Keying

About: Keying is a research topic. Over the lifetime, 6598 publications have been published within this topic receiving 82943 citations.

A cryptographic key sharing method

Abstract: A system for sharing secure keying information with a new device not of a secure wireless network. The keying information may be used for encryption and provided to the new device in a manner which is not susceptible to exposure outside of the secure network. The keying information shared with the new device may be regarded as a birth key. Upon appropriate provision of the birth key, the new device may request with a birth key encrypted message via a communication mode exposed to potential adversaries to be added to the secure network.

Automatic transfer and identification of monitored data with hierarchical key management infrastructure

Abstract: A measurement device (14) includes a measuring unit (42) for obtaining health related parameters of a patient (12), and a body-coupled communication unit (40) for sending at least measurement results. An identification device (20), associated with the patient, includes a body-coupled communication unit (26) for receiving and sending out the measurement results. A gateway device (72) includes a body-coupled communication unit (78) for receiving patient's measurement results. Additionally, a hierarchical relational deployment model (100) facilitates grouping wireless devices in a healthcare environment into subgroups based on relationships between the devices, and a hierarchical key pre-distribution scheme (110) permits distribution of unique keying material for security domains of respective groups of devices, prior to deploying the devices in a healthcare network. Devices can then execute a handshake protocol by which they identify their deepest common node in the deployment model (100), and employ keying material assigned to that nodes group in the pre-distribution scheme (110) to facilitate granular communication security.

Performance of diversity schemes for OFDM systems with frequency offset, phase noise, and channel estimation errors

Abstract: We provide expressions for the bit error rate of various transmit and receive diversity schemes for orthogonal frequency division multiplexing (OFDM) systems in the presence of frequency offset, phase noise, and channel estimation errors. The derivations are also applicable for a general multiplicative distortion of the received signal. Our results show that with perfect channel estimates, practical values of the phase noise do not significantly degrade the performance of the various diversity methods for binary phase-shift keying modulation. In contrast, the transmit diversity schemes for OFDM are much more sensitive to channel estimation errors than maximal ratio combining receive diversity.

Coding of subregions for content-based scalable video

Abstract: We propose a scheme for coding subregions in video scenes to provide content-based scalable video. For each region, a special color is used to represent the nonobject area, and the resulting frames are coded using conventional video coding algorithms. At the decoder, the region shape is recovered based on chroma keying, and hence, content-based manipulations are made possible. A number of techniques that eliminate boundary artifacts common to region-based coding are presented. In this scheme, no explicit shape coding is needed, and advantages of existing coding algorithms are retained. This scheme was submitted to ISO MPEG-4 and performed very well in the subjective tests.