Service Delivery within an IMS Environment

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.

As the next generation networks promise network convergence with services for both static and mobile networks, the research focus is converging towards standardizing a common infrastructure for all-IP networks. IP Multimedia Subsystem (IMS) is a recent initiative, which outlines a service delivery platform (SDP) framework. A flexible and robust QoS management system for IMS is essential to ascertain the achievability of service quality on these converged networks. As Triple and Quadruple Play services are the most celebrated services of IMS in the near future, the necessity of QoS assurance is becoming an imminent need of the hour. Multimedia services delivery in converged IP networks using IMS, concentrates on ensuring capabilities to ensure the best QoS. To meet these requirements, we have designed a set-top box which provides feedback in IMS management architecture to ensure end-toend QoS as well as enables the functionalities of Regional Gateway for the Home Network. Results of the simulation confirm the improvement of performance parameters and the quality of service.

Although the IP Multimedia Subsystem (IMS) and Web Serviceshave been developed on the basis of different Service Delivery Platforms (SDP), opportunities for new services have emerged from converged access to IMS and Web Services. Researchers are focusing on finding means to develop converged access architectures for IMS and Web Services while preserving the benefits they provide and not overburdening the end users' terminals. In this paper, we classify the existing converged access methods for IMSand Web Services into four categories, compare them and identify their drawbacks. To address these drawbacks, we have designed a hybrid thin client-based novel architecture for converged access to multimedia services provided by a combination of IMS and Web Services. The proposed solution limits the impact of platform heterogeneity and resources by relinquishing the complexity of signalling and session management to an intermediate virtualization server, which in turn acts as a client for network-based services.

The main stages of the historical development of telecommunication networks are shown. It is noted that today the most common concepts are NGN (Next Generation Network), supporting the functionality of Triple-Play Services (triple services – voice, video and data transmission), as well as IMS (IP Multimedia Subsystem), which combines cellular technology and landline communications. They are able to provide a wide range of services: basic, additional, intelligent. In addition, IMS is able to provide mobile services. The IMS architecture layers are presented – transport layer, control layer; layer of service and application servers. Particular attention is paid to the layer of service and application servers. Based on the analysis of ITU recommendations, the main telecommunication services quality indexes are determined, namely, the time of service provision, the length of the queue that the service request falls into to wait for service on the server, and the probability of refusing to provide services. Based on the proposed mathematical models of the NGN intelligent superstructure, analytical expressions are presented for calculating the quality indexes of intelligent services in NGN for one type of service and for K types of services, taking into account the self-similarity of traffic, and without taking into account. To evaluate the quality of services in IMS, it is proposed to use the approaches of queuing theory and tensor analysis. Tensor analysis offers a mathematical apparatus for transforming coordinate systems, considering IMS as a set of geometric objects whose projections are different in different coordinate systems, but the physical properties of the objects themselves do not change. Expressions are proposed that make it possible to calculate the following QoS indexes in IMS: average queue length, average residence time of an application in the system for all types of services in IMS. It is considered that the incoming traffic is the simplest. Further development of the work is to take into account the self-similar nature of traffic, which is created by the flow of requests for services that come to IMS, as well as the limitations of the server buffer, which will allow a more accurate assessment of the quality of services in IMS.

Todaypsilas user wants exciting new services at reduced costs. Legacy ldquovoicerdquo services are considered to be bare minimum. To satisfy their customers and be competitive, Telecom service providers are pressured to provide converged and differentiated services at reduced cost. IP multimedia subsystem (IMS) is touted to be next generation telecom architecture that enables service providers to achieve this requirement. IMS architecture allows service providers to offer a variety of multimedia services in the service layer. Service providers today are building an eco-system with partner vendors to offer new services in this layer. With the success of person-to-person and person-to-content services in the Internet world, it becomes more compelling for mobile device manufactures and service providers to reach out to developer community to create more innovative applications with IMS infrastructure. This paper describes how ldquoservice creationrdquo focus is being shifted from operators and mobile device vendors to third party developers. It explores the benefits of having a service creation platform to aid in developing such services. It outlines the elements of software development kit (SDK) which will help in maximizing productivity and enables developers to focus on creativity. This paper analyzes the need for a complete simulated setup for developers to create and test their services before deploying into real network. There are different service creation environments that are available like service delivery platforms (SDP), JAIN SLEE, and OSA/Parlay etc. In this paper the primary discussion is on the usage of standards based API in IMS/SIP SDK. It dwells more into JSR API for client development and application server development. It also touches upon how SIP SDK can be interfaced with Web 2.0 components.

Emergency Telecommunications (EMTEL) deal with provisioning of telecommunications services in emergency situations; these can range from an individual in a state of personal emergency (with need to make an emergency call due to sudden illness, traffic accident, fire) to a very broad perspective of serious disruptions (earthquakes, floods, terrorist attacks). EMTEL covers the telecommunications needs of public safety resources, like: police, fire–fighters, ambulances and other medical services: such services usually rely on dedicated networks and equipment. We realised PICO (control platforms and delivery of services in converged networks) a platform for service delivery and emergency management on public telecommunications networks. PICO platform leverages on application streaming on Android OS and a context–aware system for fixed–mobile convergence based on IP Multimedia Subsystem (IMS).

IP multimedia subsystem (IMS) is the core multimedia network in the next generation all-IP environment. It provides access independence for multimedia applications across fixed and mobile access networks. When a roaming IMS subscriber connects to IMS through mobile access networks, handover becomes a critical issue; this needs to be addressed. Since IMS concerns application layer handover for session mobility, the application layer handover takes a long time for recovering the suspended sessions according to the standard IMS session reestablishment procedure. This introduces noticeable service interruption to end users and cannot be tolerated for real-time applications. In this paper we propose a fast IMS service recovery mechanism to shorten the service recovery latency by combining the IEEE 802.21 Media Independent Handover service and the IRTF Media-Independent Pre-Authentication frameworks. The proposed mechanism performs the necessary IMS registration and QoS re-negotiation procedures in advance of lower-layer handover. Thus it reduces the service recovery latency for suspended services. With parallel design in time, the proposed mechanism is able to shorten overall handover relevant latency as well. Technical examination shows that it is easy to deploy the proposed mechanism in current multimedia service environments.

IP Multimedia Subsystem (IMS) is a novel architecture, which is the basis for the new network architecture for future mobile applications incorporating voice, video and many other multimedia services. It is also the ultimate goal for the development of ALL-IP network, which is supported and developed by China Mobile many other famous operators all over the world. IMS is an overlay network on top of IP that utilizes SIP (Session Initiation Protocol) as the primary signaling mechanism. Because of its IP based architecture, IMS faces many new security challenges both in core network layer and application layer. Therefore, this paper provides an overview of the IMS architecture and presents some researches and discussions on the relevant security challenges.

4G systems have been continuously evolving to cope with the emerging challenges of human-centric and machine-to- machine (M2M) applications. Research has also now started on 5G systems. Scenarios have been proposed and initial requirements derived. 4G and beyond systems are expected to easily deliver a wide range of human-centric and M2M applications and services in a scalable, elastic, and cost efficient manner. The 3GPP IP multimedia subsystem (IMS) was standardized as the service delivery platform for 3G networks. Unfortunately, it does not meet several requirements for provisioning applications and services in 4G and beyond systems. However, cloudifying it will certainly pave the way for its use as a service delivery platform for 4G and beyond. This article presents a critical overview of the architectures proposed so far for cloudifying the IMS. There are two classes of approaches; the first focuses on the whole IMS system, and the second deals with specific IMS entities. Research directions are also discussed. IMS granularity and a PaaS for the development and management of IMS functional entities are the two key directions we currently foresee.

IP Multimedia Subsystem (IMS) is an enabling technology that are designed to provide multimedia services over heterogeneous networks. In IMS based heterogeneous networks the placement of gateway plays a vital role in enhancing the Quality of Service (QoS) and the enhanced Packet Data Gateway (ePDG) is being considered in interworking. The ePDG is realized at the edge of the network where IP Multimedia Subsystem (IMS) interacts with Worldwide Interoperability for Microwave access (WiMAX). Also, the performance of network has been enhanced by allocating priorities to mobile Stream Control Transmission Protocol (mSCTP) on per stream basis. Hence the proposed interworking system considers the impact of IMS with mSCTP and ePDG. In this paper, the performance of the network has been evaluated in terms of throughput, delay and retransmission attempts and the performance comparison is made against the conventional Transport Control Protocol (TCP) over the same network conditions. The performance evaluation shows that the proposed QoS approach improves delivery of multimedia services over heterogeneous IP access.

A key advantage of the IP Multimedia Subsystem (IMS) is that it promotes the development of innovative multimedia services designed to bring an enhanced experience to the end user. The presenceand availability service is viewed as an indispensable feature for these next-generation services to help service providers generate new revenue and reduce churn. Numerous new services are currently being designed to take advantage of this feature. In this paper, we examine presence and availability in the context of IMS and describe its architecture as defined by the 3rd Generation Partnership Project/3rd Generation Partnership Project 2 (3GPP/3GPP2) and the Internet Engineering Task Force (IETF). In addition, we provide an analysis of presence updates and propose a user model and a traffic model to quantify the signaling traffic that such a feature can generate on a network. Through this model, network designers can examine the processing requirements for presence servers and other IMS components (i.e., call session control function [CSCF]) as well as the cost of transporting such traffic in the network.

The IP Multimedia Subsystem (IMS) is defined by the 3rd Generation Partnership Project (3GPP) as a new core network domain. IMS provides a service control platform that allows creation of new multimedia and multi-session applications utilizing wireless and wireline transport capabilities. In this paper we will cover the concepts and standards defining IMS and review the network architecture from a mobile perspective. We will see how IMS interacts with the Packet Switched Domain (e.g. Wireless LAN, GPRS, and UMTS networks), the Internet, and application services. Then we will examine the key IMS capabilities and show how they can be combined to create new mobile IP services. Finally, we present a software architecture, which is enabled by IMS and allows development of unique applications (with multimedia/multi-session functionality, single/multi-user, service to user). The software architecture is illustrated by an example of a prototype application.

Objectives: The IP Multimedia Subsystem (IMS) is an architectural framework for delivering protocol-based services that enables an easy deployment of new rich multimedia services mixing voice and data. In fact, the IMS is vulnerable to several malicious uses that can be conducted by its users. We propose in this paper, a security enhancement architectural model to monitor the system and build a rapid and normal functioning retrieval after failing. Methods/Statistical Analysis: The weakness of the IMS network topology structure makes it a target for both normal cellular threats and IP-related threats. We propose a model that consists of dividing a complex set of end-of-end (IMS-based) network security related features into separate architectural components, layers and tiers in order to divide the system and to be more precise in the problems’ detection phase. Findings: Using the proposed approach, an effective evaluation study is investigated. The simulated network adopting our model showed an excellent behavior. The quality metric measuring call quality showed some excellent results. In other words, the adoption of the proposed model does not affect the normal frame delays, packet arrival durations and packet loss rates. The results showed how our proposed model is lightweight and effective in handling security issues. Application/Improvements: This paper fulfills a huge need of handling security using an effective lightweight architectural model adopting the proposed approach. Our methodology ensures designing a secure, flexible and easily monitored network with a rapid location of the affected areas and effective security supervision.

With the emergence of converged networks, circuit switched (CS), packet switched (PS), and IP Multimedia Subsystem (IMS) domains and application servers (AS) are now merging to combine all kinds of services, business modes, and network architectures. This can cause chaos among various charging mechanisms within the networks. This paper presents a common charging controller function (CCCF) between the charging trigger function (CTF) of individual network elements (NEs) and the charging system. The CCCF operates with the common NE-independent charging control layer to serve various network elements in CS, PS, and IMS domains and application servers. It also simplifies NE-dependent CTFs for accounting metrics collection (AMC), regardless of whether the charging mechanisms are online or offline. The CCCF maintains a single charging characteristic database that stores the charging mechanism of each subscriber's service usage and forwards subscriber accounting data to the charging systems. By including the CCCF in networks, the IMS and pre-IMS charging systems for existing and new customers can be integrated without replacing deployed products, resulting in significant cost savings for telecommunications vendors and customers.

Due to Internet Protocol (IP) is the most important protocol in Next Generation Networks. 3GPP utilizes Session Initial Protocol (SIP) based on IP as the base protocol for negotiating sessions in IP Multimedia Subsystem (IMS). Different from traditional circuit-switched network, the media traffic and signaling are delivered through IP transport layer in IMS. The media traffic may affect the signaling efficiency in core network because the traffic collisions and delivery packets in best effort. This paper proposes a novel path-migration mechanism for enhancing the traffic efficiency in IMS. The simulation results show that by adopting proposed path-migration mechanism, the interference and traffic collision can be reduced and the signaling efficiency in core network can be improved.