25-08-2017, 09:32 PM
Multimedia Streaming Technology n 4G Mobile Communication Systems full report
[attachment=26868][/u]
Abstract
The popularity and evolution of mobile devices like
laptops, mobile phones and Personal Digital Assistants (PDA),
and the evolution of fast mobile networks in the last decade, have
made it possible to increase the complexity of mobile applications
and services provided to end-users. It is also a spectacular growth
in multimedia communication especially via the World Wide
Web. This paper explore some of the current technology of
mobile devices, mobile networks and multimedia systems, and is
based on the exploration outline some issues for design and
development of mobile multimedia systems in 4G Mobile
Communication System. Fourth-generation mobile
communication systems will combine standardized streaming
with a range of unique services to provide high-quality content
(Multimedia) that meets the specific needs of the rapidly growing
mobile market. By offering higher data-transmission rates up to
20 Mbps more than 3G for wide-area coverage and local-area
coverage, 4G systems will be able to provide high quality
streamed content to the rapidly growing mobile market.
(Abstract)
Keywords-4G Mobile System (CDMA, GSM); Internet
Streaming Media Alliance (ISMA); The Wireless Multimedia
Forum (WMF) (key words)
I. INTRODUCTION
Many portal sites offer streaming audio and video
services for accessing news and entertainment content on the
Internet from a PC. The term multimedia streaming means that
there are more than one media type involved in the
communication, e.g. text and graphics, voice, animations,
video and audio.
We define multimedia to denote the property of
handling a variety of representation media in an integrated
manner. This means that the various sources of media types
are integrated into a single system framework. Currently, three
incompatible proprietary solutions offered by Real Networks,
Microsoft, and Apple dominate the Internet streaming
software market. In the near future, third-generation mobile
communication systems will extend the scope of today’s
Internet streaming solutions by introducing standardized
streaming services, targeting the mobile users specific needs.
By offering higher data-transmission rates up to 20 Mbps
more than 3G for wide-area coverage and local-area coverage,
4G systems will be able to provide high quality streamed
content to the rapidly growing mobile market. In addition to
higher data rates, these systems also will offer value-added
applications supported by an underlying network that
combines streaming services with a range of unique mobile
specific services such as Multimedia content, geographical
positioning, user profiling, and mobile payment. Mobile
cinema ticketing is one example of such a service.
First, the mobile network or a terminal integrated
positioning system such as GPS would determine the users
geographical location. Then, the service would access a
cinema database to generate a list of nearby movie theatres
and a user profile database to determine what kind of movies
the user likes best. Based on the geographical location
information and user-defined preferences, the service would
offer the user a selection of available movies and show times.
The user would then have the option of using the mobile
device to view corresponding movie trailers through a
streaming service.
Upon choosing a film, the user could purchase a
ticket through payment software on the mobile device. This
and other mobile application scenarios present numerous
challenges, such as how to provide spectrum efficient
streaming services over varied radio-access networks to
different types of end-user terminals. Our standard-based
Interactive Media platform addresses these challenges by
using an architecture that fits seamlessly into 4G mobile
communication systems. An integral part of this architecture is
a streaming proxy, which acts on both the service and
transport levels. It is flexible enough to deal with different
operator requirements and that it can provide high-quality
streaming services in a mobile application environment.
II. 4G MOBILE COMMUNICATION SYSTEMS
International Mobile Telecommunications - 2000
(IMT-2000) and the Universal Mobile telecommunications
System (UMTS) will be among the first 3G mobile
communication systems to offer wireless wideband
multimedia services using the Internet protocol. Two
important technological changes will facilitate this
advancement. The first change is a shift from last-generation
radio-access technologies such as the global system for mobile
(GSM) communication, CDMA One (an IS-95 code division
multiple access standard), and personal digital cellular (PDC)
toward more sophisticated systems with higher data-transfer
rates such as the enhanced data.
Fourth-generation mobile communication systems
ISSN : 0975-3397 695
Govind Singh Tanwar et. al. / (IJCSE) International Journal on Computer Science and Engineering
Vol. 02, No. 03, 2010, 695-699
will combine standardized streaming with a range of unique
services to provide high-quality content that meets the specific
needs of the rapidly growing mobile market. GSM
environment (EDGE), wideband CDMA (WCDMA) and
cdma2000[1]. As Figure 1 illustrates, the second important
technology shift is from a vertically integrated to a
horizontally layered service environment. A horizontally
layered 4G service network seamlessly integrates Internet
protocol transport into a mobile service environment with a
variety of access networks, opening up many new
opportunities for IP-based mobile applications.
For example, mobile terminals will be able to access
existing Internet content through protocols and markup
languages such as WAP and WML that are optimized for
wireless application scenarios. 4G mobile communications
will have transmission rates up to 20 Mbps_ higher than of
3G. The technology is expected to be available by the year
2010. 4G is being developed with the following objectives:
1. Speeds up to 50 times higher than of 3G. However,
the actual available bandwidth of 4G is expected to
be about 10 Mbps.
2. Three-dimensional virtual realities imagine personal
video avatars and realistic holograms, and the ability
to feel as if you are present at an event even if you are
not. People, places, and products will be able to
interact as the cyber and real worlds merge.
3. Increased interaction between corroborating
technologies; the smart card in your phone will
automatically pay for or will tell your car to warm up
in the morning as your phone has noted you leaving
the house. We can use new technology such as
CDMA wireless access technology, advanced
antenna systems, next-generation mobile Internet,
quality of service, power amplifier technology, and
wireless access networks in 4G mobile
communication system.4G applications include
high-performance streaming of multimedia content
based on agent technology and saleable media coding
methods. 4G will solve problems like limited
bandwidth in 3G when people are moving and
uncertainty about the availability of bandwidth for
streaming to all users at all times. The 4G networks
will also provide access to support services such as
authentication, security, and billing mechanisms as
well as mobile-specific services such as mobility
management and location-based computing.
Figure 1-The Shift From A Vertically Integrated To A Horizontally Layered
Mobile Service Environment. 4g Network Seamlessly Integrate Internet
Protocol Transport With A Variety Of Access Networks
III. MOBILE STREAMING CHALLENGES
The widespread implementation of mobile streaming
services faces two major challenges: access network and
terminal heterogeneity and content protection.
A. Heterogeneity
In the future, we will have access to a variety of
mobile terminals with a wide range of display sizes and
capabilities. In addition, different radio-access networks will
make multiple maximum-access link speeds available.
Because of the physical characteristics of cellular radio
networks, the quality and, thus, the data rate of an ongoing
connection will also vary, contributing to the heterogeneity
problem. One way to address heterogeneity is to use
appropriately designed capability exchange mechanisms that
enable the terminal and media server to negotiate mobile
terminal and mobile network capabilities and user preferences.
This approach lets the server send multimedia data adapted to
the user’s mobile terminal and the network. For example, a
user accessing a specific service via a WCDMA network
could get the content delivered at a higher bit rate than
someone using a general packet radio service or GSM
network[2]. Similarly, when a person using a mobile
multimedia terminal with a built-in low quality speaker plugs
in a high-fidelity headphone, a dynamic capability exchange
takes place, upgrading the transmission to a high-quality audio
stream for the remainder of the session. A related problem is
how to efficiently deliver streamed multimedia content over
various radio-access networks with different transmission
conditions. This is achievable only if the media transport
protocols incorporate the specific characteristics of wireless
links, such as delays due to retransmissions of corrupted data
packets. Here, proxies are a suitable approach for caching data
packets and optimizing the data transport over the wireless
links to a mobile terminal.
ISSN : 0975-3397 696
Govind Singh Tanwar et. al. / (IJCSE) International Journal on Computer Science and Engineering
Vol. 02, No. 03, 2010, 695-699
Figure 2 The protocols integrate simultaneously playing video, audio, images,
and formatted text into mobile multimedia applications.
B. Content Protection
At the application level, controlling what users can do
with content is an important challenge. The simplest form of
content protection is simply disallowing the storage of
received content. Content protection is part of the much
broader digital rights management (DRM) concept, which uses
techniques such as encryption and conditional access based on
usage rules to protect and manage access to multimedia data.
Content providers are reluctant to deliver premium content
over digital networks without DRM mechanisms in place to
prevent widespread illegal copying of valuable multimedia
content such as music and movies.
IV. STREAMING STANDARDIZATION
Several organization and industry groups including
the Internet Streaming Media Alliance (ISMA) and the
Wireless Multimedia Forum (WMF) have recognized the need
for standardization of streaming services. Mobile streaming
services in particular require a common standardized format
because it is unlikely that mobile terminals will be able to
support all proprietary Internet streaming formats in the near
future. Using standardized components such as multimedia
protocol stacks and codecs video and audio
compression/decompression software in end-user equipment
will help reduce terminal costs. Furthermore, preparing and
providing content in one standardized format is less time
consuming and expensive than setting up content for several
proprietary streaming solutions individually. We must to
address mobile streaming standardization. Streaming services
as an important building block of 4G multimedia applications.
In addition to mobile streaming standardization, it is also
require to addresses other applications such as
videoconferencing and services for composing and receiving
multimedia messages. Multimedia messaging services can
include text, images, and audio, short video clips, or videostream
URLs. We have to use the mobile packet-switched
streaming service. This service integrates simultaneously
playing video, audio, images, and formatted text into mobile
multimedia applications. The protocols and terminals for
streaming applications are less complex than for
conversational services, which require media input devices
and encoders. There are some standard specifies both
protocols and codecs. The protocols and their applications,
illustrated in Figure 3, are " Real-time streaming protocol
(RTSP) and session description protocol (SDP) for session
setup and control, " Synchronized Multimedia Integration
Language(SMIL) for session layout description, " Hypertext
transfer protocol (HTTP) and transmission control protocol
(TCP) for transporting static media such as session layouts,
images, and text, and " Real-time transfer protocol (RTP) for
transporting real-time media such as video, speech, and audio.
The codec’s and media types are " H.263 video, " MPEG-4
simple visual profile video (optional), " AMR (adaptive
multirate) speech, " MPEG-4 AAC low complexity (AAC-LC)
audio (recommended but optional), " JPEG and GIF images,
and " XHTML-encoded, formatted text. To enable
interoperability between content servers, especially when inter
working with MMS[3], the standard specifies using MPEG-4
as an optional file format for storing media on the server. The
standardization process selected individual codec’s on the
basis of both compression efficiency and complexity. When
combined using the SMIL presentation description language,
the codec’s enable rich multimedia presentations and
applications, including video, audio, slideshows, and
Multilanguage subtitling. Figure 3 shows the logical
components and data flow in a block diagram of a Streaming
Standardization mobile-streaming terminal, including the
individual codec’s and presentation control. The network
transmits the data and passes it to the application from
Standard format link Layer. The application demultiplexes the
data and distributes it to the corresponding video and audio
decoders. The streaming standard offers the possibility of
creating presentations in which several media elements such as
video, audio, images, and formatted text play at the same time.
SMIL, an XML-based presentation language developed by
the World Wide Web Consortium, is the _glue_ that
combines these different elements to create an interactive
multimedia presentation. SMIL is HTML with additional
notions of time and temporal behavior. Thus, it can describe a
media screen and control the placement of media elements in
space and time. The streaming client interprets the SMIL
scene description and uses it to control the spatial layout and
synchronization in the multimedia presentation. The standard
specifically uses the SMIL 2.0 Basic Language Profile as well
as the Event Timing, Meta Information, and Media Clipping
modules.
The additional modules add functionality such as
changes in the presentation schedule based on user interaction
(Event Timing), sending eta information about the multimedia
data (Misinformation), and rendering only parts of a
transmitted media stream (Media- Clipping). In addition, a
streaming client can support the Prefetch Control module,
which lets the content creator include hints about when to start
a media stream.
ISSN : 0975-3397 697
Govind Singh Tanwar et. al. / (IJCSE) International Journal on Computer Science and Engineering
Vol. 02, No. 03, 2010, 695-699
Figure 3 Overview of streaming client
V. INTERACTIVE MEDIA PLAT-FORM
The Interactive Media system, illustrated in Figure 4,
is a software platform for mobile streaming applications.
Designed as an end-to-end solution, the system consists of
_Dedicated content creation machines, _A player application
that runs on widely used operating systems such as Windows
CE and EPOC, _Content servers that hold the newly
created multimedia content, and A proxy, which builds the
interface between the player application and other parts of the
platform.
The client uses HTTP to request a SMIL presentation
from a Web server. Within the SMIL presentation, the client
finds links to the streaming content, which it acquires from the
streaming servers. Static content, such as an image, is fetched
from a Web server via HTTP. The chosen protocols are fully
compliant with existing standards. HTTP provides access to
static content through a TCP connection, while RTP packets
transport streaming content via UDP connections. RTSP
manages streaming sessions. As the Streaming standardization
standard requires, the system uses SDP via an RTSP
connection to access stream descriptions. Introducing a proxy
is necessary to fulfill the requirements of a mobile Internet
application using off-the-shelf components designed for the
fixed Internet[3].
It also shields the core network from the back-end
components and vice versa. Additionally, the back-end
components can be located outside the operator domain, using
the proxy with a firewall extension. This leads to a truly
distributed architecture that puts the components into locations
where they operate most effectively.
Figure 4 Interactive Media platform.
A. Content Creation Machines
The content creation machines depicted in Figure 4
host the applications needed for creating both live and offline
content. They are used to prepare streaming content, for
example, to edit videos and images and encode them in the
appropriate formats for mobile streaming. Additionally, these
machines create the SMIL files, which are a kind of storybook
for the interactive presentation. They upload the content to the
streaming servers for dynamic content and to the Web servers,
which hold the static content and the SMIL files.
B. Player Application
The player application renders multimedia content
and lets users navigate through the SMIL presentations. Each
multimedia element can be hyperlinked to other presentations.
The players SMIL implementation is fully standard-compliant
as are the supported codec’s, which decode multimedia data
and render it on the output devices. Plug-in capabilities
simplify extending the player with additional codecs.
Applying skins changes the player applications appearance. A
skin is a structure that adapts the look of an applications user
interface. An application can have several skins. For example,
a branding application implements the skin as images mapped
on the side of the players display and control elements.
Selecting a different set of images for the skin brands the
application for various customers. After launching the player
application separately, the user can select a SMIL presentation
or a single stream to navigate through a hierarchy of SMIL
presentations. An alternative is to click a hyperlink in a
standard Web browser that anchors a SMIL presentation. In
either case, the player fetches the SMIL file from a Web server
via the proxy. The players SMIL engine interprets the contents
of the SMIL file and fetches the streams (using the RTSP
protocol) and the static content (using HTTP) according to the
storyboard the SMIL file describes[3]. The engine launches
the content-specific codec’s to render the information. Each of
the elements in the SMIL file can have an underlying
ISSN : 0975-3397 698
Govind Singh Tanwar et. al. / (IJCSE) International Journal on Computer Science and Engineering
Vol. 02, No. 03, 2010, 695-699
hyperlink. When the user clicks on a region of the screen that
is associated with a hyperlink, the SMIL engine fetches the
anchored file and interprets its content.
B. Content Servers
Two kinds of back-end servers store the content the
player renders: Off-the-shelf Web servers hold the SMIL
pages, images, and other static content, and dedicated
streaming servers store streaming content and related
information. On reception of an HTTP GET request for an
SMIL file from the proxy or the player, the Web server
processes the request and fetches the appropriate content.
Subsequent HTTP GET requests fetch the associated static
content, or the user can click on a hyperlink in a SMIL file to
fetch the new presentation. The player application uses the
RTSP protocol to control the operation of the streaming
server. After fetching the description of a streaming session,
which it transports using the session description protocol, the
player application sets up the streams of this session, for
example, the video and audio track. When it receives an RTSP
PLAY request, the server starts sending out RTP packets that
transport the streaming content. Each stream can be in a
different state for example, being set up, playing, paused.
Therefore, the streaming servers must keep track of all active
sessions. The server uses the real-time control protocol to
provide the player, proxy, and streaming server with additional
information about the session such as packet loss. Each stream
that the server sends out has an RTCP connection.
C. Proxy
The proxy is the systems interface to both the radio
network and the back-end components. This central
components major task is to adapt the streaming multimedia
on the fly to the mobile network links continuously changing
conditions. When a client requests an interactive multimedia
presentation, the streaming proxy initially loads the SMIL file.
The proxy’s basic HTTP functionality optimizes the client
connection according to the mobile IP networks
characteristics. The client fetches the SMIL file and interprets
it on the client, then the client requests both static and
streaming content from the back-end servers. Acquiring static
content such as images and text files is very straightforward,
but the proxy’s value becomes more apparent when it
transmits streaming data to the client[4]. During transmission
of streaming data, the proxy dynamically adapts the delivered
quality of service in accordance with available bandwidth. To
achieve this dynamic adaptation, the proxy uses feedback
information from the player application, radio network, and IP
network. The user, content-provider, and operator use the
proxy to configure preferences. A content provider can specify
a minimum bandwidth to ensure acceptable video-stream
quality. If this bandwidth is not available, a slide show is
presented instead. If the current bandwidth is insufficient for
delivering a video, the proxy switches on the fly to a lower
bandwidth as long as the QoS does not drop below a
predefined value. The operator also has the option of limiting
bandwidth consumption to a certain user group, such as flatrate
subscribers. The system creates a reliable connection
between the proxy and the client by retransmitting lost UDP
packets for example, if the user passes through a tunnel and
temporarily loses connection to the radio network. To provide
streaming without losing information, the proxy automatically
pauses the presentation when the connection is lost and then
uncaused it after the terminal regains the network link. The
proxy is also the interface to the operator’s network
components, including operation and maintenance, charging
and billing, and subscription management. Mobile network
operators can easily integrate the Interactive Media platform
into existing structures and combine it with off-the-shelf
products. The proxy itself is fully scalable at the machine
level, using Telco standard load-balancing solutions when
multiple machines use the same IP address[4]. The proxy’s
major task is to adapt the streaming multimedia to the mobile
network link’s continuously changing conditions.
[attachment=26868][/u]
Abstract
The popularity and evolution of mobile devices like
laptops, mobile phones and Personal Digital Assistants (PDA),
and the evolution of fast mobile networks in the last decade, have
made it possible to increase the complexity of mobile applications
and services provided to end-users. It is also a spectacular growth
in multimedia communication especially via the World Wide
Web. This paper explore some of the current technology of
mobile devices, mobile networks and multimedia systems, and is
based on the exploration outline some issues for design and
development of mobile multimedia systems in 4G Mobile
Communication System. Fourth-generation mobile
communication systems will combine standardized streaming
with a range of unique services to provide high-quality content
(Multimedia) that meets the specific needs of the rapidly growing
mobile market. By offering higher data-transmission rates up to
20 Mbps more than 3G for wide-area coverage and local-area
coverage, 4G systems will be able to provide high quality
streamed content to the rapidly growing mobile market.
(Abstract)
Keywords-4G Mobile System (CDMA, GSM); Internet
Streaming Media Alliance (ISMA); The Wireless Multimedia
Forum (WMF) (key words)
I. INTRODUCTION
Many portal sites offer streaming audio and video
services for accessing news and entertainment content on the
Internet from a PC. The term multimedia streaming means that
there are more than one media type involved in the
communication, e.g. text and graphics, voice, animations,
video and audio.
We define multimedia to denote the property of
handling a variety of representation media in an integrated
manner. This means that the various sources of media types
are integrated into a single system framework. Currently, three
incompatible proprietary solutions offered by Real Networks,
Microsoft, and Apple dominate the Internet streaming
software market. In the near future, third-generation mobile
communication systems will extend the scope of today’s
Internet streaming solutions by introducing standardized
streaming services, targeting the mobile users specific needs.
By offering higher data-transmission rates up to 20 Mbps
more than 3G for wide-area coverage and local-area coverage,
4G systems will be able to provide high quality streamed
content to the rapidly growing mobile market. In addition to
higher data rates, these systems also will offer value-added
applications supported by an underlying network that
combines streaming services with a range of unique mobile
specific services such as Multimedia content, geographical
positioning, user profiling, and mobile payment. Mobile
cinema ticketing is one example of such a service.
First, the mobile network or a terminal integrated
positioning system such as GPS would determine the users
geographical location. Then, the service would access a
cinema database to generate a list of nearby movie theatres
and a user profile database to determine what kind of movies
the user likes best. Based on the geographical location
information and user-defined preferences, the service would
offer the user a selection of available movies and show times.
The user would then have the option of using the mobile
device to view corresponding movie trailers through a
streaming service.
Upon choosing a film, the user could purchase a
ticket through payment software on the mobile device. This
and other mobile application scenarios present numerous
challenges, such as how to provide spectrum efficient
streaming services over varied radio-access networks to
different types of end-user terminals. Our standard-based
Interactive Media platform addresses these challenges by
using an architecture that fits seamlessly into 4G mobile
communication systems. An integral part of this architecture is
a streaming proxy, which acts on both the service and
transport levels. It is flexible enough to deal with different
operator requirements and that it can provide high-quality
streaming services in a mobile application environment.
II. 4G MOBILE COMMUNICATION SYSTEMS
International Mobile Telecommunications - 2000
(IMT-2000) and the Universal Mobile telecommunications
System (UMTS) will be among the first 3G mobile
communication systems to offer wireless wideband
multimedia services using the Internet protocol. Two
important technological changes will facilitate this
advancement. The first change is a shift from last-generation
radio-access technologies such as the global system for mobile
(GSM) communication, CDMA One (an IS-95 code division
multiple access standard), and personal digital cellular (PDC)
toward more sophisticated systems with higher data-transfer
rates such as the enhanced data.
Fourth-generation mobile communication systems
ISSN : 0975-3397 695
Govind Singh Tanwar et. al. / (IJCSE) International Journal on Computer Science and Engineering
Vol. 02, No. 03, 2010, 695-699
will combine standardized streaming with a range of unique
services to provide high-quality content that meets the specific
needs of the rapidly growing mobile market. GSM
environment (EDGE), wideband CDMA (WCDMA) and
cdma2000[1]. As Figure 1 illustrates, the second important
technology shift is from a vertically integrated to a
horizontally layered service environment. A horizontally
layered 4G service network seamlessly integrates Internet
protocol transport into a mobile service environment with a
variety of access networks, opening up many new
opportunities for IP-based mobile applications.
For example, mobile terminals will be able to access
existing Internet content through protocols and markup
languages such as WAP and WML that are optimized for
wireless application scenarios. 4G mobile communications
will have transmission rates up to 20 Mbps_ higher than of
3G. The technology is expected to be available by the year
2010. 4G is being developed with the following objectives:
1. Speeds up to 50 times higher than of 3G. However,
the actual available bandwidth of 4G is expected to
be about 10 Mbps.
2. Three-dimensional virtual realities imagine personal
video avatars and realistic holograms, and the ability
to feel as if you are present at an event even if you are
not. People, places, and products will be able to
interact as the cyber and real worlds merge.
3. Increased interaction between corroborating
technologies; the smart card in your phone will
automatically pay for or will tell your car to warm up
in the morning as your phone has noted you leaving
the house. We can use new technology such as
CDMA wireless access technology, advanced
antenna systems, next-generation mobile Internet,
quality of service, power amplifier technology, and
wireless access networks in 4G mobile
communication system.4G applications include
high-performance streaming of multimedia content
based on agent technology and saleable media coding
methods. 4G will solve problems like limited
bandwidth in 3G when people are moving and
uncertainty about the availability of bandwidth for
streaming to all users at all times. The 4G networks
will also provide access to support services such as
authentication, security, and billing mechanisms as
well as mobile-specific services such as mobility
management and location-based computing.
Figure 1-The Shift From A Vertically Integrated To A Horizontally Layered
Mobile Service Environment. 4g Network Seamlessly Integrate Internet
Protocol Transport With A Variety Of Access Networks
III. MOBILE STREAMING CHALLENGES
The widespread implementation of mobile streaming
services faces two major challenges: access network and
terminal heterogeneity and content protection.
A. Heterogeneity
In the future, we will have access to a variety of
mobile terminals with a wide range of display sizes and
capabilities. In addition, different radio-access networks will
make multiple maximum-access link speeds available.
Because of the physical characteristics of cellular radio
networks, the quality and, thus, the data rate of an ongoing
connection will also vary, contributing to the heterogeneity
problem. One way to address heterogeneity is to use
appropriately designed capability exchange mechanisms that
enable the terminal and media server to negotiate mobile
terminal and mobile network capabilities and user preferences.
This approach lets the server send multimedia data adapted to
the user’s mobile terminal and the network. For example, a
user accessing a specific service via a WCDMA network
could get the content delivered at a higher bit rate than
someone using a general packet radio service or GSM
network[2]. Similarly, when a person using a mobile
multimedia terminal with a built-in low quality speaker plugs
in a high-fidelity headphone, a dynamic capability exchange
takes place, upgrading the transmission to a high-quality audio
stream for the remainder of the session. A related problem is
how to efficiently deliver streamed multimedia content over
various radio-access networks with different transmission
conditions. This is achievable only if the media transport
protocols incorporate the specific characteristics of wireless
links, such as delays due to retransmissions of corrupted data
packets. Here, proxies are a suitable approach for caching data
packets and optimizing the data transport over the wireless
links to a mobile terminal.
ISSN : 0975-3397 696
Govind Singh Tanwar et. al. / (IJCSE) International Journal on Computer Science and Engineering
Vol. 02, No. 03, 2010, 695-699
Figure 2 The protocols integrate simultaneously playing video, audio, images,
and formatted text into mobile multimedia applications.
B. Content Protection
At the application level, controlling what users can do
with content is an important challenge. The simplest form of
content protection is simply disallowing the storage of
received content. Content protection is part of the much
broader digital rights management (DRM) concept, which uses
techniques such as encryption and conditional access based on
usage rules to protect and manage access to multimedia data.
Content providers are reluctant to deliver premium content
over digital networks without DRM mechanisms in place to
prevent widespread illegal copying of valuable multimedia
content such as music and movies.
IV. STREAMING STANDARDIZATION
Several organization and industry groups including
the Internet Streaming Media Alliance (ISMA) and the
Wireless Multimedia Forum (WMF) have recognized the need
for standardization of streaming services. Mobile streaming
services in particular require a common standardized format
because it is unlikely that mobile terminals will be able to
support all proprietary Internet streaming formats in the near
future. Using standardized components such as multimedia
protocol stacks and codecs video and audio
compression/decompression software in end-user equipment
will help reduce terminal costs. Furthermore, preparing and
providing content in one standardized format is less time
consuming and expensive than setting up content for several
proprietary streaming solutions individually. We must to
address mobile streaming standardization. Streaming services
as an important building block of 4G multimedia applications.
In addition to mobile streaming standardization, it is also
require to addresses other applications such as
videoconferencing and services for composing and receiving
multimedia messages. Multimedia messaging services can
include text, images, and audio, short video clips, or videostream
URLs. We have to use the mobile packet-switched
streaming service. This service integrates simultaneously
playing video, audio, images, and formatted text into mobile
multimedia applications. The protocols and terminals for
streaming applications are less complex than for
conversational services, which require media input devices
and encoders. There are some standard specifies both
protocols and codecs. The protocols and their applications,
illustrated in Figure 3, are " Real-time streaming protocol
(RTSP) and session description protocol (SDP) for session
setup and control, " Synchronized Multimedia Integration
Language(SMIL) for session layout description, " Hypertext
transfer protocol (HTTP) and transmission control protocol
(TCP) for transporting static media such as session layouts,
images, and text, and " Real-time transfer protocol (RTP) for
transporting real-time media such as video, speech, and audio.
The codec’s and media types are " H.263 video, " MPEG-4
simple visual profile video (optional), " AMR (adaptive
multirate) speech, " MPEG-4 AAC low complexity (AAC-LC)
audio (recommended but optional), " JPEG and GIF images,
and " XHTML-encoded, formatted text. To enable
interoperability between content servers, especially when inter
working with MMS[3], the standard specifies using MPEG-4
as an optional file format for storing media on the server. The
standardization process selected individual codec’s on the
basis of both compression efficiency and complexity. When
combined using the SMIL presentation description language,
the codec’s enable rich multimedia presentations and
applications, including video, audio, slideshows, and
Multilanguage subtitling. Figure 3 shows the logical
components and data flow in a block diagram of a Streaming
Standardization mobile-streaming terminal, including the
individual codec’s and presentation control. The network
transmits the data and passes it to the application from
Standard format link Layer. The application demultiplexes the
data and distributes it to the corresponding video and audio
decoders. The streaming standard offers the possibility of
creating presentations in which several media elements such as
video, audio, images, and formatted text play at the same time.
SMIL, an XML-based presentation language developed by
the World Wide Web Consortium, is the _glue_ that
combines these different elements to create an interactive
multimedia presentation. SMIL is HTML with additional
notions of time and temporal behavior. Thus, it can describe a
media screen and control the placement of media elements in
space and time. The streaming client interprets the SMIL
scene description and uses it to control the spatial layout and
synchronization in the multimedia presentation. The standard
specifically uses the SMIL 2.0 Basic Language Profile as well
as the Event Timing, Meta Information, and Media Clipping
modules.
The additional modules add functionality such as
changes in the presentation schedule based on user interaction
(Event Timing), sending eta information about the multimedia
data (Misinformation), and rendering only parts of a
transmitted media stream (Media- Clipping). In addition, a
streaming client can support the Prefetch Control module,
which lets the content creator include hints about when to start
a media stream.
ISSN : 0975-3397 697
Govind Singh Tanwar et. al. / (IJCSE) International Journal on Computer Science and Engineering
Vol. 02, No. 03, 2010, 695-699
Figure 3 Overview of streaming client
V. INTERACTIVE MEDIA PLAT-FORM
The Interactive Media system, illustrated in Figure 4,
is a software platform for mobile streaming applications.
Designed as an end-to-end solution, the system consists of
_Dedicated content creation machines, _A player application
that runs on widely used operating systems such as Windows
CE and EPOC, _Content servers that hold the newly
created multimedia content, and A proxy, which builds the
interface between the player application and other parts of the
platform.
The client uses HTTP to request a SMIL presentation
from a Web server. Within the SMIL presentation, the client
finds links to the streaming content, which it acquires from the
streaming servers. Static content, such as an image, is fetched
from a Web server via HTTP. The chosen protocols are fully
compliant with existing standards. HTTP provides access to
static content through a TCP connection, while RTP packets
transport streaming content via UDP connections. RTSP
manages streaming sessions. As the Streaming standardization
standard requires, the system uses SDP via an RTSP
connection to access stream descriptions. Introducing a proxy
is necessary to fulfill the requirements of a mobile Internet
application using off-the-shelf components designed for the
fixed Internet[3].
It also shields the core network from the back-end
components and vice versa. Additionally, the back-end
components can be located outside the operator domain, using
the proxy with a firewall extension. This leads to a truly
distributed architecture that puts the components into locations
where they operate most effectively.
Figure 4 Interactive Media platform.
A. Content Creation Machines
The content creation machines depicted in Figure 4
host the applications needed for creating both live and offline
content. They are used to prepare streaming content, for
example, to edit videos and images and encode them in the
appropriate formats for mobile streaming. Additionally, these
machines create the SMIL files, which are a kind of storybook
for the interactive presentation. They upload the content to the
streaming servers for dynamic content and to the Web servers,
which hold the static content and the SMIL files.
B. Player Application
The player application renders multimedia content
and lets users navigate through the SMIL presentations. Each
multimedia element can be hyperlinked to other presentations.
The players SMIL implementation is fully standard-compliant
as are the supported codec’s, which decode multimedia data
and render it on the output devices. Plug-in capabilities
simplify extending the player with additional codecs.
Applying skins changes the player applications appearance. A
skin is a structure that adapts the look of an applications user
interface. An application can have several skins. For example,
a branding application implements the skin as images mapped
on the side of the players display and control elements.
Selecting a different set of images for the skin brands the
application for various customers. After launching the player
application separately, the user can select a SMIL presentation
or a single stream to navigate through a hierarchy of SMIL
presentations. An alternative is to click a hyperlink in a
standard Web browser that anchors a SMIL presentation. In
either case, the player fetches the SMIL file from a Web server
via the proxy. The players SMIL engine interprets the contents
of the SMIL file and fetches the streams (using the RTSP
protocol) and the static content (using HTTP) according to the
storyboard the SMIL file describes[3]. The engine launches
the content-specific codec’s to render the information. Each of
the elements in the SMIL file can have an underlying
ISSN : 0975-3397 698
Govind Singh Tanwar et. al. / (IJCSE) International Journal on Computer Science and Engineering
Vol. 02, No. 03, 2010, 695-699
hyperlink. When the user clicks on a region of the screen that
is associated with a hyperlink, the SMIL engine fetches the
anchored file and interprets its content.
B. Content Servers
Two kinds of back-end servers store the content the
player renders: Off-the-shelf Web servers hold the SMIL
pages, images, and other static content, and dedicated
streaming servers store streaming content and related
information. On reception of an HTTP GET request for an
SMIL file from the proxy or the player, the Web server
processes the request and fetches the appropriate content.
Subsequent HTTP GET requests fetch the associated static
content, or the user can click on a hyperlink in a SMIL file to
fetch the new presentation. The player application uses the
RTSP protocol to control the operation of the streaming
server. After fetching the description of a streaming session,
which it transports using the session description protocol, the
player application sets up the streams of this session, for
example, the video and audio track. When it receives an RTSP
PLAY request, the server starts sending out RTP packets that
transport the streaming content. Each stream can be in a
different state for example, being set up, playing, paused.
Therefore, the streaming servers must keep track of all active
sessions. The server uses the real-time control protocol to
provide the player, proxy, and streaming server with additional
information about the session such as packet loss. Each stream
that the server sends out has an RTCP connection.
C. Proxy
The proxy is the systems interface to both the radio
network and the back-end components. This central
components major task is to adapt the streaming multimedia
on the fly to the mobile network links continuously changing
conditions. When a client requests an interactive multimedia
presentation, the streaming proxy initially loads the SMIL file.
The proxy’s basic HTTP functionality optimizes the client
connection according to the mobile IP networks
characteristics. The client fetches the SMIL file and interprets
it on the client, then the client requests both static and
streaming content from the back-end servers. Acquiring static
content such as images and text files is very straightforward,
but the proxy’s value becomes more apparent when it
transmits streaming data to the client[4]. During transmission
of streaming data, the proxy dynamically adapts the delivered
quality of service in accordance with available bandwidth. To
achieve this dynamic adaptation, the proxy uses feedback
information from the player application, radio network, and IP
network. The user, content-provider, and operator use the
proxy to configure preferences. A content provider can specify
a minimum bandwidth to ensure acceptable video-stream
quality. If this bandwidth is not available, a slide show is
presented instead. If the current bandwidth is insufficient for
delivering a video, the proxy switches on the fly to a lower
bandwidth as long as the QoS does not drop below a
predefined value. The operator also has the option of limiting
bandwidth consumption to a certain user group, such as flatrate
subscribers. The system creates a reliable connection
between the proxy and the client by retransmitting lost UDP
packets for example, if the user passes through a tunnel and
temporarily loses connection to the radio network. To provide
streaming without losing information, the proxy automatically
pauses the presentation when the connection is lost and then
uncaused it after the terminal regains the network link. The
proxy is also the interface to the operator’s network
components, including operation and maintenance, charging
and billing, and subscription management. Mobile network
operators can easily integrate the Interactive Media platform
into existing structures and combine it with off-the-shelf
products. The proxy itself is fully scalable at the machine
level, using Telco standard load-balancing solutions when
multiple machines use the same IP address[4]. The proxy’s
major task is to adapt the streaming multimedia to the mobile
network link’s continuously changing conditions.