Open Service Access Research Articles

Toward open service access to policy and charging control in evolved packet system

The emerging multimedia communications are expected to enable simultaneous services with high throughput and low-latency requirements. Ensuring appropriate quality of service (QoS) for multimedia services is one of the challenges that network operators have to cope with in the Evolved Packet System (EPS). The mechanism which allows policy based authorization and usage control of QoS resources intended for multimedia traffic in EPS is called Policy and Charging Control (PCC). The paper investigates the capabilities for open access to PCC. The open access allows third party applications to access functions in the telecommunication networks through Application Programming Interfaces (APIs). The support of standardized APIs for PCC is evaluated. An approach to design new APIs for PCC is described. APIs implementation issues are addressed including interface-to-protocol mapping. The functional verification of application server for open access to PCC functions is formalized. The application server's functional behaviour is modelled and adaptive load control mechanism is proposed. The application server performance and utilization are evaluated.

Towards a scalable mobile telemetry system and ubiquitous access to measurements

The paper presents a systematic approach to mobile telemetry and ubiquitous access to measurements data. A scalable functional architecture for mobile telemetry and secured open service access to data set is suggested. The focus is on identification of generic functions of mobile telemetry and definition of abstraction in a form of Application Programming Interfaces (APIs). The mobile telemetry system relies on Internet Protocol (IP) connectivity and it is access network and transport protocol independent. The reliable asynchronous communication is provided by the use of the transaction concept. Security services for access to the measurements repository are designed covering both mobile telemetry functions and accessibilities of external applications. As a use case of mobile telemetry application we consider air quality monitoring and propose a modified carbon dioxide information model. The proposed web services allow external applications to fetch measurements data in a secured and managed manner.

Design of Transparent Distributed IMS Network: Security Challenges Risk and Signaling Analysis

The IP Multimedia subsystem (IMS) based on SIP as mechanism signalling and interfaces with other servers using OSA (Open Service Access) and CAMEL (Customized Applications for Mobile network Enhanced Logic).Is responsible for the interconnection of IP packets with other network, IMS support data communication services, voice, video, messaging and web-based technologies. In this work we present a distributed design of architecture that turns up some challenges of transparent mobility on the secured IMS architecture. We introduced the architecture with clustering database HSS and automatic storage of data files that give a secure access to database. This paper gives an overview of classification of security in IMS network and we show delay analysis comparison in signalling interworking with and without securing Gateway (SEG) in the registration of any UE in access network based IMS. We show that there is a tradeoff between the level of increasing system security and the potential delay incurred by mobility in Access Network .we conclude that this architecture is suitable for operators and services providers for the new business models delivering ,the services based IMS Everywhere, anytime and with any terminals.

Development Approaches of Smart Space Service Components for Service Robots

Aiming at the application requirement of service robots,a smart space service component system supporting and enhancing the functions of robots is designed by introducing component-based development(CBD) methods.Basic structures and interaction modes are proposed for service components,based on which cross-platform service invocation is realized for robots.As a result,the problems of the assistant resource's diversity and heterogeneity can be resolved effectively. Service component encapsulates the assistant functions of resources into shared service and provides open service access and invocation on smart space's communication network through contractually specified service interface and description.It supports independent deployment,and is subject to third-party composition.Starting from assistant resources and clients for service robots,the principles of developing service components and service invocation programs by applying web service (WS) middleware technique,are presented in detail,and finally,they are proved by typical experiments.

Third party application control on quality of service in IP based multimedia networks

The paper investigates the capabilities for open access to resource management in convergent networks. Based on the analysis of policy and charging control functions in Internet Protocol Multimedia Subsystem (IMS), requirements for third party application control on quality of service (QoS) are identified. The functionality of Open Service Access (OSA) and Parlay X interfaces is evaluated for support of dynamic QoS control. An approach to design of OSA compliant application programming interfaces to QoS management in IMS networks is presented. The interface methods are mapped onto the messages of network control protocols such as Diameter and Session Initiation Protocol (SIP). The application view of authorized QoS resources for SIP session is modeled. Implementation issues concerning behavioral equivalence of the authorized QoS resources model and SIP session state model are discussed.

A Novel Strategy for Load Balancing of Distributed Medical Applications

Current trends in medicine, specifically in the electronic handling of medical applications, ranging from digital imaging, paperless hospital administration and electronic medical records, telemedicine, to computer-aided diagnosis, creates a burden on the network. Distributed Service Architectures, such as Intelligent Network (IN), Telecommunication Information Networking Architecture (TINA) and Open Service Access (OSA), are able to meet this new challenge. Distribution enables computational tasks to be spread among multiple processors; hence, performance is an important issue. This paper proposes a novel approach in load balancing, the Random Sender Initiated Algorithm, for distribution of tasks among several nodes sharing the same computational object (CO) instances in Distributed Service Architectures. Simulations illustrate that the proposed algorithm produces better network performance than the benchmark load balancing algorithms-the Random Node Selection Algorithm and the Shortest Queue Algorithm, especially under medium and heavily loaded conditions.

Open Access to Control on Quality of Service in Convergent Networks

This paper investigates the capabilities for open access to quality of service management in convergent networks. Based on the analysis of requirements for policy and charging control in Internet Protocol Multimedia Subsystem (IMS), functions for quality of service (QoS) management and charging that are available for third party applications are identified. The functionality of Open Service Access (OSA) and Parlay X interfaces is evaluated for support of dynamic QoS control, while an approach to development of OSA compliant application programming interfaces for QoS management in IMS networks is presented. The interface’s methods are mapped onto the messages of network control protocols such as Diameter and Session Initiation Protocol (SIP). Finally, aspects of interface implementation are discussed including behavior equivalence of state machines.

Open Access to Resource Management in Multimedia Networks

The paper is dedicated to mechanisms for open
 access to resource management in the Internet Protocol (IP)
 multimedia networks. First we present the concept of IP
 Multimedia Subsystem (IMS) and explain the IMS functional
 architecture, principles of quality of service management and
 service control in IMS. Then we describe the idea behind the
 opening of network interfaces for third parties so that others
 besides the network operator can create and deploy services.
 Open Service Access (OSA) and Parlay appear to be the
 technologies for value-added service delivery in multimedia
 networks. In the paper we take a closer look to the
 Parlay/OSA interfaces that allow third party applications to
 access the resource management functions in IMS. OSA
 "Connectivity Manager" interfaces and OSA "Policy
 Management" interfaces are considered. Parlay X Web
 Services interfaces provide a higher level of abstraction than
 Parlay/OSA interfaces and gain an amazing amount of
 support among service developers. We address "Applicationdriven Quality of Service" Parlay X Web Service and
 "Policy" Parlay X Web Service also.

An OSA service capability server for mobile services

PurposeThis paper aims to propose an open service access (OSA) service capability server (SCS) architecture that supports the network capabilities to the Application Server (AS).Design/methodology/approachBased on this architecture, the service capability feature (SCF) provides the OSA Application programming interface functions by implementing the SCF service logic module and callback module. The SCF uses the XML communication module to interact with service capability (SC), which is the bearer to realize services by implementing the SC service logic module. The SC service logic interacts with mobile core network through the session initiation protocol (SIP)‐based session control module and the SIP Callback module.FindingsThe push to talk over cellular service is used to illustrate how the proposed OSA SCS interacts with the AS and the mobile core network elements.Practical implicationsIn the design, when implementing a new service (i.e. to create a new SCS), one only needs to create the Callback module and the Service Logic modules, and other SC/SCF modules can be reused.Originality/valueThrough this modulized SCS design, the OSA service deployment can be speeded up.

Node Status Algorithm for Load Balancing in Distributed Service Architectures at Paperless Medical Institutions

Service architectures are necessary for providing value-added services in telecommunications networks, including those in medical institutions. Separation of service logic and control from the actual call switching is the main idea of these service architectures, examples include Intelligent Network (IN), Telecommunications Information Network Architectures (TINA), and Open Service Access (OSA). In the Distributed Service Architectures (DSA), instances of the same object type can be placed on different physical nodes. Hence, the network performance can be enhanced by introducing load balancing algorithms to efficiently distribute the traffic between object instances, such that the overall throughput and network performance can be optimised. In this paper, we propose a new load balancing algorithm called "Node Status Algorithm" for DSA infrastructure applicable to electronic-based medical institutions. The simulation results illustrate that this proposed algorithm is able to outperform the benchmark load balancing algorithms-Random Algorithm and Shortest Queue Algorithm, especially under medium and heavily loaded network conditions, which are typical of the increasing bandwidth utilization and processing requirements at paperless hospitals and in the telemedicine environment.

An OSA application server for mobile services

Purpose – Open service access (OSA) is a flexible and efficient approach for mobile service deployment. In OSA, network functionality offered to application servers (ASs) is defined by a set of service capability features (SCFs). The AS implements services by accessing the service capability through the standardized OSA application programming interface.Design/methodology/approach – The paper shows how the AS provides services by integrating the services supported by the SCFs. Then it uses the OSA mutual authentication and the push to talk over cellular service to illustrate the interaction among the AS modules and how the AS interacts with the framework and the SCFs.Findings – With this environment, the service developers are not required to access the details of the underlying mobile network, and thus the service deployment can be sped up. The purpose of this paper is to propose an AS architecture.Originality/value – This paper proposed an OSA AS architecture. Based on this architecture, a new applicati...

A vulnerabilities analysis and corresponding middleware security extensions for securing NGN applications

International standard bodies such as the Parlay Group, 3GPP (Third Generation Partnership Project), and ETSI TISPAN describe an applications middleware in the form of open service access (OSA)/Parlay Application Programming Interfaces and Parlay X Web Services which allow multimedia applications to be implemented on top of different fixed and mobile network types. These established middleware services are also applicable to the new IP Multimedia Subsystem (IMS) forming the heart of emerging next generation networks. The main objective of this kind of middleware services is to simplify and unify service creation and - as applications are realized in so-called application servers which can be flexibly connected to dedicated network gateways - also to expose available network capabilities to third parties. This results in an inherent increase of security threats and increases the risk of attacks on network resources. This article describes the security requirements and challenges to Web services-based NGN middleware. Based on this analysis the paper presents the middleware security mechanisms at application level providing end-to-end security based on standard such as XML Digital Signatures, XML Encryption and SAML (Security Assertion Markup Language). Furthermore, we propose additional security means in the form of intrusion detection and prevention (IDP) system protecting applications middleware against SQL injection attacks which are not mitigated by existing solutions.

CCL OSA: a CORBA-based open service access system

Open Service Access (OSA) is a flexible and efficient approach for mobile service creation and deployment. OSA allows network operators and enterprises to increase revenues via third party applications and service providers. In OSA, network functionality offered to applications is defined by a set of Service Capability Features (SCF). Services can be implemented by applications accessing the Service Capability (SC) through the standardised OSA Application Programming Interface (API). This paper designs and develops a Common Object Request Broker Architecture (CORBA) based OSA system. We show how OSA API interfaces and functions can be implemented by CORBA clients, stubs, servants and skeletons and how CORBA POA and ORB are set up for our OSA implementation. Then we use the authentication procedure for initial access to illustrate how CORBA mechanism works for our OSA implementation.

Service control for next-generation applications in wireless IP multimedia networks

Within the 3rd Generation Partnership Project (3GPP), the thrust of the session initiation protocol (SIP)-based Internet protocol (IP) multimedia subsystem (IMS) is envisaged to allow a swift progression towards the provision of multimedia applications for increasingly demanding end users. The paradigm of service programmability using open network application programming interfaces (APIs), with open service access (OSA) as its main exponent, is helping to drive this development together with the use of SIP. The focal point of this paper will be the multimedia services architecture in the IMS by providing details of the interaction of the IMS and the application servers in the form of the OSA gateway and the SIP application server. The paper aims to assess the value of the IMS service control (ISC) interface on application server interaction in the IMS. The paper will provide an OSA application use case, and will also present the presence server as an example of a SIP application server that fits in with the IMS. © 2003 Lucent Technologies Inc.

The Parlay proxy manager-Architecture considerations

The Parlay/OSA standards enable service providers to safely expose, in a regulated manner, pre-packaged network service capabilities to a large body of external third-party application developers. The objective is to facilitate the rapid development and deployment of new applications that could significantly enhance the end-user experience and improve the revenue-generating potential. The Parlay/OSA model supports service sessions to permit client applications to connect to various services hosted by a Parlay or open service access (OSA) gateway. Framework services may be configured to enable a suitable distribution of load at a session level granularity among the various service instances. Finer granularity of request distribution and more reliable end-to-end service access may be achieved through support for proxy manager architectures. In this paper, we present schemes for load distribution and higher reliability, and proxy manager architecture alternatives. We then further extend the proxy concept to application mediation and cross-protocol, cross-domain service reuse. © 2003 Lucent Technologies Inc.

Service mediation standards

The trend in service standardization has moved away from specifying individual services, via the classification of service toolkits, to the concept of defining a service mediation architecture. The prime objective of service mediation is the proliferation of innovative end-user applications by means of network transparency and abstracted network capabilities. This implies requirements alignment and also dependencies and harmonization between various involved standards bodies. This paper addresses the impact of these implications, as well as the latest developments and directions in service mediation standards and why and how these are different from traditional standards with respect to issues like conformance and backwards compatibility. The paper homes in on Parlay and Open Service Access (OSA) in particular and looks at how Parlay/OSA capabilities are evolving and how they relate to the Web Services model. The recent embracing of JAIN <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">∗</sup> and Web Services Definition Language (WSDL) as technology realization of the common Parlay/OSA interface definitions are also discussed. © 2003 Lucent Technologies Inc.

Web services in third-generation service platforms

In third-generation (3G) networks, third-party service developers will have access to the mobile network resources using open network interfaces, such as the 3rd Generation Partnership Project's (3GPP's) Open Service Access (OSA). The service platforms that offer these interfaces provide interoperability, third-party access, and ease of use, which goes beyond the capabilities of existing intelligent network technologies. OSA is usually implemented using CORBA <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">∗</sup> object middleware. To accommodate a broad community of developers and scenarios of deployment, middleware technologies other than CORBA should be supported as well. In this paper we discuss Web services, an emerging Extensible Markup Language (XML)-based middleware technology that is especially targeted at the Internet community. We describe the technical benefits of both Web services and CORBA in an OSA context and look at the main issues and possible solutions with respect to offering Web services-based access to the OSA interfaces. We also describe a prototype to validate our conclusions.

HotTown, enabling context-aware and extensible mobile interactive spaces

This article introduces a novel, open, and scalable service architecture for context-aware personal communication. In contrast to the network-centric open service access in third-generation mobile networks, this architecture moves the point of integration for user services out to the mobile devices, where we can create support for context-aware computing and communication. Support for peer-to-peer service negotiation with minimal a priori shared knowledge, context representation, and reasoning about context enables the mobile agents (that represent users and other entities) to be aware of and react to any event and thus context. Hence, the delivery of context-aware applications to users intertwining digital and physical objects in mobile interactive spaces leverages events from sensors, mobility support, and digital entities. Finally, a presentation of our prototype and experiences from the HotTown project demonstrates the feasibility of the approach and provides some examples of the enabled user communication for large-scale mobile networks.

The support of mobile internet applications in UMTS networks through the open service access

Third-generation wireless networks are expected to enable the mobile Internet to become a reality, offering fast Internet access and high-speed data services to mobile subscribers. For network operators to allow for the rapid development of innovative value-added applications on the scale seen in the Internet today, the wireless core network needs to be opened up for third-party applications provided by independent software vendors (ISVs). The Third-Generation Partnership Project (3GPP) is currently working on the production of technical specifications to provide a mechanism that would permit ISVs a standard interface to access network capabilities traditionally available to network operators. Within 3GPP, this mechanism is commonly referred to as the open service access (OSA). This open service access is predominantly targeted at Universal Mobile Telecommunications System (UMTS) networks, allowing application developers to access the feature-rich core network capabilities. This open access enables network operators to offer innovative services to their subscribers allowing the ability to differentiate themselves in a competitive market. With the imminent commercial deployment of the General Packet Radio Service (GPRS), existing fixed-line Internet service providers (ISPs) can now offer mobile Internet to end users in a UMTS environment where the responsibility of the network operator is reduced to providing IP connectivity. The increased competition from ISPs poses a big threat to the revenue stream of the network operator. This paper explores the possibilities of OSA to facilitate network operators in providing the mutual support of network capabilities and Internet content. These possibilities would allow the network operator to become a value-added mobile Internet service provider (VAM-ISP).3