TuC2-4
The 1st International Conference on Next Generation Network (NGNCON 2006) Hyatt Regency Jeju, Korea / July 9 - 13, 2006
Practical Implementation of Interactive Data Broadcasting Services in IPTV over the NGN Lark Kwon Choi*, Sang Yong Seo, Dae-Gun Kim, Sang-Soo Lee, IP Media Service Division, Digital Home Development Department, Convergence BU., KT, 17 Woomyeon-dong, Seocho-gu, Seoul, 137-792, Korea, Tel: +82-2-526-6529, Fax: +82-2-526-6128, Email:
[email protected]
Abstract
one or two kinds of DBS due to the limited
We show practical implementation of interactive data
mono-connection, user must change channel to access
broadcasting services in IPTV over the NGN by
another particular DBS or it takes too long time to
adopting multi-connected multicasting with unicasting.
receive the consecutive information in many kinds of
Proposed implementation design method supports
DBS included channel.
many interactive data services in one channel without channel change.
In this paper, we will describe our implementation design of interactive data broadcasting service transmission and implementation results on building DBS over the NGN. Proposed design method has
1 Introduction As explodes the high-speed IP network such as
affinity to adopt multicasting transmission of satellite
NGN and progresses convergence between IP-based
and cable, furthermore integrates it with unicasting
communication and broadcasting area, demands for
transmission of internet to provide interactive data
bi-directional interactive high quality services are
services. Also, by separating the channel with inbound
increased. With this requests, several Triple Play
group and unbound group for the program linked and
Services (TPS) including telephone, internet and
supplementary services respectively, at the same time,
broadcasting appear to satisfy customer’s expectation
by dividing access method into multicasting and
[1]. Especially, in TV, using the high-speed return path,
unicasting for each general metadata and more
Data Broadcasting Service (DBS) [2] integrates audio,
specific information, we can overcome the previous
video broadcasting channels with interactive data of
problem and provide many kinds of DBS in one
the internet and telephone via T-information, T-communication,
channel without channel change.
T-commerce, T-entertainment, T-learning, etc. Now, there are several DBS providers such as satellite [3], cable, and Internet Protocol Television
2 Transmission method A. Multicasting with unicasting transmission
(IPTV). Unfortunately, due to the limit of the
We propose highly efficient data transmission
bandwidth of uplink as return path in satellite and
scheme of interactive DBS in IPTV over the NGN for
cable network, there are some difficulties for the
the seamless bidirectional data communication and
dynamic
audio, video channel services simultaneously using
and
seamless
DBS.
Meanwhile,
By
renovating the previous IP networks into NGN with
multicasting
Quality of Service (QoS) and combining broadcasting
proposal distributes the main frame and fixed
skill in a communication view, IPTV can provide
unidirectional audio, video channel with multicasting
bidirectional interactive DBS vividly. However,
and specific information according to the user’s
because previous multicasting method only includes
request with unicasting. When high simultaneity is
89-955301-4-6 98560
2006 OSIA
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with
unicasting
transmission.
This
As described in the figure 2, by linking up one channel out of many selective inbound audio, video program channels and joining continuously unbound multicasting channel at the same time, IP tuner of the STB organizes both various program supplementary data broadcasting services and audio, video program in one screen concurrently. When user selects one video channel and program supplementary service at the same time, video stream and basic application
Fig. 1. DBS flow diagram over IPTV
expected with or without random user request, multicasting is more effective than unicasting. On the other hand, when the user requests service randomly with interactive connection or the chance of simultaneous requests is low, unicasting reduces the traffic congestion and provide more diverse DBS to satisfy each person’s taste. Figure 1 shows an example of DBS flow diagram between the IP media platform and receiver.
frame are sent with inbound and brief information of the supplementary service is delivered with unbound group, finally specific interactive supplementary data is transmitted with the unicasting according to the user’s request. 3 Practical Implementation We implemented various data broadcasting services with interactive data of the internet and telephone as well as audio, video streaming. First, we will explain
B. Inbound group and Unbound group Distribution
We divided the previous unidirectional multicast channel into two multicast group with inbound group channel for the audio, video program including program linked application and unbound group channel for the program supplementary metadata, the service information (SI) data and Internet Media Guide (IMG) metadata such as Electronic Program Guide (EPG). Because the SI data in DBS of IPTV contains metadata of every content including the information of transport stream (TS) and service with events, if these are placed in the inbound group, it is very redundant to waste bandwidth of every connection. Therefore, separated unbound multicast group channel is more efficacious for the transmission
how to apply the ACAP [4] for the data transmission and management. Later, we will show three examples of practical implementation. A. Data Service in the ACAP
For the flexibility and stability of DBS transport protocol, we observe the Digital Storage Media Command and Control (DSMCC) user to user Object Carousel (OC) [5]. As showed in the figure 3-(a), we composed the directory and files according to the service category. Then broadcast each basic service frame and information regularly in the circular type with multicasting and deliver specific supplementary data
with
unicasting
method.
STB
refer
the
Application Information Table (AIT) and find control
of SI data.
Inbound Group
Unbound Group
Fig. 2. Multicast with unicast transmission
Fig. 3. (a) OC File System (b) AIT update mechanism
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message consequently. Finally parse these files and
including karaoke, game, stock and banking as a
display data in TV. Also, as shoed in the figure 3-(b),
program independent service.
when another request for other application comes up,
DBS system sends the basic frame and application
the AIT is updated. After parsing the new AIT, the
in the multicasting with the unbound group and
receiver stops previous application and starts newly
channel information via multicasting channel and
connected application.
transmits the event information with unicasting route
B. Practical Implementation Examples
through data server as described in above. When the
Figure 4 represents the practical implementation
user requests the SMS application at any time, the
examples of the interactive data broadcasting service
STB shows the application and prepare the return
in IPTV over the NGN. One is the main example
channel to communicate with other device via the
using the multicasting with unicasting transmission;
unicasting method. In the real service, the karaoke is
EPG. Next is T-communication such as messenger,
predicted as a killer application in DBS.
SMS,
mail,
channel
chatting
as
a
program
supplementary service and the final is data services
4 Conclusion and Future work In this paper, we showed how to design and implement the interactive data broadcasting service in IPTV over the NGN. The simultaneous use of multicasting and unicasting transmission method with inbound group and unbound group can support a lot of DBS in one channel without channel change to receive a particular service. This enhances the quality of the DBS and network bandwidth efficiency as well as user convenience. For future work, we plan to extend our
(a)
work to the more diverse service scenario which are connect to various device such as PDA, DMB, cellular phone and Wibro terminal in the wireless network. 5
References
1. Jangwoo Son, "Triple Play Service: Broadcast TV and VoD over IP", Netmanias Network Newsletter, Vol.1, No.1, Sep. 2003. 2. Edward M Schwalb, "iTV Handbook Technologies and standards", PTR, in New Jersey, 2004, pp. 25-60. (b)
3. Skinnernoen. H, Leirvik. R, Hetland. J, Fanebust. H, Paxal. V, "Interactive IP-network via satellite DVB-RCS", IEEE Journal on Selected areas in communications, vol. 22, no. 3. April, 2004. 4. ATSC Candidate Standard CS/101A, "Advanced Common Application Platform (ACAP)", 2004 5. ISO/IEC 13818-6, "Generic coding of moving pictures and associated audio information - Part 6: Extensions for DSM-CC", 1998.
(c) Fig. 4. (a) EPG (b) T-communication (c) Data services
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