Fixed Mobile Convergence a IMS Approach

The paper is aimed at studying and analyzing the network performance parameters of SIP protocol. SIP is content based protocol, in which various message are required to be transacted so that a session could be created, terminated or modified. Therefore, the objective is to analyze various SIP activities and the delay incurred in session start-up under various network conditions. Proper functioning of IMS platform is dependent on optimum performance of several protocols specified in the standard. Nearly all of the protocols used in IMS are standardized by the IETF. Some of the major protocols are SIP, SDP- signaling protocol, DIAMETERimprovised version of RADIUS protocol,COPS- Common Open Policy Service, H.248- descendant of MEGACo, RTP/RTCPReal Time Protocol/Real Time Control Protocol, etc. Out of all these, Session Initiation Protocol (SIP) is the prominent protocol used to create, terminate and modify the sessions initiated by the user. In order to improve the performance parameters, this is the area where most of the research work is centralized. Hence, to study various aspects of SIP protocol with respect to the network performance is of great interest

Evaluating Extensions to IMS Session Setup for Multicast-based Many-to-Many Services

Telecommunication networks are converging towards an all-IP paradigm that integrates a broad set of value-added services. In this context, the IP Multimedia Subsystem (IMS) is being developed by the 3GPP as a key element to achieve the convergence. Additionally, multiparty services are nowadays acquiring an increasing interest from the industry. In this respect, network multicast provides a cost-effective solution to deliver these services to the user. Nevertheless, although network multicast is being considered as an enabler for one-to-many services (e.g. IPTV) in the IMS, the specifications for many-to-many services still follow a unicast approach (e.g. push-to-talk and conference). This paper describes extensions to the session control procedures in the IMS, to support multicast based multi-user services. The idea was first described in a prior work, but this paper presents enhancements to provide a comprehensive solution and to improve the grade of service (GOS) perceived by the users. In addition, the GOS achieved by the proposal is evaluated. First, the bandwidth utilization for the multicast-based multi-user services is analyzed and compared against the unicast scenario. Next, the GOS is evaluated using an analytical approach, by obtaining the mathematical expressions for the session and user plane setup delays. Finally, the GOS is also evaluated using an experimental approach, and the results are compared with values recommended by the ITU-T

Побудова all-IP мереж на базі концепції IMS

Відповідно до мети дослідження, в даній розроблено методологію інноваційних рішень, що дозволяє перейти до мультисервісної мережі зв'язку, побудована математична модель мультисервісної мережі NGN / IMS, яка модернізованоа відповідно до запропонованого підходу, а також розроблено метод оцінки характеристик якості надання послуг у подібній мережі. Оцінено ефективність запропонованого методу.According to the purpose of the study, this article has developed a methodology for innovative solutions that allow switching to a multiservice communication network, built a mathematical model of the NGN / IMS multiservice network, which is upgraded according to the proposed approach, and developed a method for evaluating the quality characteristics of service delivery in such a network. The effectiveness of the proposed method is evaluated

Improving initiation, decision and execution phases for vertical handover in heterogeneous wireless mobile networks

One of the challenging issues in Next Generation Wireless Systems (NGWS) is seamless Vertical Handover (VHO) during the mobility between different types of technologies (3GPP and non-3GPP) such as Global System for Mobile Communication (GSM), Wireless Fidelity (Wi-Fi), Worldwide Interoperability for Microwave Access (WiMAX), Universal Mobile Telecommunications System (UMTS) and Long Term Evolution (LTE). Therefore, the telecommunication operators are required to develop aninteroperability strategy for these different types of existing networks to get the best connection anywhere, anytime without interruption of the ongoing sessions. In order to identify this problem accurately, the research study presented in this thesis provides four surveys about VHO approaches found in the literature. In these surveys, we classify the existing VHO approaches into categories based on the available VHO techniques for which we present their objectives and performances issues. After that, we propose an optimised VHO approach based on the VHO approaches that have been studied in the literature and take into consideration the research problems and conclusions which arearisen in our surveys. The proposed approach demonstrates better performance (packet loss, latency and signaling cost), less VHO connection failure (probability of minimising VHO reject sessions), less complexity and an enhanced VHO compared with that foundin the literature. It consists of a procedure which is implemented by an algorithm. The proposed procedure of loose coupling and Mobile Internet Protocol version 4 (MIPv4) provides early buffering for new data packets to minimise VHO packet loss and latency. Analysis and simulation of the proposed procedure show that the VHO packet loss and latency are significantly reduced compared with previous MIPv6 procedures found in the literature.The proposed algorithm is composed of two main parts: Handover Initiation and Optimum Radio Access Technologies (RATs) list of priority. The first part includes two main types of VHO and gives priority to imperative sessions over alternative sessions. IIIThis part is also responsible for deciding when and where to perform the handover by choosing the best RATs from the multiple ones available. Then, it passes them to the decision phase. This results in reducing the signaling cost and the inevitable degradation in Quality of Service (QoS) as a result of avoiding unnecessary handover processes. The second part defines RATs list of priority to minimise VHO connection failure. Analysis and simulation based performance evaluations then demonstrate that the proposed algorithm outperforms the traditional algorithms in terms of: (a) the probability of VHOconnection failure as a result of using the optimum RATs list of priority and (b) thesignaling cost and the inevitable degradation in QoS as a result of avoiding unnecessary handover processes