AN ANALYSIS OF CONTEXT-AWARENESS
IN COMMERCIAL MOBILE SERVICES
Ana M. Bernardos, Daniel Marcos and José R. Casar
ETSI Telecomunicación, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
Keywords: Mobile data services, context-aware applications, location based services, mobile business.
Abstract: This contribution aims at analyzing context-awareness from a commercial point of view, studying how the
utilization of context descriptors and features in mobile services has evolved during the period 2003-2008.
The analysis is based on the information collected during a Technology Watch activity; this methodology
has provided us with a large database of mobile services, built from monthly updates of mobile novelties
and commercial launches. Services in the database have firstly been categorized regarding their
functionalities, in order to get the big picture of the mobile ecosystem in this period of time. Afterwards, we
have identified a list of descriptors (personal, physical or activity related) and features (related to resources
discovery, management and communications and also to advances HCIs) which are usually identified in
context-aware applications and systems prototypes. The use of these descriptors and features has been
evaluated for each service and some trends have been detected. Our general conclusion is that nowadays
few commercial mobile services can be considered “context-aware”, although isolated features (mainly
related to personalization) are perceived in many applications. Due to their functionalities, location aware
services and mobile social networks are leading the use of context parameters.
1 INTRODUCTION
Simultaneously with the evolution of commercial
mobile technologies and markets, a lot of research
has focused on bringing to reality the paradigms that
are supposed to sketch the future of mobility (Mohr,
2008). Ubiquitous and pervasive computing (Weiser
et al., 1999) inspire the concept of ambient
intelligence (ISTAG, 2001), a smart and sensitive
scenario where context-aware applications
(personalized and status adaptive services) make
easier everyday activities (Schilit and Theimer,
1994).
To date, context-awareness has inspired many
research prototypes in different application fields
(museums, airports, hospitals, smart homes, etc., see
Section 2). From an analysis on the evolution of
commercial mobile services during 2003-2008, this
contribution aims at shedding some light on how
context-aware research concepts and features are
being transferred into market applications. Our final
motivation is to identify the hindrances (technical,
privacy and business related issues) which need to
be overcome to generalize the use of context
information in commercial mobile services.
It is important to remark that this is neither a
forecasting work nor a study on adoption and pattern
of use study on mobile services. Both types of
analysis are already common in (academic and
corporate) literature. With respect to forecasting,
there are some broad-scope proposals that aim at
predicting the penetration and the traffic in cellular
mobile networks –eg. (Arvidsson et al., 2007)- and
also studies focused on niche services or particular
markets –eg. (Funk, 2007). On the other hand,
mobile services adoption is attracting great interest:
for example, Kelleher (2007) analyzes four studies
on this issue, Bouwman et al. (2006) goes deeper on
barriers and drives that condition the services’ use
and Bina and Giaglis (2005) and Gilbert and Han
(2005) analyze users’ preferences taking into
account their life styles, needs and demographical
characteristics. Verkasalo (2007) studies the users’
preferences from the analysis of the data traffic
generation of a group of representative applications.
Using a complementary perspective to mobile
data adoption studies, our contribution is firstly
conceived to analyze the generation of mobile
services. With this purpose, during the last five years
(2003-2008), we have followed a Technology Watch
methodology which has provided us with a monthly
updated data base of new mobile services. In this
contribution, we elaborate on the long series of
177
M. Bernardos A., Marcos D. and R. Casar J. (2008).
AN ANALYSIS OF CONTEXT-AWARENESS IN COMMERCIAL MOBILE SERVICES.
In Proceedings of the International Conference on e-Business, pages 177-184
DOI: 10.5220/0001910801770184
Copyright
c
SciTePress
gathered data in order to show how mobile services
and context-awareness presence has evolved.
The paper is organized as follows. Section 2
goes deeply into the concept of ‘context-awareness’
and gathers a review of its areas of application.
Section 3 presents the methodological approach used
in this study. From the empirical analysis, Section 4
provides a view of the mobile ecosystem, to frame
Section 5, which elaborates on the level of “context-
awareness” that current mobile applications have.
Section 6 concludes the paper with some open issues
for the generalization of context-awareness in
commercial mobile services.
2 FROM LOCATION BASED
SERVICES TO
CONTEXT-AWARE
APPLICATIONS
From the late nineties on, location has been the
enabler of a number of commercial “precontext-
aware” services, such as family finders, location
based advertising, area billing, pervasive games,
trackers, real time location systems (RTLS), etc.
(Bernardos et al., 2007). After a complicated take off
of LBS (Kaasinen, 2002), standalone navigation and
tracking applications have nowadays become
popular, partly due to some device manufacturers’
efforts to promote the use of GPS enabled devices.
Meanwhile, innovative mobile services related to
Web 2.0 have shown up (it is the case of mobile
social software or applications making easier content
geotagging, for example) and some analysts expect
them to contribute to widen the adoption of LBS.
Simultaneously to LBS evolution, research in
context-aware systems and services has gone ahead.
Since the pioneers Active Badge or PARCTab
projects, advances and challenges in positioning
techniques, semantic context representations or
software architectures for context-awareness have
evolved and a great variety of application
environments have been explored. By way of
illustration, following there is a short list of some of
them:
- Context-aware mobile guides: many initiatives
(such as the breaking Cyberguide or GUIDE)
have focused on the development of tourist
context-aware mobile guides. Museums (e.g.
Sotto Voce or Exploratorium projects) and
exhibition centres (e.g. Hippie prototype,
mExpress project or XGuide application) have
also been inspiring environments. Augmented
reality techniques are nowadays being
combined with context-awareness to achieve a
new user experience.
- Productivity applications for working spaces
such as classes, campuses (e.g. ActiveCampus,
Classroom 2000 or eClass projects) and offices
(e.g. Context-Aware Office Assistant).
- Fieldwork applications for environments where
recording and filtering data are prior tasks, such
as laboratories (e.g. Labscape) or archaeology
areas (e.g. the Context-aware Archaeological
Assistant).
- Smart homes are highly pervasive scenarios
with sensors, actuators, wireless networks, etc.
(Meyer and Rakotonirainy, 2003); in particular,
there is a growing interest in applications aimed
at supporting daily living activities and well-
being (especially of elderly and disabled people)
(e.g. Wireless Wellness Monitoring and Howel
projects).
- Health care environments, such as hospitals -
Bricon-Souf and Newman (2007) contains a
survey- or even operating rooms (Agarwal et
al., 2007).
- Horizontal applications such as memory aids,
location annotation software (e.g. GeoNotes) or
context-aware telephony (callers are provided
with context information about the receivers
(Khalil and Connelly, 2006)).
- Other challenging areas of application are
context-aware mobile learning (e.g. Mobilearn
project), context-aware mission critical support
(e.g. Siren project for firefighting) or ubiquitous
mobile gaming (e.g. Botfighters).
Context-aware services share requirements with
general mobile ones (eg. with respect to usability
and interaction mechanisms, device requirements -
screen sizes or power consumption-, network speed,
etc) but, the same as location based services, are
especially dependant on:
1) Stable location mechanisms. Location is a
relevant descriptor of context that is used as a filter
in most context-aware applications. The quality of
the location estimation has a direct impact on the
user experience. So, reliable, transparent and
latency-controlled location mechanisms are still
needed to offer an acceptable user experience. To
date, GPS (and its variants, such as A-GPS) is the
most used positioning mechanism outdoors. But
GPS does not perform well indoors, where the
multiplicity of networks make possible to configure
diverse solutions. Roaming among different
positioning technologies is a challenge to be solved.
2) Reliable privacy management. Context-
awareness means acquiring and handling identity,
real time location or activity data. Users must be
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178
aware of which personal data are being managed and
have control over the acquisition mechanisms. The
combination of security, pseudonym use or cloaking
zones may confer the user with a sufficient feeling
of control.
3) Sustainable business models: clarifying the
“ownership” of context data. Mobile operators are
nowadays handling a lot of personal information
(such as rough cell-based location data) and
providing third partners with the tools to access it.
At the same time, hardware manufacturers are
equipping mobile device with autonomous sensors
(eg. GPS or NFC readers), capable of acquiring
context information directly from the device. Some
of them are also partially shifting their revenue
sources to the provision of applications that use the
acquired parameters. These two different approaches
to context-data acquisition may determine the
development of context-aware services.
“Fully-compliant” context-aware applications
seem to be in a prototype stage yet. But some mobile
services are already intensively using some context
descriptors. In the next pages, we intend to analyze
to which extent context-awareness is implemented in
current commercial mobile services and how it has
evolved in the last few years.
3 METHODOLOGICAL
APPROACH
Technology Watch, according to the Standard UNE
166006-EX, is the continuous process of obtaining
and selecting information from a scientific and
technological environment, in order to turn it into
useful knowledge by analyzing and spreading it, so
that organizations can take advantage of it and make
better decisions by being ahead of changes.
From 2003 to date, a Centre for Technology
Diffusion in the UPM, CEDITEC, accomplishes a
Technology Watch Programme in ‘Wireless
Technologies and Mobile Applications’, which
includes the generation of a monthly newsletter and
a technology watch report on this issue. The watch
process starts with the selection of critical
information sources related to mobility, more than
60 sources ranging from technical publications to
mobile market focused weblogs, also including
general press. Afterwards, a methodical process of
data collection allows expert filtering to elaborate a
selection of the most relevant information in the
month: news, reports, publications, patents, products
and also an average selection of the 15 newest and
most representative mobile services found in that
period of time.
This way, our time-indexed database gathers
information of 735 mobile services, from May 2003
to March 2008. As the technology watch process has
not been to collect every new service, but the most
representative or new, the quantitative analysis
happens to be done on critically filtered data.
Besides, the services are mainly focused on
European and North America markets (as it is
difficult to directly access Asian information
sources, due to language restrictions).
In this contribution, the services’ information has
been submitted to further analysis, considering the
aspects of user experience, technology evolution,
business case, and contextual functionalities
developed in the following sections.
4 BUILDING THE BIG PICTURE
OF THE EVOLUTION OF
MOBILE SERVICES
In this section, we comment on the mobile
ecosystem evolution between 2003 and 2008, the
considered period of analysis. The objective is to
provide the reader with a general (not complete)
picture on how the situation has changed in the last
five years, supporting our statements with some
results of the analysis of the collected data.
a) Entertainment and self content generation
together with information services has driven the
production of mobile applications.
To analyze what the present offer of mobile services
is and how it has evolved during the last five years,
we have inferred a functional classification on the
stored data. It is composed of 12 categories; we
consider that a potential category becomes a formal
one when it groups 20 services as a minimum. The
classification is as follows (note that some services
may match more than one category):
- Location and tracking: of people or mobile
assets (94 services).
- Information: news, weather reports, etc. in
addition to eLearning and language translation
services (130).
- m-commerce: mobile payments, financial
services and m-ticketing (62).
- Browsing and searching: in the Internet (41).
- Connectivity and communications: including
VoIP, SMS, MMS, IM or videoconference (96).
- Applications and productivity: e-mail
applications, document formatting, and remote
access to computers or mobile phones (47).
- Security and safety: data security and
surveillance applications (20).
AN ANALYSIS OF CONTEXT-AWARENESS IN COMMERCIAL MOBILE SERVICES
179
- Entertainment and self content generation:
photos, video, music, and games downloading,
creating, publishing and sharing (155).
- Personal information management: calendars,
reminders, customization, settings (78).
- Social networking (49).
- Mobile experience enhancers: new interfaces,
content adaptation, voice to text conversion, 2D
codes reading (72).
- Miscellanea (32).
Most categories include some subtypes of
services which share the final objective but differ in
their functional implementation. It is the case of
multimedia content and information services. Both
have driven the commercial production of mobile
applications in the last years (accounting for 21%
and 18% over the total).
The other main categories are connectivity and
communications (13%), location and tracking
services (12.7%) and personal information managers
(10.6%).
b) Towards mobile 2.0: downloading, but also
sharing and uploading contents.
“Mobile 2.0” is the way to refer to the convergence
between the social web (or Web 2.0) and the basics
of mobility (personal, localized and always-on).
From a practical point of view, Mobile 2.0 is about
connecting your phone to download your favourite
podcasts, read your RSS feeds, do a one-click image
upload to an on-line photo management and sharing
application, consult the location map while on the
road, tag your streamed videos or update your
moblog.
Figure 1: Evolution of content services (percentage of
services within the total of each quarter).
Using Mobile 2.0 applications needs broadening
the type of user operations, going beyond simple
downloading. This trend is somehow shown in
Figure 1, which describes the evolution of content
services according to our data. To compose Figure 1,
we have divided the services in the “Entertainment
and self generation content” category between
“downloading” and “uploading” applications.
It is noticeable that during 2003-2005, the
content offer was mainly focused on data
downloads, whereas from 2006 on, an increasing
trend in services supporting the creation and sharing
of mobile content is detected. At the same time, the
presence of other categories, almost undeveloped
before, are intensified: it is the case of browsing and
searching or doing social networking.
c) A technological view: enhanced networks and
sensing mobile devices.
There are two key points regarding technology that
shape the changes of the mobile ecosystem during
2003-2008: a) mobile devices have evolved from
traditional mobile phones to smart devices with
increasingly embedded technology and b) the
communication infrastructure is not based on
cellular technology any more. Cellular
communication networks have enhanced their
performance and availability, but alternative
technologies have shown up and increased their
penetration rate.
With respect to mobile devices features, Figure 2
illustrates an approximated timeline on how new
technologies have been embedded into mobile
devices. The arrows point out the early introduction
of a technology in a commercial phone in the
general market, although its technical availability
may be previously detected and its availability as a
commercial common feature may not have happened
until several months later.
Figure 2: Approximate timeline of technologies in mobile
devices.
On the other hand, a very general picture of
communication infrastructures shows that:
- Cellular networks have increased their data rate,
through UMTS/WCDMA technologies
(384kbps) and its enhanced versions: HSDPA
(14.4Mbps), HSUPA (5.6Mbps), HSPA+ (42 /
11.5Mbps) and the next LTE – 3GPP Release 8
(>100 / >50Mbps).
- Growing production of standards: WiFi (IEEE
802.11g, June 2003; next IEEE 802.11n in
2009); WiBRO (TTA, late 2005), WiMAX
(ITU, October 2007), LTE (GSA, January
2008).
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180
- Great take off of WiFi networks, with 89%
growth of WiFi business Hotspots (those
located in airports, hotels, retailers, etc.) over
H2 2007 (iPass, 2008).
- Fixed to Mobile Convergence (FMC) has been a
well-known strategy of some operators,
adopting UMA and IMS in order to provide
better indoors mobile coverage.
- Enhancements in location technologies: E-911
in USA, market-driven deployment of location
based services in Asia-Pacific zone (DTI, 2004),
growing integration of GPS receivers in mobile
devices all around the world.
d) Business: mobile service providers shift from
operators towards software companies.
Generally, the development and commercialization
of a mobile service implies the interaction of a
number of stakeholders. Obviously, the value chain
(or network) composition is very dependent of the
final service. For example, location based services
value chains are generally complex: in the case of an
A-GPS mobile location server, it is possible to
identify at least ten roles doing their part to build the
final service (Bernardos et al., 2007), and it will be
the mobile operator the one offering and billing the
service. On the other hand, a Bluetooth based social
application, offering discovery of peers and
communications will only require an application
provider and, indirectly, a handset compatible
provider. In this case, the user will get the
application directly from the service provider
website, and will be not charged for using it.
Figure 3: Comparison of mobile services’ providers.
On the whole, operators start to change their
walled-garden strategies (Wieland, 2007) towards
more open ones, in part to incentive data traffic
through popular 2.0 applications and to let the users
browse in a more familiar way. Well-known web
services providers that have mobilized their
applications (p.e. Google, Yahoo! or Skype) are
acting as users’ attractors to mobile data services.
From our analysis of data, we get the following
picture (Figure 3): mobile operators started
dominating the provision of content and services to
mobile devices, whereas in the last six quarters this
market has surrendered to Internet software service
providers.
5 CONTEXT-AWARENESS IN
COMMERCIAL MOBILE
SERVICES
5.1 A List of Context-Aware Features
From the classification of mobile services proposed
in Section 4.1, the reader might conclude that many
of the considered services are not context-aware at
all. But some of them –although far from being truly
context-aware applications– could have some
‘context-aware’ features; intuitively, it is the case,
for example, of those services grouped into the
‘location and navigation’ or ‘social networks’
categories.
Measuring the context-awareness level of a
mobile service is not an easy task. For our analysis,
we have identified a number of basic questions that a
context-aware service should be able to answer:
1) Who the target entity/user is and what does
it/he/she want/like? Some services will need to
handle personal descriptors
, these understood as
identity, profile, preferences and group membership
related issues. Personalization and services’
adaptation to the user’s profile are key for many
applications.
2) Where the user is? Location
is a physical
descriptor that usually provides significant
knowledge about the user’s context. Location acts as
a situational filter that is influenced by the
positioning system accuracy. Being the basis of
navigators and trackers, location availability is
making possible some innovative services such as
mobile locative social software, pervasive games or
geotagged content making (photos, blog posts, etc.
may be georeferred).
3) How the user is? Environmental and
biometric data use. Apart from location, context-
aware services may use other physical descriptors to
describe the environment where entities are plunged
(this may be useful, for example, for environmental
and agriculture surveillance applications and
domotics), or even to monitor their biometric
parameters, in order to infer information about the
target entity physical state.
4) What is the current user’s activity? Not
independent of the previous issue, information about
the current activity and logical state
(presence or
connectivity, for example) of a target entity may
AN ANALYSIS OF CONTEXT-AWARENESS IN COMMERCIAL MOBILE SERVICES
181
complete the inferences about its situational
condition. Features such as presence announcement
and state dissemination or availability notifications
are considered in this point.
5) What does the user intend? This feature is
related to personal or professional activity data
gathering, under the shape of calendars, schedules or
notifications, or behavioural patterns.
6) Who/what is near the user? In certain
applications, building a social group based on
proximity issues with defined privacy levels and
collaboration policies is the service’s leitmotif.
Context-aware services combine physical and
situational data with the management of preferences
and interests, creating social networks which
promote direct interaction among peers. Apart from
discovering
people, discovering and interacting with
daily objects through wireless location (WiFi or BT
based systems, for example) and proximity
technologies (such as NFC or RFID) is also possible.
7) With whom the user may communicate?
Applications which are focused on enabling peer
communications make possible the formation of
proximity-based groups.
8) How are the user’s interaction
mechanisms? Context-awareness aims at
facilitating daily living and interaction with the
environment. In the last years, mobile devices have
increased the number of embedded sensors they
have. Accelerometers, cameras, gyroscopes, etc.
enable more intuitive interfaces
: pointing an object
to get information about it or using a 2D sensor
reader to make easier the information search process
also increase the development of mobile context-
awareness.
Table 1: A list of context-aware features.
CONTEXT-AWARE FEATURES
PERSONAL
1 Identity and profile management
2 Preferences and group membership
management
PHYSICAL
3 Positioning capabilities
4
Environmental or biometric data
acquisition and management
ACTIVITY
5 Connectivity and presence information
6 Activity data gathering and storing
RESOURCES MANAGEMENT & COMMUNICATIONS
7 Nearby resources discovery
8 Resources management and allocation
9 Peer to peer communications
INTERFACES
10 Sensor-assisted HCIs
Elaborating on these questions, Table 1 gathers
some features enabling context-awareness. From
their combination, mobile services may be built:
features 1, 2, 3, 5 and 7 may be identified in a
mobile social software application, while a sport
monitoring service may need to handle
characteristics 1, 3, 4 and 6.
In the next Section we analyze the
implementation of these features in the stored data.
5.2 Some Results
- Limited but detectable use of context-aware
features. 20% over the total of analyzed services are
using personal descriptors, only 8% are employing
physical parameters and managing resources and
communications, while 5% of the services are using
activity descriptors. At least one of the considered
features appears in 47% of the 735 services. Around
49% of these services are just implementing one of
the features; in fact, only 9.4% employ more than
four context-aware characteristics.
- Upward trend in personalization and emergence
of sensor-assisted HCIs. Discarding the incomplete
series of 2003 and 2008 and aggregating the rest of
the services in two biannual periods (2004-2005 and
2006-2007), Figure 4 shows a general increase of
context-awareness.
Personalization (identity and profile, preferences
and group membership) appears as a general trend.
Real time information about the user connectivity
(logical state) is also increasingly used. On the other
hand, peer to peer communications have crossed the
barrier of mobility in the second period of time.
Almost 16% of the new mobile applications also
manage location descriptors. Finally, services using
new interfaces have significantly augmented in the
period 2006-2007.
0 5 10 15 20 25 30 35
Identity
Profile, preferences, group
Positioning capabilities
Environmental or biometric data
Logical state info.
Activity data gathering
Nearby resources discovery
Social network
Resources allocation
Peer to peer communications
Sensor-assisted HCIs
% 2004-2005 % 2006-2007
Figure 4: A biannual comparison of context-awareness
implementation in mobile services. Percentage over the
total production in the periods of analysis (300 services in
2004-2005 and 304 services in 2006-2007).
- LBS lead the group of precontext-aware
services, together with information,
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182
communications, personal information managers
and social networks applications. Figure 5
compare the implementation of different context-
aware features based on the categories presented in
Section 4.1. It shows that Location and tracking
services are the most personalized and activity aware
ones. Personal information managers do not lag
behind with respect to these two features, although
in general they do not include location as a
descriptor. On the contrary, information services are
increasingly using positioning as a filter. Mobile
commerce services do not use activity data but are
personalized and sometimes related to the user
location. In general, “entertainment and self content
generation” services are scarcely considering the use
of location.
0 102030405060708090
Location and tracking
Information
m-commerce
Browsing and Searching
Connectivity and communications
Security and safety
Entertainment
Applications and productivity
Personal information management
Social networking
Interface
Miscellanea
Personal Physical Activity Resources
Figure 5: Number of services for each category that
implement personal, activity, physical and resource related
features.
Figure 6: Evolution of context-awareness in the periods
2004-2005 and 2006-2007. Data for some of the
categories identified.
When analyzing what kind of services includes
resources discovery and management capabilities,
the “Connectivity and communications” category is
the one which aggregates the greater number of
applications, followed by the “Location and
tracking” and “Social networking” categories. As it
can be noticed, most of the services handling
resources are limitedly using physical filters such as
position, with the obvious exception of “Location
and tracking” category.
6 CONCLUSIONS
This work explains the results of the analysis of a
large database of mobile services, systematically
updated during the period 2003-2008. Apart from
giving a general view of mobile services evolution,
we have focused on studing to which extent context-
awareness is implemented in commercial mobile
services. With this purpose, we have identified
several context-aware descriptors (personal, physical
or activity related) and features (capability of
managing resources, establishing P2P
communications or implementing advanced HCIs),
and evaluated their implementation in mobile
services.
- In general, few commercial mobile services can
be considered fully ‘context-aware’, although
isolated features have been detected in about
half of them.
- Personalization -this understood as the
capability of handling identity, preferences and
group membership information- is the context-
aware feature that most applications implement.
Physical and activity descriptors’ use lags
behind.
- Mobile services are increasingly incorporating
the use of context-awareness, although there is
not a breaking point in the period 2004-2007.
Again, personalization is the most significant
trend.
- Context-aware features have been detected in
services of all the functional categories.
Anyway, services in the following categories
“Location and Navigation”, “Social networks”,
“Information” and “Personal information
management” are showing the highest levels of
context-descriptors’ use.
- Mobile ‘social networking’ applications may be
considered as highly context-aware. They have
remarkably appeared during 2006-2007 and are
intensively using personal descriptors while
discovering and managing resources. Location-
based filtering is also included in some mobile
social services.
- The integration of sensors such as gyroscopes or
accelerometers is making possible new
interaction mechanisms with the environment.
Sensors assisted HCIs proposals have
noticeably grown in 2006-2007.
AN ANALYSIS OF CONTEXT-AWARENESS IN COMMERCIAL MOBILE SERVICES
183
Nowadays favourable boundary conditions -
progressively more connected environments,
evolved mobile devices (with new communication
capabilities, more usable HCIs and embedded
sensors), “literate” users and more established data
markets – seem enough to make context-aware
services enter in the commercial offer. This
“context-awarezation” of mobile services has
already started, even if there is still a long way to go.
ACKNOWLEDGEMENTS
This work has been financed by the Spanish
Ministry of Education and Science under grant
TSI2005-07344 (COLOCAME) and by the
Government of Madrid under grant S-0505/TIC-
0255 (MADRINET).
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