This article deals with quality of service (QoS) in internet protocol (IP) telephony by applying software-defined networking (SDN) tools. The authors develop a new design that deterministically classifies real-time (RTP) streams based on data found session initiation (SIP) using SIP proxy as mediator, and the concept making this possible is called SDN. Compared to traditional networks, SDN allo...

This paper discusses the problem of interoperability of IP Telephony and Switched Circuit Networks in the area of routing information. We describe and analyze a solution for directory-based routing. We will present an architecture based on a distributed database on the switched circuit network and the IP network. The aim of the solution is to provide efficient service management, close to optim...

The article considers the features of organizing highly efficient telephone communication using cloud-based PBXs.
 advantages solutions based on IP-telephony compared to classical automatic exchanges are treated. It is shown that use a virtual PBX as separate configuration dedicated server will provide flexible system settings.
 virtualization model considered. analysis methods carrie...

We describe our Session Initiation Protocol (SIP)-based VoiceXML browser, sipvxml, that allows programming interactive voice response applications that are accessible from telephones as well as IP phones. We also describe how we have used sipvxml in our multi-party multimedia conferencing server. We propose other applications and extensions that can benefit from this technology in our IP teleph...

The voice quality in Internet Protocol (IP) telephony is significantly influenced by various factors, including delay, delay variation, bandwidth congestion and the distribution of packet loss. Hence, the performance of IP telephony systems is highly dependent on understanding the contribution of these factors to the voice quality. This paper deals about a method for classifying Voice over IP (...

This paper describes the author’s perspective on multimedia quality prediction methodologies for advanced mobile and IP-based telephony, and reports related experiments and trials. First the paper describes the need for perceptual QoS assessment in which various quality factors in advanced mobile and IP-based telephony are analyzed. Then an objective quality prediction scheme is proposed from t...

Packet loss is an important parameter for dimensioning network links or traffic classes carrying IP telephony traffic. We present a model based on the Markov modulated Poisson process (MMPP) which calculates packet loss probabilities for a set of superpositioned voice input sources and the specified link properties. We do not introduce another new model to the community, rather try and verify o...

IP telephony has long been one of the most widely used applications of the peer-to-peer paradigm. Hardware phones with built-in peer-to-peer stacks are used to enable IP telephony in closed networks at large company sites, while the wide adoption of smart phones provides the infrastructure for software applications enabling ubiquitous Internet-scale IP-telephony. Decentralized peer-to-peer syst...