Henry N. Jerez

Efficient User Controlled Inter-Domain SIP Mobility Authentication, Registration, and Call Routing

Over the past decade, multimedia services have gained significant acceptance and played an important role in the convergence of IP networks. The proliferation of mobile devices and the nomadic user and computing lifestyles on current networks make mobility support a crucial ingredient of current IP-based multimedia systems. The Session Initiation Protocol (SIP) presents one approach towards supporting IP mobility. Additionally, SIP is increasingly gaining in popularity as the next generation multimedia signaling and session establishment protocol, and the SIP infrastructure is anticipated to be extensively deployed all over the Internet. We have lately proposed an approach to inter-domain SIP mobility which we call H-SIP. H-SIP is a user-controlled mobility scheme that improves personal and terminal mobility. H-SIP uses persistent identifiers and leverages the traditional SIP architecture to abstract any domain binding from users. This paper expands on our previous work and experimentally proves the efficiency of H-SIP in achieving inter-domain authentication and call routing through modeling and real-time measurements.

H-SIP Inter-Domain SIP Mobility: Design

Supporting mobility in IP networks is a crucial step towards satisfying the nomadic communication paradigms on the current Internet. The Session Initiation Protocol (SIP) presents one approach towards supporting IP mobility and is increasingly gaining in popularity as the next generation multimedia signaling and session establishment protocol. In this paper, we explore the design of an efficient approach to inter-domain SIP mobility in an attempt to improve personal and terminal mobility schemes. We apply a persistent identification framework to application level SIP addressing by introducing a level of indirection on top of the traditional SIP architecture. We show how this approach helps achieve efficient inter-domain authentication and call routing towards providing inter-domain mobility. This paper presents the design of H-SIP, while its implementation is described in a companion paper.

Networked Control Systems: Algorithms and Experiments

In this chapter we address the problem of implementing control systems using general purpose communication networks to transmit plant state information and control signals. The main idea is to expose the issues that have to be considered when implementing teleoperation and telepresence applications exploiting already deployed communication infrastructure. Some of these applications may be implemented with local controllers and remote supervisory systems, where the remote client sends set points according to the process status received, but the control loops are closed locally. Other applications however, might require gathering information from different and geographically distant agents or sensors. In such a case, loops cannot be closed locally, and the state and control signals must travel across the networks. A general purpose communication network will however introduce issues such as propagation time-delays and loss of information. Therefore, the control algorithms must now account for these issues, and they should be robust enough to guarantee a certain level of performance. We develop in this section a series of experiments to identify the issues induced by a general purpose communication network, with specific emphasis on wireless networks. We use standard operating systems and industrial hardware for data acquisition. Then, we propose compensation alternatives to cope with these issues.

Wireless camera and site survey issues over an IEEE 802.11b based wireless network test bed

Wireless LAN systems based on IEEE 802.11 have been a proved and sought after technological innovation, over the past few years. In this paper, we discuss some of the technical aspects for testing and deploying a wireless LAN system at the University of New Mexico, Albuquerque, New Mexico. This shall serve as a model test bed for future research and development, under the aegis of Ibero American Science and Technology Education Consortium (ISTEC).

Real-time streaming over an IEEE 802.11b based wireless LAN test bed

Wireless LAN systems based on IEEE 802.11 (see http://grouper.ieee.org/groups/802/11) have become a path-breaking innovation and have revolutionized the home, educational and office network markets (Kapp, S., IEEE Internet Computing, vol.6, no.1, p.82-5, 2002). We attempt to analyze real-time video streaming issues over a wireless LAN test bed based on such a mature technology. The creation of this test bed is an ongoing effort at the Electrical Engineering & Computer Engineering (EECE) Department at the University of New Mexico, Albuquerque, New Mexico, serving to promote future research and development, under the aegis of Ibero American Science and Technology Education Consortium (ISTEC) (see http://www.istec.org).