">7, 19</xref>
        ] are
programs which autonomously act on behalf of their principal
while carrying out complex information and communication tasks
that have been delegated to them. A software agent is intelligent
(its intelligence is grounded on its knowledge base, reasoning
mechanisms and learning capabilities), autonomous, reactive,
proactive, cooperative, and persistent. Additionally, a software
agent can also be mobile.
      </p>
      <p>From the BBT model perspective [15], we can formally identify
six fundamental steps which must be executed in order to
successfully complete one transaction in a B2B environment.
These steps are as follows (Figure 2): 1) partnership formation, 2)
brokering, 3) negotiation, 4) contract formation, 5) contract
fulfillment, and 6) service and evaluation. B2B negotiation is
complex since it typically involves larger volumes, repeated
transactions and more complicated contracts. This is the reason
why most researchers have concentrated on the negotiating phase
of B2B market transactions.</p>
      <p>
        The partnership formation phase usually includes forming of a
new virtual enterprise or finding partners to form a supply chain.
A virtual enterprise represents a form of cooperation of
independent stakeholders which combine their competencies in
order to provide a service [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. On the B2B telecom e-market,
Content Owners, Content Enablers, Server Infrastructure Owners
and Wholesalers of Content can form a virtual enterprise in order
to successfully place and sell information resources to various
service providers. Moreover, Carriers, Network Infrastructure
Owners and Wholesalers of Capacity may also form a Virtual
Enterprise to enhance trading with transport capacity. With the
expansion of the e-market, the number of buyers and sellers
grows accordingly making it more difficult to find all potential
business partners trading a requested service/resource. The main
role of the Brokering phase is to match service providers with
information/transport enablers that sell information
resources/transport capacities needed for the creation of a new
service or improvements of an old one.
      </p>
      <p>Negotiation is a process which tries to reach an agreement
regarding one or more resource attributes (e.g., price, quality,
etc.). Each stakeholder in the negotiation process is represented
by an intelligent trading agent that negotiates in his behalf (e.g.,
Information Agent trades in behalf of Information Enabler). The
trading agent uses a negotiation strategy suitable for the type of
auction applied (i.e., negotiation protocol) on the market. The
negotiation protocol defines the rules of encounter between
trading agents. It should ensure that the negotiation’s likely
outcome satisfies certain social objectives, such as maximizing
allocation efficiency (i.e., ensuring that resources are awarded to
the participants who value them the most) and achieving market
Procurament auctions
(Multi‐attribute Auction)
Double‐sided auctions
(Continuous Double</p>
      <p>Auction ‐ CDA)</p>
      <p>NEGOTIATION</p>
      <p>CONTRACT
FORMATION</p>
      <p>BROKERING
CONTRACT
FULFILLMENT</p>
      <p>PARTNERSHIP</p>
      <p>FORMATION
BBT model
SERVICE AND
EVALUATION</p>
      <p>Virtual enterprise – Information enabler</p>
      <p>Content Owner</p>
      <p>Content Enabler
Server Infrastructure</p>
      <p>Owner
Wholesaler of</p>
      <p>Content
Virtual enterprise – Transport enabler</p>
      <p>Carrier</p>
      <p>Network
Infrastructure Owner</p>
      <p>Wholesaler of</p>
      <p>
        Capacity
equilibrium [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. The negotiation strategy represents a set of rules
that determines the behavior of a trading agent.
      </p>
      <p>
        The negotiation process can be either distributive or integrative
[
        <xref ref-type="bibr" rid="ref14">22</xref>
        ]. In distributive negotiations, one issue is subject to
negotiation while the parties involved have opposing interests.
One party tries to minimize loss and the other party tries to
maximize gain. Distributive negotiations are also characterized as
“win-lose” negotiations. The continuous double auction (CDA),
which is suitable for transport capacity trading in a B2B e-market,
represents a distributive type of negotiation in a multi-unit auction
with multiple buyers and sellers [
        <xref ref-type="bibr" rid="ref17">25</xref>
        ].
      </p>
      <p>In integrative negotiations, multiple issues are negotiated while
the parties involved have different preferences towards these
issues. For example, two information enablers may want to sell
multimedia information resources to a portal provider, but one is
primarily interested in the sale of news, whereas the other is
interested in the sale of movie clips. These variant valuations can
be exploited to find an agreement resulting in mutual gain. If their
preferences are the same across multiple issues, the negotiation
remains integrative until opposing interests are identified. In such
a case, both parties can realize gains: consequently, another name
for this class of negotiations is “win-win” negotiations. A
multiattribute auction represents an integrative negotiation process
which can be used for trading with information resources.
Last three phases include termination of negotiation where
negotiated terms are put in a legally binding contract (contract
formation), carrying out the transaction agreed in the contract
(contract fulfilment) and traders evaluating the received service
(service evaluation). Due to legal issues and subjective judgments
it is not likely that these phases are going to be automated with
the use of intelligent agents.</p>
    </sec>
    <sec id="sec-4">
      <title>4. AUCTIONS</title>
      <p>
        Auctions, due to their well defined protocols, are suitable enablers
of negotiations in e-markets. The variety and value of goods that
are sold in auctions has grown to tremendous proportions.
Auctions are defined as a market institution that acts in pursuit of
a set of predefined rules in order to compute the desired economic
outcome (i.e., high allocation efficiency) of social interactions
[
        <xref ref-type="bibr" rid="ref18">26</xref>
        ]. Based on bids and asks placed by market participants,
resource allocation and prices are determined. There are two main
directions to take when designing auctions, namely we distinguish
efficient and optimal auctions. The objective in efficient auctions
is to maximize allocative efficiency and deal with dividing the
surplus in an auction among the auctioneer and bidders, while
optimal auctions concentrate on maximizing revenue or the
expected utility of the bid taker [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
    </sec>
    <sec id="sec-5">
      <title>4.1 Multi-attribute auctions</title>
      <p>
        Item characteristics (i.e., attributes) represent an important factor
in deciding which auction should be used in the negotiation phase.
Negotiation on commodities, such as transport capacities, focuses
mainly on the price of the item. These items are mostly sold in
conventional single-attribute auctions. On the other hand,
complex items such as information resources often require
negotiation of several attributes, and not just the price [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. They
are sold in multi-attribute auctions [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] which are a special case of
procurement auctions. Procurement auctions are also called
reverse auctions since there are multiple sellers (e.g., information
enablers) and only one buyer (e.g., service provider) that
purchases items (e.g., information resources). Multi-attribute
auctions have been attracting more and more attention in B2B
markets since the price is not the only important attribute
considered in the decision making process1.
      </p>
      <p>
        The first step in a multi-attribute auction is for the buyer to
specify his preferences regarding the item he wishes to purchase.
Preferences are usually defined in the form of a scoring function
based on the buyer’s utility function [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. In order to familiarize
sellers with buyer’s valuations of relevant attributes, the buyer
usually publicly announces his scoring function. Sellers are not
obligated to disclose their private values of an item. The winner
of the multi-attribute auction is the seller that provided the highest
overall utility for the buyer. The buyer sends a request to all
interested sellers which than reply by sending bids. The buyer
selects the bid with the highest overall utility. If the auction is
one-shot, this bid is declared the winning one, otherwise it is
declared as the currently leading bid and the new round of the
auction begins. The buyer can also define the bid increment or
minimum requirements the bid has to fulfill in order to compete in
the next round. Figure 3 shows a multi-attribute auction between a
service provider and several information enablers. Information
enablers offer multimedia content composed of video and audio
streams with different performances. Based on its utility function,
the service provider reaches an agreement with the information
enabler whose information resource has the highest overall utility.
      </p>
    </sec>
    <sec id="sec-6">
      <title>4.2 Content trading</title>
      <p>
        The term content encompasses movies, songs, news, images and
text, in other words data and information within various fields
[
        <xref ref-type="bibr" rid="ref15">14, 23</xref>
        ]. The NGN brings its own new added value into the
market and one of these added values is multimedia content
composed of several types of content (e.g., audio, video, data…)
1
      </p>
      <p>http://www.cindywaxer.com/viewArticle.aspx?artID=149
(Business 2.0 magazine)</p>
      <p>Business
INFORMATION AGENT</p>
      <p>(SELLER ROLE)
INFORMATION</p>
      <p>ENABLER
(SELLER #2)</p>
      <p>Business
INFORMATION AGENT</p>
      <p>(SELLER ROLE)
INFORMATION</p>
      <p>ENABLER
(SELLER #5)</p>
      <p>
        Business
INFORMATION AGENT
(SELLER ROLE)
[
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. When trading with multimedia content there are several
attributes that are negotiated on; the quality of the audio and
video content (i.e., audio bit rate, resolution of the video), type of
the information provided (i.e., music, video clips, games, news,
sports, weather…), time of origin of the content (e.g., two days
old weather forecast is of no use, one minute old stock market
news could be worth a lot), reusability of the content (i.e., using
the content in forming various services), potential number of users
interested in this content, and the price. An example of trading
with multimedia content by using multi-attribute auctions is
shown in Figure 3 where several agents posing as sellers offer
different multimedia (i.e., audio and video) content while the
agent posing as a buyer must decide which content holds the
highest utility for him and then buy the content in order to resell it
further on the B2C e-market [18].
      </p>
    </sec>
    <sec id="sec-7">
      <title>5. PROPOSAL OF THE RESEARCH PLAN</title>
      <p>The research plan consists of four stages2. The aim of the first
phase is to explore the telecom market, identify participants on
the market, establish their roles and relationships, and, finally
establish with what goods and services are being traded on the
market. This phase is completed and is described in Section 2. We
can se that a service provider actually manages a supply chain by
buying information and transport capacities on the B2B telecom
2 I am a 3rd year PhD student.
e-market, forming value added services from purchased goods
and then selling those services to consumers on the B2C telecom
e-market.</p>
      <p>
        Due to the lack of research related to B2B telecom e-markets [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]
(i.e., most research is related to the B2C telecom e-market [
        <xref ref-type="bibr" rid="ref10 ref12 ref5">5, 10,
12, 18</xref>
        ]) and the expected growth of B2B e-markets in general, the
second phase is oriented to finding an appropriate model which
captures all stages related to transactions carried out on the B2B
telecom e-market. As shown in Section 3, the BBT model was
used to describe B2B telecom transactions, while intelligent
agents were used to impersonate stakeholders on the market.
Since the B2B e-market includes repeated transactions with
existing and/or new business partners, a new phase should be
introduced into the BBT model. This phase will be in charge of
collecting knowledge regarding the state of the e-market,
processing information collected in the service evaluation phase,
and deciding on the changes that need to be applied in the next
round of negotiations.
      </p>
      <p>
        The third phase is dedicated to the negotiation phase of the BBT
telecom model. Well defined and widely researched CDA is used
for trading with transport capacities. Consequently, we decided to
focus on multi-attribute auctions for trading with information
resources (i.e., content). In order to trade with content, the first
step is to define relevant attributes and form an ontology which
adequately represents multimedia content. The next step is to
study existing models of multi-attribute auctions using different
approaches (i.e., defining utility functions [
        <xref ref-type="bibr" rid="ref2 ref3">2, 3</xref>
        ], fuzzy
multiattribute decision making algorithms [
        <xref ref-type="bibr" rid="ref16">24</xref>
        ], introducing pricing
functions and preference relations for determining acceptable
offers [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], defining reserved and aspiration levels of attributes
and distinguishing negotiable and non-negotiable attributes [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]).
After studying the existing models, we plan to choose the best
features from each approach and try to incorporate them into a
new unified model most suitable for content trading. The new
approach will be incorporated into to the multi-attribute auction
mechanism based on the English auction. Due to the specifics of
the B2B telecom e-market (e.g., larger values of single
transactions, repeated transactions, and a smaller number of
participants than on B2C e-markets) the goal is to create a balance
between maximizing the allocative efficiency of the B2B market
and maximizing revenue or the expected utility of bid takers
characteristic for multi-attribute auctions.
      </p>
      <p>The fourth phase will be devoted to implementing the
multiattribute auction with agents as representatives of telecom
stakeholders using the JADE (Java Agent DEvelopment
Framework) agent platform and evaluating the designed
mechanism with the existing mechanisms mentioned in the
previous paragraph.</p>
    </sec>
    <sec id="sec-8">
      <title>6. ACKNOWLEDGMENTS</title>
      <p>The work presented in this paper was carried out within research
projects 036-0362027-1639 "Content Delivery and Mobility of
Users and Services in New Generation Networks", supported by
the Ministry of Science, Education and Sports of the Republic of
Croatia, and "Agent-based Service &amp; Telecom Operations
Management", supported by Ericsson Nikola Tesla, Croatia.</p>
    </sec>
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