Secure Enablement of Real Time Applications: A Novel End-to-End Approach

The Internet has evolved into a multi-service Internet Protocol (IP) network with support for various types of traffic, including multimedia. Given the relatively open nature of IP networks, securely enabling multimedia services is increasingly important. While protocols such as Secure Real Time Protocol (SRTP) provide container formats for various applications, the supporting security solutions lack end-to-end secure key management. In this paper, we propose a novel secure key management framework targeted for real time applications in multi-operator environments. In particular, by leveraging an Identity-Based Authenticated Key Exchange (IBAKE) protocol, we develop secure key management solutions to support two-party communications, conferencing applications, call forking, call redirect, and deferred delivery. Our framework eliminates the need for costly public key infrastructure (PKI) or other online solutions, overcomes the problem of key escrow while providing perfect forward and backwards secrecy, and works across applications and media types. Overall, our solution opens-up new lines of research and business opportunities in secure application enablement. (c) 2012 Alcatel-Lucent

Postoperative atrial fibrillation:mechanisms, manifestations and management

Postoperative atrial fibrillation (POAF) complicates 20-40% of cardiac surgical procedures and 10-20% of non-cardiac thoracic operations. Typical features include onset at 2-4 days postoperatively, episodes that are often fleeting and a self-limited time course. Associated adverse consequences of POAF include haemodynamic instability, increased risk of stroke, lengthened hospital and intensive care unit stays and greater costs. Underlying mechanisms are incompletely defined but include intraoperative and postoperative phenomena, such as inflammation, sympathetic activation and cardiac ischaemia, that combine to trigger atrial fibrillation, often in the presence of pre-existing factors, making the atria vulnerable to atrial fibrillation induction and maintenance. A better understanding of the underlying mechanisms might enable the identification of new therapeutic targets. POAF can be prevented by targeting autonomic alterations and inflammation. beta-Blocker prophylaxis is the best-established preventive therapy and should be started or continued before cardiac surgery, unless contraindicated. When POAF occurs, rate control usually suffices, and routine rhythm control is unnecessary; rhythm control should be reserved for patients who develop haemodynamic instability or show other indications that rate control alone will be insufficient. In this Review, we summarize the epidemiological and clinical features of POAF, the available pathophysiological evidence from clinical and experimental investigations, the results of prophylactic and therapeutic approaches and the consensus recommendations of various national and international societies