ABSTRACT This paper presents a new hidden data insertion procedure based on the estimated probability of the remaining time of the call for the steganographic method called lost audio packets (LACK) steganography. LACK provides hidden communication for real‐time services such as voice over IP. The analytical results presented in this paper concern the influence of LACK's hidden data insertion procedures on the quality of voice transmission and the resistance to steganalysis. The proposed hidden data insertion procedure is also compared with previous steganogram insertion approaches on the basis of estimating the remaining average call duration. Copyright © 2011 John Wiley & Sons, Ltd.

Presents an overview of problems involved in introducing ISDN and new services in the public network of Poland. The technical aspects of the assumed network and services development strategy are considered. The focus is on development alternatives and the process of establishing national requirements for the development.>

The Warsaw metropolitan network is undergoing a radical architectural and technological transformation. The transformation, forced by the large unrealized demand for telephone stations, and structural traffic bottlenecks, is based on the installation of eight digital transit switches of high capacity. The so-formed upper transit layer gives an opportunity for the deployment of an efficient traffic routing system, for carrying the growing traffic well beyond the year 2000 without additional investments. A step-wise strategy is presented far the deployment of a modern traffic routing system in the Warsaw network, adapted to, and taking advantage of the fast transformation of the network. The choice of the strategy is based on a case study of the traffic handling efficiency of various routing systems in a model of the Warsaw metropolitan network.>