Entanglement spread and clean resource inequalities

This article will examine states that superpose different amounts of entanglement and protocols that run in superposition but generate or consume different amounts of entanglement. In both cases we find a uniquely quantum difficulty: entanglement cannot be conditionally discarded without either using communication or causing decoherence. I will first describe the problem of entanglement spread in states and operations, as well as some methods of dealing with it. Then I'll describe three applications to problems that at first glance appear to be quite different: first, a reinterpretation of the old observation that creating n partially entangled states from singlets requires theta(sqrt(n)) communication, but cannot itself be used to communicate; second, a new lower bound technique for communication complexity; third, an explanation of how to extend the quantum reverse Shannon theorem from tensor power sources to general sources.Comment: 11 pages. This is an extended version of an article that appeared in the proceedings of ICMP09: the 16th International Congress on Mathematical Physics. v2. Fixed a sign error in one definitio

Implementation of a new emergency medical communication centre organization in Finland - an evaluation, with performance indicators

<p>Abstract</p> <p>Background</p> <p>There is a great variety in how emergency medical communication centers (EMCC) are organized in different countries and sometimes, even within countries. Organizational changes in the EMCC have often occurred because of outside world changes, limited resources and the need to control costs, but historically there is often a lack of structured evaluation of these organization changes. The aim of this study was to evaluate if the performance in emergency medical dispatching changed in a smaller community outside Helsinki after the emergency medical call centre organization reform in Finland.</p> <p>Methods</p> <p>A retrospective observational study was conducted in the EMCC in southern Finland. The data from the former system, which had municipality-based centers, covered the years 2002-2005 and was collected from several databases. From the new EMCC, data was collected from January 1 to May 31, 2006. Identified performance indicators were used to evaluate and compare the old and new EMCC organizations.</p> <p>Results</p> <p>A total of 67 610 emergency calls were analyzed. Of these, 54 026 were from the municipality-based centers and 13 584 were from the new EMCC. Compared to the old municipality-based centers the new EMCC dispatched the highest priority to 7.4 percent of the calls compared to 3.6 percent in the old system. The high priority cases not detected by dispatchers increased significantly (p < 0.001) in the new EMCC organization, and the identification rate of unexpected deaths in the dispatched ambulance assignments was not significantly (p = 0.270) lower compared to the old municipality-based center data.</p> <p>Conclusion</p> <p>After implementation of a new EMCC organization in Finland the percentage and number of high priority calls increased. There was a trend, but no statistically significant increase in the emergency medical dispatchers' ability to detect patients with life-threatening conditions despite structured education, regular evaluation and standardization of protocols in the new EMCC organization.</p

A Cloud-based RFID Authentication Protocol with Insecure Communication Channels

© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Radio Frequency Identification (RFID) has becomea widespread technology to automatically identify objects and withthe development of cloud computing, cloud-based RFID systemsattract more research these days. Several cloud-based RFIDauthentication protocols have been proposed to address privacyand security properties in the environment where the cloudprovider is untrusted therefore the tag’s data are encrypted andanonymously stored in the cloud database. However, most of thecloud-based RFID authentication protocols assume securecommunication channels between the reader and the cloud server.To protect data transmission between the reader and the cloudserver without any help from a third party, this paper proposes acloud-based RFID authentication protocol with insecurecommunication channels (cloud-RAPIC) between the reader and the cloud server. The cloud-RAPIC protocol preserves tag privacyeven when the tag does not update its identification. The cloudRAPIC protocol has been analyzed using the UPriv model andAVISPA verification tool which have proved that the protocolpreserves tag privacy and protects data secrecy

Mobile Networking

We point out the different performance problems that need to be addressed when considering mobility in IP networks. We also define the reference architecture and present a framework to classify the different solutions for mobility management in IP networks. The performance of the major candidate micro-mobility solutions is evaluated for both real-time (UDP) and data (TCP) traffic through simulation and by means of an analytical model. Using these models we compare the performance of different mobility management schemes for different data and real-time services and the network resources that are needed for it. We point out the problems of TCP in wireless environments and review some proposed enhancements to TCP that aim at improving TCP performance. We make a detailed study of how some of micro-mobility protocols namely Cellular IP, Hawaii and Hierarchical Mobile IP affect the behavior of TCP and their interaction with the MAC layer. We investigate the impact of handoffs on TCP by means of simulation traces that show the evolution of segments and acknowledgments during handoffs.Publicad

Efficient and Low-Cost RFID Authentication Schemes

Security in passive resource-constrained Radio Frequency Identification (RFID) tags is of much interest nowadays. Resistance against illegal tracking, cloning, timing, and replay attacks are necessary for a secure RFID authentication scheme. Reader authentication is also necessary to thwart any illegal attempt to read the tags. With an objective to design a secure and low-cost RFID authentication protocol, Gene Tsudik proposed a timestamp-based protocol using symmetric keys, named YA-TRAP*. Although YA-TRAP* achieves its target security properties, it is susceptible to timing attacks, where the timestamp to be sent by the reader to the tag can be freely selected by an adversary. Moreover, in YA-TRAP*, reader authentication is not provided, and a tag can become inoperative after exceeding its pre-stored threshold timestamp value. In this paper, we propose two mutual RFID authentication protocols that aim to improve YA-TRAP* by preventing timing attack, and by providing reader authentication. Also, a tag is allowed to refresh its pre-stored threshold value in our protocols, so that it does not become inoperative after exceeding the threshold. Our protocols also achieve other security properties like forward security, resistance against cloning, replay, and tracking attacks. Moreover, the computation and communication costs are kept as low as possible for the tags. It is important to keep the communication cost as low as possible when many tags are authenticated in batch-mode. By introducing aggregate function for the reader-to-server communication, the communication cost is reduced. We also discuss different possible applications of our protocols. Our protocols thus capture more security properties and more efficiency than YA-TRAP*. Finally, we show that our protocols can be implemented using the current standard low-cost RFID infrastructures.Comment: 21 pages, Journal of Wireless Mobile Networks, Ubiquitous Computing, and Dependable Applications (JoWUA), Vol 2, No 3, pp. 4-25, 201