QOS ANALYSIS OF WIRELESS LINK ACCESS FOR TRIPLE PLAY SERVICES ON IMS NETWORK

Nowadays, many operators of cellular networks that try to reduced VoIP traffic over their network since it destroys their revenue. But, a deployed IMS network will put operators into a position where they have a secured and chargeable environment at hand. Since the IMS acts as overlay architecture for IP access networks, any communication media that supports IP data transfers on top of it would be a candidate for transporting the signaling and the media flows. IMS is the concept of an Internet Protocol (IP) that enables a variety of services voice, data, and video are connected in the same network and can can combine PSTN, celullar and internet technology within single platform based on SIP. In this thesis, evaluation of QoS performance and analysis is interesting to see how well they are suited to transport IMS services and considered current mobile access network technologies like EDGE ,HSDPA and its extension LTE 4G. To ensure the triple play services delivery meets the better expectations of end users, factors affecting QoS on SIP Registration, SIP Invite and Call Session must be properly considered. This thesis will give a study of a the IMS Session especially on QoS’ metric which will serve us to accomplish the QoS measurement within various access network in the case of Triple Play sessions (video call, voice call, and instant message) carried over : EDGE , Wireless LAN 802.11g,HSDPA and LTE 4G. The test results stated that the entire access network has QoS performance on control plane and user plane that can be accommodated by the ITU-T standards. Wifi, LTE and HSDPA have excellent quality in IMS networks, while EDGE has the lowest performance and almost equivalent to other network access to its instant messaging service. The result shows that the value of a call setup delay for Wifi 0.009822531 ms or 0.73 times lower then the CSD LTE aggregate. CSD HSDPA aggregate value is 0.018337193 ms or 1:38 times higher Compared to CSD LTE. The highest value for the CSD is EDGE with 0.043958333 ms or 3.3 times higher than the CSD LTE. Keywords: QoS, SIP, IMS, Call Setup Delay, EDGE, Wireless LAN, HSDPA, LTE 4G

A study of mobile VoIP performance in wireless broadband networks

Voice service is to date still the killer mobile service and the main source for operator revenue for years to come. Additionally, voice service will evolve from circuit switched technologies towards packet based Voice over IP (VoIP). However, using VoIP over wireless networks different from 3GPP cellular technologies makes it also a disruptive technology in the traditional telecommunication sector. The focus of this dissertation is on determining mobile VoIP performance in different wireless broadband systems with current state of the art networks, as well as the potential disruption to cellular operators when mobile VoIP is deployed over different access networks. The research method is based on an empirical model. The model and experiments are well documented and based on industry standards for voice quality evaluation. The evaluation provides results from both experiments in a controlled laboratory setup as well as from live scenarios. The research scope is first, evaluate each network technology independently; second, investigate vertical handover mobility cases; third, determine other aspects directly affecting end user experience (e.g., call setup delay and battery lifetime). The main contribution of this work is a systematic examination of mobile VoIP performance and end user experience. The research results point out the main challenges for achieving call toll quality, and how derive the required changes and technological performance roadmap for improved VoIP service. That is, investigate how the performance and usability of mobile VoIP can eventually be improved to be a suitable substitute for circuit switched voice. In addition, we evaluate the potential disruption to cellular operators that mobile VoIP brings when deployed over other access networks. This research extends the available knowledge from simulations and provides an insight into actual end user experience, as well as the challenges of using embedded clients in handheld devices. In addition, we find several issues that are not visible or accounted for in simulations in regard to network parameters, required retransmissions and decreased battery lifetime. The conclusion is that although the network performance of several wireless networks is good enough for near toll quality voice in static scenarios, there are still a number of problems which make it currently unfeasible to use as a primary voice service. Moreover, under mobility scenarios performance is degraded. Finally, there are other issues apart from network performance such as energy consumption, hardware limitations and lack of supporting business models (e.g., for WiFi mesh) that further limit the possibility of rolling out mobile VoIP services

Kerberos: A real-time fraud detection system for IMS-enabled VoIP networks

In this paper we present the design, implementation and experimental evaluation of Kerberos, an architecture for the detection of frauds in current generation Voice over IP (VoIP) networks. Kerberos is fed by an On-line Charging System (OCS) generating events associated with the setup, evolution and tear-down of end-user calls in a VoIP network compliant with the IP Multimedia Subsystem (IMS) specification. Such events are properly correlated in order to identify, in real-time, patterns associated with a fraudulent utilization of the Operator's resources. The detection phase can in turn trigger the subsequent remediation actions. Communication between the OCS and Kerberos is based on an asynchronous paradigm, whereas event correlation and analysis are effectively realized through a Complex Event Processing approach. The paper will shed light on both the design and the implementation of the system, whose performance is then evaluated by relying on a real-world dataset of Call Detail Record (CDR) events provided by Tiscali, a well known Italian Operator

EVEREST IST - 2002 - 00185 : D23 : final report

Deliverable públic del projecte europeu EVERESTThis deliverable constitutes the final report of the project IST-2002-001858 EVEREST. After its successful completion, the project presents this document that firstly summarizes the context, goal and the approach objective of the project. Then it presents a concise summary of the major goals and results, as well as highlights the most valuable lessons derived form the project work. A list of deliverables and publications is included in the annex.Postprint (published version