Chowdhury Sharif Hasan

ePet: when cellular phone learns to recognize its owner

In this paper an adaptive solution to secure the authentication process of cellular phones has been proposed. Gait and location tracks of the owner are used as the metrics for authentication. The cellular phone is envisioned to become as adaptive as a pet animal of the owner. The cellular phone learns various intrinsic attributes of the owner like his voice, face, hand and fingerprint geometry and interesting patterns in the owners daily life and remembers those to continually check against any anomalous behavior that may occur due to the stealing of the phone. The checking is done level wise. Higher level of authentication is more stringent. Only when the cellular phone recognizes significant anomaly in a lower level, it goes one level up in the security hierarchy. The iPhones accelerometer and A-GPS module have been utilized to record gait and location signatures. A fast and memory efficient variation of Dynamic Time Warping (DTW) algorithm called FastDTW has been used to compute the similarity score between gait samples.

A Privacy Enhancing Approach for Identity Inference Protection in Location-Based Services

Recent advances in mobile handheld devices have facilitated the ubiquitous availability of location based services. Systems which provide location based services have always been vulnerable to numerous privacy threats. The more we aim at safe usage of location based services, the more we feel the necessity of a secure location privacy system. Most of the existing systems adopt the mechanism of satisfying k-anonymity which means that the exact user remains indistinguishable among k-1 other users. These systems usually propose the usage of a location anonymizer (LA) to achieve k-anonymity. In this paper we show that satisfying k-anonymity is not enough in preserving location privacy violation. Especially in an environment where a group of colluded service providers collaborate with each other, a user’s privacy can be compromised. We present a detailed analysis of such attack on privacy and propose a novel and powerful privacy definition called s-proximity. In addition to building a formal definition for s-proximity, we show that it is practical and it can be incorporated efficiently into existing systems to make them secure.

ELALPS: A Framework to Eliminate Location Anonymizer from Location Privacy Systems

Countless challenges to preserving a user’s location privacy exist and have become more important than ever before with the proliferation of handheld devices and the pervasive use of Location-based Services. It is not possible to access Location-based services and, at the same time, to preserve privacy when the user provides his exact location information. To achieve privacy, most third party based systems use a location anonymizer to achieve k-anonymity so that the user remains indistinguishable among k-1 other requesters. In this paper, we present a novel approach called ELALPS to preserve location privacy without any intermediate location anonymizer. Our framework uses a new concept, namely, Landmark Influence Space (LIS) that proves to be efficient in location anonymization and query processing. The framework is complemented by a collaboration-based light-weight k-anonymity protocol that does not require standard cryptographic operations and trust formation among users. Evaluation shows that our system has been able to bridge the gap between privacy and performance.

Design and implementation of S-MARKS: A secure middleware for pervasive computing applications

As portable devices have become a part of our everyday life, more people are unknowingly participating in a pervasive computing environment. People engage with not a single device for a specific purpose but many devices interacting with each other in the course of ordinary activity. With such prevalence of pervasive technology, the interaction between portable devices needs to be continuous and imperceptible to device users. Pervasive computing requires a small, scalable and robust network which relies heavily on the middleware to resolve communication and security issues. In this paper, we present the design and implementation of S-MARKS which incorporates device validation, resource discovery and a privacy module.

Towards developing a trust-based security solution

Wireless sensor network has emerged as a new information and data gathering paradigm based on the collaborative efforts of a large number of autonomous sensing devices. With small memories and processors, limited energy and tiny packets, sensor networks cannot afford traditional luxury security solutions; this limitation causes security threats. There are several important security challenges, including access control, message integrity and confidentiality, and trust solutions that require us to use a careful design of resource constraints for pursuing more enhanced security solutions for a wireless sensor network. In this paper, we present a new idea of persistent security solutions that support trust for general purpose Wireless Sensor Networks.

An Approach for Ensuring Robust Safeguard against Location Privacy Violation

The challenge of preserving user’s location privacy is more important now than ever before with the proliferation of handheld devices and the pervasive use of location based services. To protect location privacy, we must ensure k-anonymity so that the user remains indistinguishable among k-1 other users. There is no better way but to use a location anonymizer (LA) to achieve k-anonymity. However, its knowledge of each user’s current location makes it susceptible to be a single-point-of-failure. In this paper, we propose a formal location privacy framework, termed SafeGrid that can work with or without an LA. In SafeGrid, LA is designed in such a way that it is no longer a single point of failure. In addition, it is resistant to known attacks and most significantly, the cloaking algorithm it employs meets reciprocity condition. Simulation results exhibit its better performance in query processing and cloaking region calculation compared with existing solutions. As an added feature, in SafeGrid a user has the option of not using LA, yet achieving as much obfuscation (deliberate degradation of location data) as needed without ever sacrificing performance gain.

PryGuard: a secure distributed authentication protocol for pervasive computing environment

Handheld devices have become so commonplace nowadays that they are an integral part of our everyday life. Proliferation of these mobile handheld devices equipped with wide range of capabilities has bolstered widespread popularity of pervasive computing applications. In such applications many devices interact with each other by forming ad hoc wireless networks. The necessity of such unavoidable inter-device dependency along with volatile nature of connectivity and the lack of a fixed infrastructure for authentication and authorization, devices are susceptible and vulnerable to malicious active and passive snoopers. If a device registers a malicious device as its valid neighbor, the security and privacy of entire system might be jeopardized. Such sensitivity to malevolent activity necessitates the need for a robust mechanism to maintain a list of valid devices that will help to prevent malicious devices from authenticating successfully. In this paper, we present the feasibility of using a decentralized protocol in order to prevent malicious devices from participating illicitly into the ad hoc networks.

Home-Healthcare-Network (h2n): an autonomous care-giving system for elderly people

As the worlds population ages, the number of elderly people suffering from various diseases increases. Due to a variety of reasons such as convenience or a need for security and privacy these elderly people generally prefer to avail healthcare facilities at their home. Advances in ubiquitous computing and wireless sensor networking have opened up new opportunities in healthcare systems. In-home pervasive networks may assist residents by providing memory enhancement, remote control of home appliances, medical data lookup and emergency communication. This is time to break through the physical boundaries of hospitals and bring healthcare facilities to the homes. Wireless and internet-based healthcare devices can play a vital role in this regard given that reliable, individualized systems with user-friendly interfaces are developed to enable elderly people feel comfortable with making use of novel technology. This paper presents Home Healthcare Network (H2N), a complete system integrating the abundance of existing sensor nodes and other devices with pervasive, wireless networks. Our approach focuses on improving social aspects of elderly care besides the conventional care-giving functionalities. Finally, we talk about the importance of preserving privacy of such a system and propose a primitive solution for the inclusion of privacy awareness in the system. Although H2N is basically designed to function as a healthcare aide for the elderly people, with little customization it can be used to accommodate other user groups as well.