Call Control Component implementing converged Telephony- Internet networks

Global telecommunications are in the early stages of a fundamental transformation, in which telecommunication networks and information technologies are yielding converged networks named Next Generation Networks (NGN). In this context this article presents a call control component able to handle calls between a telephone and a PC, accordingly to actions decided by the application layer that sets up and redirects calls between terminals over heterogeneous networks like Internet and PSTN. This goal is achieved through software adapters offering APIs porting standard protocols like Media Gateway Control Protocol and Intelligent Network Application Protocol (INAP), to CORBA-based software components

Unified Messaging Systems: an Evolutionary Overview

Over the last decade, the widespread demand and use of the internet has changed the direction of the telecommunications industry as it was recognised that the internet could be used as an inexpensive way to handle not only data but also voice communications. This convergence of traditional voice and data technologies towards an IP-based open architecture has been paralleled by a convergence of the internet and mobile communications. As a result of these convergences, unified messaging has emerged as a technically viable service. Integrated messaging services that offer partial unification of different message types are already in the marketplace. This paper asks what unified messaging means and examines underlying architectural developments that are likely to shape the unified messaging applications of the future

Security aspects in voice over IP systems

Security has become a major concern with the rapid growth of interest in the internet. This project deals with the security aspects of VoIP systems. Various supporting protocols and technologies are considered to provide solutions to the security problems. This project stresses on the underlying VoIP protocols like Session Initiation Protocol (SIP), Secure Real-time Transport Procotol (SRTP), H.323 and Media Gateway Control Protocol (MGCP). The project further discusses the Network Address Translation (NAT) devices and firewalls that perform NAT. A firewall provides a point of defense between two networks. This project considers issues regarding the firewalls and the problems faced in using firewalls for VoIP; it further discusses the solutions about how firewalls can be used in a more secured way and how they provide security

A survey of VoIP intrusions and intrusion detection systems

ABSTRACT This poper presents R survey of the securiv problems in VoIP networks, with an emphasis on both intrusions and intrusion detection methods. It examines the intrusion issues in diflerent components of VoIP systems, points to the strengths and shortcomings in the existing intrusion detection methods and intrusion detection systems and suggests possible future research directions

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

Analyzing Voice And Video Call Service Performance Over A Local Area Network

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2010Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2010Bu çalışmada, VOIP teknolojisinden ve bu teknolojiyi kablolu ve kablosuz ortamda gerçeklemenin en önemli darboğazları anlatılacaktır. Ayrıca H.323, SIP (Session Initiation Protocol), Megaco ve MGCP gibi yaygın olarak kullanılan ses iletim protokolleri ve H.261, H.263 ve H.264 gibi görüntü iletim protokollerinden bahsedilmiştir. Ses kodek seçimi ve VOIP servis kalitesine etki eden faktörleri anlatılmaktadır. Bu tezde, ses, görüntü ve veri iletişimini aynı anda bünyesinde barındıran gerçek şebekeler simüle edilecektir. Kullanıcılara rastlantısal olarak ses, görüntü ve FTP gibi birtakım uygulamalar atanmıştır. Ayrıca önerilen kablolu şebekeye, kablosuz bir şebeke ilave edilerek sonuçlar incelenecektir. Optimal servis kalitesini sağlamak için seçilen uygun kuyruklama mekanizmaları ve kodek seçimlerini içeren senaryolar incelenecek ve OPNET ile elde edilmiş simülasyon sonuçları tartışılacaktır.In this study, we present a detailed description of the VoIP and also the most common challenges of implementing voice communication into wireline or wireless networks are discussed. Common voice protocols, such as H.323, Session Initiation Protocol (SIP), Megaco, MGCP and video protocols such as H.261, H.263, H.264 are described as well. CODEC selection and factors affecting VoIP Quality of Service are analyzed. We simulate a real network which includes both voice, video and data communication simultaneously. Workstations are randomly assigned to different applications, such as voice, video and FTP. We will also implement a wireless network to our proposed system. The scenarios including selecting appropriate queuing scheme and codec selection are presented and the simulation results with OPNET are drawn.Yüksek LisansM.Sc

An architecture for the integration of Wireless Actuation Capabilities with IP Multimedia Subsystem

The IP Multimedia Subsystem (IMS) is an architecture that aims at seamlessly delivering multimedia services. It enables IP multimedia services for end-user using standard Internet based protocols such as Session Initiation Protocol (SIP). Examples of multimedia services include presence, instant messaging, enhanced voice and video, pervasive gaming and emergency services. Wireless actuators are small scale devices that can receive/accept instructions and act on their surrounding environment. They are broadly used in automation industry and intelligent control systems. With the rapid development of Internet and mobile telecommunication technologies, more and more actuators are being deployed in applications such as environment monitoring, home automation and health care to improve human beings’ living conditions. Combining actuators’ actuation capabilities with IMS will certainly enable novel value added services. However, the actuator networks are application specific and provide proprietary interfaces to the external world. Integrating wireless Actuator Networks (AN) with IMS to enable actuation service to IMS end users through standard protocols and interfaces is the objective of this thesis. There are several challenges related to this integration: First, there is no ready-to-use architecture for the integration. New functional entities and suitable protocols for actuation triggering are needed. Second, there are no actuators in the market with open interfaces to the external world, we need to find alternative solutions for the realization of the integrated architecture. Third, there is no information model for abstracting actuation command semantics and this has to be defined. In this thesis we derive a set of requirements for the integration of AN actuation capabilities with IMS, we review and evaluate related work, and then propose a novel architecture. This architecture includes two new functional entities for IMS: The Actuation Control Function (ACF) and the Wireless Actuator Gateway (WAG). The ACF handles high level actuation requests from other applications. It acts as an intermediate component and hides the low level actuation commands from the applications. The WAG transforms high level actuation commands to low level, proprietary and actual actuation commands that can be understood and executed by actuators. A detailed survey and evaluation of existing protocols for actuation command carrying is also provided. We define an actuation command information model to abstract the actuation triggering instructions. We implement the key components of the proposed architecture. A proof of concept prototype has been implemented using simulated robots equipped with actuators. The average end-to-end actuation delay of our architecture is evaluated through experiments with the prototype

Desenvolvimento de sistemas media gateway de acesso ETSI TISPAN

Mestrado em Engenharia Electrónica e de Telecomunicações e InformáticaAs Redes de Próxima Geração prometem trazer muitos benefícios aos operadores de telecomunicações. Os operadores que as implementarem poderão oferecer uma maior variedade de aplicações e serviços aos seus subscritores independentemente da sua localização, com custos e complexidade reduzidos. Desta forma os operadores poderão aumentar a sua oferta, com os novos serviços que podem ser oferecidos, enquanto as suas despesas de capital e operação poderão ser reduzidas com a migração das redes telef ónicas baseadas em TDM para as novas arquitecturas de convergência IP. A presente dissertação efectua um estudo destas redes, apresentando os seus requisitos, arquitecturas, protocolos e princípios de funcionamento, dando especial relevância ao sistemas Media Gateway de Acesso e de Trunking. Desta forma foram estudadas e testadas soluções dos subsistema TISPAN de emulação da rede PSTN baseada em IMS para os acessos fixos e dos sistemas de Trunking TISPAN e IMS. É também apresentado o projecto de desenvolvimento de uma Media Gateway de Acesso a integrar na rede SHipNET da PT Inovação. ABSTRACT: Next Generation Networks will bring many benefits to telecommunication networks operators. Operators that deploy it can potentially offer a much wider range of applications and services, to subscribers irrespective of their location, at reduced cost and complexity. This way, operators will increase their revenues through the additional services that can be offered, while their capital expenditure and operation expenses will decrease with their migration from legacy TDM networks to converged network architectures based on IP. This thesis presents a study of these networks, showing their requirements, architectures, protocols and operational principles, giving special relevance to the Media Gateway systems: Access and Trunking. Thus, were studied and tested solutions of the TISPAN PSTN Emulation Subsystem based on IMS, for fixed access, and Trunking systems of IMS and TISPAN. This thesis also presents the project of development of an Access Media Gateway to integrate into the SHipNET network of PT Inovação

The generic context sharing protocol GCSP : Application to signaling in a cross-network and multi-provider environment

This paper proposes a new signaling paradigm and a new signaling protocol called the Generic Context Sharing Protocol (GCSP) for the construction of a global control plane over present and future communication networks. After identifying the special nature of the control plane software involved in the setup of a conversational service instance it examines the various mechanisms for information sharing which leads to our new proposal. We show that this new data-based protocol is better suited to control plane requirements than the present day’s command-oriented signaling mechanisms. We indicate the basic principles of the protocol and we give a brief description of the generic context. We show the place of this proposal in the present day research efforts and we mention a practical implementation case.8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI