Location-based services (LBS) have become an important part of people’s daily life. However, while providing great convenience for mobile users, LBS result in a serious problem on personal privacy, i.e., location privacy and query privacy. However, existing privacy methods for LBS generally take into consideration only location privacy or query privacy, without considering the problem of protecting both of them simultaneously. In this paper, we propose to construct a group of dummy query sequences, to cover up the query locations and query attributes of mobile users and thus protect users’ privacy in LBS. First, we present a client-based framework for user privacy protection in LBS, which requires not only no change to the existing LBS algorithm on the server-side, but also no compromise to the accuracy of a LBS query. Second, based on the framework, we introduce a privacy model to formulate the constraints that ideal dummy query sequences should satisfy: (1) the similarity of feature distribution, which measures the effectiveness of the dummy query sequences to hide a true user query sequence; and (2) the exposure degree of user privacy, which measures the effectiveness of the dummy query sequences to cover up the location privacy and query privacy of a mobile user. Finally, we present an implementation algorithm to well meet the privacy model. Besides, both theoretical analysis and experimental evaluation demonstrate the effectiveness of our proposed approach, which show that the location privacy and attribute privacy behind LBS queries can be effectively protected by the dummy queries generated by our approach.

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Constructing dummy query sequences to protect location privacy and query privacy in location-based services

Authentication and revocation of users in Vehicular Adhoc Networks (VANETS) are two vital security aspects It is extremely important to perform these actions promptly and efficiently The past works addressing these issues lack in mitigating the reliance on the centralized trusted authority and therefore do not provide distributed and decentralized security This paper proposes a blockchain based authentication and revocation framework for vehicular networks, which not only reduces the computation and communication overhead by mitigating dependency on a trusted authority for identity verification, but also speedily updates the status of revocated vehicles in the shared blockchain ledger In the proposed framework, vehicles obtain their Pseudo IDs from the Certificate Authority (CA), which are stored along with their certificate in the immutable authentication blockchain and the pointer corresponding to the entry in blockchain, enables the Road Side Units (RSUs) to verify the identity of a vehicle on road The efficiency and performance of the framework has been validated using the Omnet++ simulation environment

/pdf/blockchain-based-secured-identity-authentication-and-2nj255qf6a.pdf

Blockchain Based Secured Identity Authentication and Expeditious Revocation Framework for Vehicular Networks

Text retrieval enables people to efficiently obtain the desired data from massive text data, so has become one of the most popular services in information retrieval community. However, while providing great convenience for users, text retrieval results in a serious issue on user privacy. In this paper, we propose a dummy-based approach for text retrieval privacy protection. Its basic idea is to use well-designed dummy queries to cover up user queries and thus protect user privacy. First, we present a client-based system framework for the protection of user privacy, which requires no change to the existing algorithm of text retrieval, and no compromise to the accuracy of text retrieval. Second, we define a user privacy model to formulate the requirements that ideal dummy queries should meet, i.e., (1) having highly similar feature distributions with user queries, and (2) effectively reducing the significance of user query topics. Third, by means of the knowledge derived from Wikipedia, we present an implementation algorithm to construct a group of ideal dummy queries that can well meet the privacy model. Finally, we demonstrate the effectiveness of our approach by theoretical analysis and experimental evaluation. The results show that by constructing dummy queries that have similar feature distributions but unrelated topics with user queries, the privacy behind users’ textual queries can be effectively protected, under the precondition of not compromising the accuracy and usability of text retrieval.

A dummy-based user privacy protection approach for text information retrieval

Location-based services (LBSs) provide enhanced functionality and convenience of ubiquitous computing, but they open up new vulnerabilities that can be utilized to violate the users’ privacy. The leakage of private location data in the LBS context has drawn significant attention from academics and industry due to its importance, leading to numerous research efforts aiming to confront the related challenges. However, to the best of our knowledge, none of relevant studies have performed a qualitative and quantitative comparison and analysis of the complex topic of designing countermeasures and discussed the viability of their use with different kinds of services and the potential elements that could be deployed to meet new challenges. Accordingly, the purpose of this survey is to examine the privacy-preserving techniques in LBSs. We categorize and provide an inside-out review of the existing techniques. Performing a retrospective analysis of several typical studies in each category, we summarize their basic principles and recent advances. Additionally, we highlight the use of privacy-preserving techniques in LBSs for enabling new research opportunities. Providing an up-to-date and comprehensive overview of existing studies, this survey may further stimulate new research efforts into this promising field.

Location Privacy-preserving Mechanisms in Location-based Services: A Comprehensive Survey

Summary
In road network, vehicles' location may be identified, and their transmissions may even tracked by eavesdrops (eg, safety messages) that contain sensitive personal information such as identity and location of the vehicle. This type of communication leads to breaking the users' trajectory privacy. Frequently changing pseudonyms are widely accepted as a solution that protects the trajectory privacy of users in road networks. However, this solution may become invalid if a vehicle changes its pseudonym at an improper occasion. To cope with this issue, we presented an efficient pseudonym change strategy with multiple mix zones scheme to provide trajectory privacy for road network. In addition, we protected vehicles against linkability attack by cheating mechanism. Henceforth, we constructed a cheating detection mechanism which allows the vehicles to verify whether the pseudonym change process is successful or not and also detect to malicious vehicles. In this way, users' trajectory privacy can be improved. Finally, by taking the anonymity set size (ASS) as the trajectory privacy metric, we exhibit by means of simulations that the proposed scheme is effective in multiple networks scenarios.

Pseudonym changing strategy with multiple mix zones for trajectory privacy protection in road networks

Road traffic information has become indispensable for routine vehicular communication but user location privacy an important issue which did not well addressed. An adversary may attack a user by tracking location in routine vehicular communication. Although, continuously changing pseudonyms is a promising solution to attain location privacy in road networks, it has been observed that changing pseudonym at improper time or location may again become a threat for location preservation. As a result, a number of techniques for pseudonym-change have been proposed to achieve location privacy on road networks but most of location based services depend upon speed, GPS position and direction angle services. Hence, sensitive information is periodically broadcasted in every 100-300 ms providing an opportunity to adversaries for accessing critical information and easily tracking vehicles. Moreover, existing methods such as RPCLP, EPCS and MODP for attaining location privacy in mix-zones environment have severely suffered due to large number of pseudonym-changes. To cope with these issues, we presented a Dynamic Pseudonym based Multiple Mix-zones (DPMM) strategy to acquire the highest level of accuracy and privacy. The concept of executing dynamic pseudonym change has been forwarded with respect to pseudonyms, velocity and direction of moving objects. We performed our simulations by using one SUMO simulator and analyzed results compared with existing pseudonym-changing techniques. Our simulation results outperformed various existing techniques and provided better results for achieving high privacy rate, requiring small number of pseudonym-change as well as providing best performance.

DPMM: dynamic pseudonym-based multiple mix-zones generation for mobile traveler

The selection of modulation schemes is an essential stage for every communication network. In optical wireless communication, the analysis of modulation schemes is needed to improve the transmitters and receivers to reinforce the received signal energy. In this work, comparative investigation of key attributes of various modulation schemes used in optical communication systems. Conventional schemes, including on off keying and pulse position modulation, are used as reference to analyze the advanced modulation schemes such as digital pulse interval modulation (DPIM)/dual header pulse interval modulation (DH-PIM) in terms of some benchmark parameters such as transmission power, bandwidth requirement, capacity of system, symbol length, packet correction rate and frequency of transmissions and retransmissions. DH-PIM shows the potential benefit of reduced transmission power, minimum bandwidth and shortest possible symbol length while DPIM offers quick transmission rates with least error rates. The overall complexity involved in modulation schemes is also found to be dependent of network types which are being implemented. In this work, recommendations are made based upon the types of network and capacity of information.

Comparative Study and Packet Error Rate Analysis of Advance Modulation Schemes for Optical Wireless Communication Networks

In this paper, we are going to emphasize on the advancement in computing technology cloud computing is an incredible innovation to perform complex processing It decreases the need of costly equipment’s and dedicated storage The connection between information and cloud  computing is inspected along The definition, attributes and grouping of huge information along with certain discourses on cloud computing are presented with focus on accessibility, information honesty, information quality, adaptability, security and administration There is a rapid development in cloud computing and Internet of things regard the field of wireless communication We present a survey on the security issues of both the technologies We studied about the contributions of cloud computing to the Internet of things technology It will illustrate the improvements on the internet of things on the basis of cloud We will discuss the pros and cons of merging the technologies The financial effects on innovation will be discussed, it will mainly emphasize on macroeconomics development In this examination the results of rivalry and market structures will be brought to spotlight Secondly the impact on industries and firms renting the storage from the providers will be discussed and how it effects the economics Vehicular networking has become a significant area due to standardization, traffic management, road safety and infotainment Vehicles carry more communication systems in sensing power It can promote intelligent transportation system Vehicular cloud computing remarkably effects traffic, the executives and street security in a split by utilizing the vehicular assets

https://sujo2.usindh.edu.pk/index.php/USJICT/article/download/357/224

Qasim Ali

Papers

DPMM: dynamic pseudonym-based multiple mix-zones generation for mobile traveler

Comparative Study and Packet Error Rate Analysis of Advance Modulation Schemes for Optical Wireless Communication Networks

A survey on cloud computing, security Challenges, architecture, applications & solutions