Service Delivery Platform Architecture for the Next-Generation Network
Hiroshi Sunaga, Yoji Yamato, Hiroyuki Ohnishi, Masashi Kaneko,
Masami Iio, and Miki Hirano
NTT Network Service Systems Laboratories, NTT Corporation
3-9-11 Midori-cho, Musashino-shi, Tokyo 180-8585, Japan
Abstract platform is expected to play an important role in the
This paper describes an advanced service delivery NGN and so we have developed a prototype.
platform (SDP) that is expected to be used in the Next This paper is organised as follows. In the next
Generation Network (NGN). To meet diverse demands section, the basic approach to establish our SDP
from NGN customers, it is very effective to integrate architecture is presented. Then, Sec. 3 deals with major
state of the art technologies beyond the boundaries of capabilities required for the SDP on the NGN and Sec.
technical domains, such as the telecommunication, 4 covers ubiquitous context-aware communications
enterprise, and Internet fields, to enrich services and -. Next, in Secs. 5 and 6, we show a service
mash-up simple service elements into unlooked-for creation and propagation mechanism and example
values. We use the service oriented architecture (SOA) applications. Finally, we conclude the paper.
concept as the basis and extend it to ease the creation
of customised or personalised services. Context-aware 2. Basic approach
dynamic binding of service components, finer-grained Considering that Web 2.0 is gaining a foothold in
SIP call handling, and execution control for advancing the Internet, telecom operators should
guaranteeing the service level agreement are main provide Web2.0-related services over their NGNs. The
features of our platform. This is expected to play an major concepts of Web 2.0 are the provision of
important role in the NGN or ubiquitous attractive services that meet various and specific (long-
communication environments. tail) customer demands, a framework where users act
as co-developers or contributors, and a fully
1. Introduction component-oriented nature.
In the years to come, integrating state of the art Our SDP is aimed at easy and quick creation of
technologies beyond the boundaries of technical Web-telecom coordinated services by mashing-up
domains, such as the telecommunication, enterprise, components accessible through networks, e.g., the
and Internet fields, will become more important. From NGN, the Internet, or sensor networks, and
telecom carrier viewpoints, coordination with Web and propagating them smoothly . We take an abstract-
Internet technologies will become very effective for scenario-based service composition approach for long-
enriching services in the next generation network tail or personalised service mash-up at a low cost.
(NGN). To integrate these domains, the service Although the basic mash-up method is provided by
oriented architecture (SOA), originally developed for vendors, we add context-awareness to it as described
enterprise networks, can be a basis. in Sec. 4.
We use this concept as the basis and extend it to Because our abstract-scenario-based mash-up is
ease the creation of customised or personalised easily learned, third parties can participate in the
services that will be required in the NGN and service creation and/or provision as contributors. Even
ubiquitous communication era. Context-aware ordinary people can contribute to this service creation-
dynamic binding of service components, finer-grained provision cycle. In conjunction with the NGN’s QoS
SIP call handling, and execution control for guarantee and solid authentication capabilities,
guaranteeing the service level agreement are specific services can be provided more comfortably and
features of our service delivery platform (SDP). This securely than on the Internet. Also, the service level
agreement (SLA) can be guaranteed.
3. Configuration of proposed SDP 3.2 Enablers
3.1 Overview We introduce a SIP session control enabler, a media
The service control positioning in the NGN is handling enabler, and a context handling enabler over
described in the IP Multimedia Subsystem (IMS) the NGN to abstract and offer network-related
standard as shown in Fig. 1. Although requirements capabilities in the form of well-defined and
are discussed, the precise SDP configuration is not standardised interfaces. Most SIP enablers provide
defined. Therefore, major vendors are currently Parlay-X session-handling interfaces, but we define
developing their own SDP products based on their more elemental application programming interfaces
concepts. (APIs) as shown in Fig. 3.
Web portal Element management system
Parlay app. Support systems
Parlay GW SIP app.
SIP app. make call switch call split call join call
Service broker (SCIM)
end call GetCallinformation
S-CSCF BGCF Centralised database
P-CSCF MRFC Fig. 3 Our proposed APIs
node Media server Session border
controller PSTN and Legacy GW Because the granularity of Parlay-X is rather large
Access network PSTN (e.g., the unit of three-way calling or a conference call),
we introduce a set of basic operations that can be used
BGCF: breakout gateway control function MRFC: media resource function controller in any combination . Our APIs can not only be used
HSS: home subscriber server P-CSCF: proxy call session control function
I-CSCF: interrogating call session control function S-CSCF: serving call session control function independently, but also as attachable components to
Fig. 1 NGN functional blocks defined in IMS enhance Parlay-X based enablers. Also, the media
handling enabler provides finer-grained media control
However, they have basically the same architecture. capabilities for service coordination to service
An orchestration server controls the coordination of providers that cannot provide an expensive media
components and enablers abstract the underlying server by themselves .
telecommunication network capabilities as shown in Based on our APIs, we can create and provide a
Fig. 2. Our SDP uses this basic architecture but some differentiated service as shown in Fig. 4. This is a call-
specific values are added. First, it places the SCIM centre application. First, a customer asks operator A
block between the NGN and SDP as defined in the something. The original connection is split into two by
IMS standard (Sec. 3.3). Then, it also provides the SplitCall interface, one for between the customer
capabilities for facilitating context-aware and the guidance server, and the other for between
communication in the forthcoming ubiquitous era or operator A and the expert (operator B). After a
for activating the service creation cycle (Sec. 4). conversation between the two operators, a connection
between the customer and operator B is established by
Orchestration Coordination of service
using the JoinCall interface. If a current Parlay-X
Coordination & components interface is used, the call is disconnected once during
execution cntl. (BPEL-based & abstract
Network abstraction context-aware scenario) the reestablishment procedure.
flexible interface for
Service bus WS (1)
Enablers Customer Operator A Customer Operator A
Enabler Enabler Enabler server server (2) SplitCall (2) (2)
SIP media context/ JoinCall
NGN The Internet
Multiple technical Enterprise net Operator B Operator B
domain coordination WS: Web Services (announce) (announce)
Fig. 2 Common configuration of SDPs Fig. 4 Differentiated service based on our enablers
The context/presence enabler provides Web
Services-based user context APIs by converting
presence information managed in the underlying - Ubiquitous scenario translation: see Sec. 4.
network, location servers, or sensor/intelligent We basically use off-the-shelf products for the
transport system (ITS) networks. service bus and BPEL engine parts, but we have
devised and prototyped special elements for the
3.3 SCIM execution control and ubiquitous handling. In
As defined in the IMS standard, the Service particular, the priority control of the packet flow in the
Capability Interaction Manager (SCIM) function block bus is a key to guaranteeing the SLA, and ubiquitous
is necessary to control SIP messages between the context-awareness will enhance personalised-service
network and enablers. In our architecture, the SCIM creation.
can be included if desired . The SCIM distributes For the execution control, we introduce the concept
messages to appropriate destinations based on of Policy Evaluation, Enforcement and Management
customer profiles or SIP parameters, blocks (PEEM), one of the policy enforcers standardised in
inconsistent messages, relays messages between the Open Mobile Alliance (OMA). Considering the
Application Servers (ASs) and enablers, and controls performance, we prototyped a proxy type system (Fig.
service contention. 6), where our orchestration server performs single-
Because most service control messages pass the sign-on authentication by the user identifier (ID) and
SCIM, the performance is one of the major items to be authentication ticket contained in the request, converts
solved. One approach is the use of carrier-grade the ID in accordance with the designated service,
middleware and the C language, but it is not easy to controls traffic, and transfers the request. In addition, it
add or change new service logic. Therefore, we guarantees the SLA by observing the response time.
currently think that the use of an off-the-shelf SIP Orchestration Server
Servlet product as the core protocol handling part for User/Service Information Repository
this block as well as for the SIP session enabler is
effective. Its use gives programmers a Java-based easy
software development environment, but several Access control
countermeasures are required against, for example, the (1) Login (UserID, PWD)
Flow control) (SLA
garbage collection (GC) procedure. Ordinary Java (2) Authent. ticket
virtual machines allow the service stoppage by GC, Data transmission
and so GC-free products should be selected. Service request
(input message + authent. info.*) Message proxy function
Requestor * authent. ticket & password
(service app) Components
AS enabler Fig. 6 Execution control
AS To support service creation, development, and
AS SCIM service provision, we have also devised a development
environment that supports service creation for
CSCF Coordinates application developers, i.e., a graphical service creation support
NGN service runtime
execution between tool  and a wrapper tool that converts interfaces
multiple enablers or ASs.
between ordinary Web pages (HTML) and Web
AS: application server, CSCF: call session control function Services . Basically, the SOA-based framework
requires a standardised interface for invoking
Fig. 5 SCIM positioning
components, i.e., the Web Services interface, but this
tool allows ordinary Web applications written in
3.4 Orchestration server HTML to be used as components.
The orchestration server consists of a service bus
that efficiently connects all the elements and a
coordination server that includes the following
4. Towards ubiquitous SOA
capabilities . We regard context-awareness as the key software
- BPEL engine: executes scenarios for service technology in the ubiquitous era. We have established
coordination. a context-aware service composition framework ,
- Execution control: guarantees secure service and we provide it as an advanced service. In this
coordination by providing SLA, authentication, and framework, the service scenario is described in a more
supervision capabilities. abstract format than BPEL. BPEL requires specific or
exact component names and parameters for invocation as the development section of an operator. In addition,
as a C-language function-call, but in our case, billing and settlement capabilities are offered to
abstractly described process names in a scenario are support the activities of third parties.
translated at runtime and the most appropriate Users can use various enriched or personalised
components are selected and invoked in accordance services over a safe and high-throughput network, i.e.,
with user context. For this purpose, every component the NGN. Operators can create various
is given a semantic description by the OWL-S standard enriched/personalised services quickly and cost-
, and the engine translates the process name into an effectively because anyone, even ordinary people, can
exact component that meets the user context. participate in creating/providing their own services.
For example (Fig. 7), if we describe a scenario in From the viewpoint of third-party service providers,
which a user’s schedule is retrieved from the scheduler telecommunication-specific capabilities such as
and the user is notified of route search results, the telephone handling, security management, and
sequence of “schedule retrieval”, “route search”, and bandwidth control are effective as components to build
“user notification” category names is translated into a one’s own Web-telecom coordination business even if
set of exact components and each component is the provider does not precisely know complicated
invoked. Differences in parameters are adjusted by specification or procedures about telecommunication
checking their Web Services Definition Language capabilities.
(WSDL) definitions, and a SOAP message is parsed
and exchanged. 6. Applications
There are two approaches to create applications
Orchestration Server just-in-time
over the SDP. One is to enhance the basic voice/video
call session by adding Web or enterprise components.
invocation This is similar to the Advanced Intelligent Network
(AIN) services. The other is to trigger a voice/video
selected according selection selection selection invocation call session from a Web or enterprise application.
service database Internet developers, or even ordinary users, can easily
participate in this type of approach. The main target of
service propagation discussed in Sec. 5 will be this
recorded in New mail IM
schedule retrieval root search
category category newly registered
An example of the first approach is shown in Fig. 9.
component can be used
The basic videophone communication service is
In accordance with user context,
enhanced by composing Internet components such as
component is dynamically commercial (CM) content, merchandise information,
word-of-mouth (WOM) information, media mixer
Web-based Components (Web Services (WS)) (media enabler), and electronic commerce (EC) sites.
In addition, the SIP adaptor conceals complicated SIP
call control procedures so that existing EC sites can
operate on the NGN.
Fig. 7 Context aware service coordination The example shown in Fig. 10 is of the second
approach. If there are components such as an OA
5. Activation of Coordinated Service scheduler, a text-to-speech device, and a SIP session
Creation and Propagation control enabler, we can create a service that informs
An overview of the future network service the user of the schedule by an artificial voice through
distribution environment based on our platform is an automatically set-up call.
shown in Fig. 8. Elementary service components of Of course, many other service applications can be
telecommunications, enterprise network, Web, and proposed, and we have prototyped several ones.
sensor network domains can be composed by a service Because the context aware mechanism allows us to
scenario that describes the sequence of components (or designate an abstract process name instead of a
categories) to be invoked, usage conditions, and particular action (function call), a current service
exchanged parameters. Once a service has been created, application can be easily modified by replacing the
it can be used as a basis for other enhanced services by existing component with a new one belonging to the
adding new components or scenarios. This framework same category. This helps to effectively develop
will be used by third-party venture companies as well service applications.
7. Conclusion services. Context-aware dynamic binding of service
We showed an advanced service delivery platform components, finer-grained SIP call handling, and
for the NGN. This platform is based on state of the art execution control for guaranteeing the service level
technologies beyond the boundaries of technical agreement are main features of our platform. These
domains, i.e., the telecommunication, enterprise, and features help us to create more attractive enriched
Internet fields, to enrich services and mash-up simple service capabilities and activate the NGN business
service elements into unlooked-for values. In addition, scene more than those of major vendor products. Our
we used the SOA concept as the basis and extended it platform is expected to play an important role in the
to ease the creation of customised or personalised NGN or ubiquitous communication environments.
operator’s development unit vendors Third Party anyone
A B C D X Y Z
P Q R S K L M N
A B C L M N customisation by
Distribution of applications or components a user
novel services through composition context-aware personalization/customization,
quick provisioning P q R s
[rich and various components]
presence, alarm, data gathering, 3PCC, change call, split call, scheduler, business search, time table, translation, weather report,
traffic info., home electronics interruption, bandwidth change, VPN mngmnt., business apps., reservation, EC，game, music/video content, virtual reality service, agents,
control, … setting, blockage, service ordering… groupware,… blog, BBS, CGM，… …
Sensors/devices Telecom enablers Enterprise components Web apps. Web services Components to appear in future
Service Delivery Platform (ubiquitous SOA platform)
virtual reality, second lives
Web apps. content, Web
session control, media handling, Services agents, avatars, AI
operation/management enterprise business apps.
sensor networks, tags,
Fig. 8 Service creation and delivery by using our service delivery platform
Existing EC sites SDP (3) Appropriate CM/WOM info is WOM info.
searched for according to user WOM info.
(servers) can be orchestration server preferences
easily transferred scenario Internet
to NGN. Merchandise
ＣＭ server info.
Ｗｅｂ Ｗｅｂ info.
Ｗｅｂ Ｗｅｂ Enablers (moving picture)
Authent. Call control Scenario is easily
SIP adopter enhanced by adding
(5) When moving to
(6) User can EC sites, system NGN
authenticates user. (2) Videophone-CM ---components
enjoy secure EC
scenario is triggered.
shopping. (4) Web advertisement content is Web-Telecom
mixed/displayed on the videophone. coordinated scenarios
UNI can be easily
(1) Videophone call composed.
User A User B
Fig. 9 Application example 1 –SIP video call service with Internet content
based on context call control
Voice data 3
call control parameters
(a) VoIP call is set up
text 1 at scheduled time
Text-to-speech 2 text (schedule) and text is read out.
(media server) orchestration
Example scenario (b) right-click
person’s name and select
<invoke name="CybozeSE" operation="getLastMsg" />
<from = “mySchedule" />
<to variable = "text" />
</copy> --- components
<invoke name="TextToVoiceSE" operation="convertTextToVoice" />
<invoke name="MakeCallSE" operation="makeCall" />
Fig. 10 Application example 2 – Scheduler with SIP voice calling
References  M. Nakajime et al., “SIP Servlet Dialogue Handling for
 H. Sunaga, M. Takemoto, Y. Yamato, Y. Yokohata, Y. NGN Service Capability Interaction Manager”, IEICE
Nakano, and M. Hamada, "Ubiquitous Life Creation through APSITT2008
Service Composition Technologies", WTC2006, May 2006  T. Moriya, H. Ohnishi, M. Yoshida, and M. Hirano,
 H. Ohnishi, Y. Yamato, M. Kaneko, T. Moriya, M. “Dataflow Generation for Service Composition to
Hirano, and H. Sunaga, “Service Delivery Platform for Incorporate Web and Telecommunication”, IEEE
Telecom-Enterprise-Internet Combined Services”, IEEE Globecom2007, pp. 118-123, November 2007
Globecom2007, pp. 108-112, November 2007  Y. Nakano, Y. Yamato, M. Takemoto, H. Sunaga,
 Y. Yamato, and H. Sunaga, "Context-aware Ubiquitous "Method of creating web services from web applications",
Service Composition Technology", CONFENIS 2006, pp. IEEE International Conference on Service-Oriented
51-61, April 2006 Computing and Applications (SOCA)2007, June 2007
 M. Kaneko et al., “Novel SIP Session Handling in a  Y. Yamato and H. Sunaga, "Context-Aware Service
Service Delivery Platform for Telecom-Web Integration”, Composition and Component Change-over using Semantic
IEICE APSITT2008 Web Techniques", IEEE ICWS 2007, July 2007
 M. Irie et al., “Highly Flexible Media Handling Enabler  W3C, “OWL Web Ontology Language for Services
for the NGN Service Delivery Platform”, IEICE (OWL-S)”, http://www.w3.org/Submission/OWL-S/