Private Web Search with Malicious Adversaries

Web search engine (WSE) is an inevitable software system used by people worldwide to retrieve data from the web by using keywords called queries. WSE stores search queries to build the user's profile and provide personalized results. User search queries often hold identifiable information that could compromise the user's privacy. Preserving privacy in web searches is the primary concern of users from various backgrounds. Many techniques have been proposed to preserve a person's web search privacy with time. Some techniques preserve an individual's privacy by obfuscating a user's profile by sending fictitious queries with the original ones. Others hide their identity and preserve privacy through unlinkability. However, a distributed technique preserves privacy by providing unlinkability and obfuscation. In distributed protocols, a group of users collaborate to forward each other queries to WSE, providing unlinkability and obfuscation. This work presents a survey of distributed privacy-preserving protocols. The benefits, limitations, and evaluation parameters are detailed in this work.

Distributed networks remarkably enhance the convenience of network connectivity. How to achieve efficient cooperative computation while preserving data privacy is a challenge in the scenario of distributed networks. Secure computation, as the key technology of information security and privacy protection in the distributed networks, attracts more and more attention. In the paper, we develop the protocols of secure two-party computation in the presence of malicious adversaries which are constructed with homomorphic probabilistic cryptosystem, and propose four honest-verifier zero-knowledge proof protocols to detect two cheating behaviours of the malicious adversary. The proposed protocols are more targeted than the existing work. The analysis shows that the proposed protocols are complete, sound and zero-knowledge. As an application, we show how to use our protocols in a secure two-party protocol to detect cheating, which can make it secure in the presence of malicious adversaries.

Internet has become an instant source of informatio n for almost anyone. By viewing the results of sear ch terms displayed by an Internet Search Engine (ISE), a person may decide his next course of action whether to continue using the Internet, abort or to combine it with other sources of information. The results produced by an ISE can be regarded as an in dex of relative availability of references. Given a list of suitable search terms, a user will firstly have to decide on the ISE to be used. Due to huge potent ial references available for given search terms the use r has to create heuristics to choose the entries sh own on the computer screen. As there are varying breadths and depths of information revealed by various Inter net Search Engines (ISE’s), this paper will not attempt to make a comparison among ISE’s, rather will focu s only on a particular search engine and ascertain th e results it produces given a list of search terms. Google is chosen as a proxy, being one of the most popular ISE’s. By confining to only a search engine, the s tudy affords to control variability among ISE’s should m ultiple ISE’s be used. With the search engine place d under control, it is easy to achieve the primary ob jective of the study, i.e., to ascertain availabili ty of relative breadth of sub-themes of Analytic Hierarch y Process (AHP) in Google. It is natural for user, especially researcher to be concerned with number, quantity. If there is seemingly abundant literature , one would be motivated to pursue research along the the me or sub-theme. In this study, the strength of presence of a sub-theme is measured by using two measures: (i) result of a sub-theme of AHP over the sub-theme itself, and (ii) result of the sub-theme over the total results generated for all of the thi rty six sub-themes used in the search. This study controlle d biasness in specifying the sub-themes of AHP by adopting the sub-themes or search terms specified b y the 2013 AHP conference organizers. This decision helps make the study efficient without with it has to distill the sub-themes by surveying the AHP literature. The data for analysis was gathered by s urfing Google on 26 Feb 2013 8.55 p.m. - 9.26 p.m. Peninsular Malaysian time. The search results were computed to generate two types of ratios specified earlier. A composite index was created using the re sulting two types of ratios which are used to class ify the efficiency, hence dominance of the original res ults (hits). Kendall’s correlation produced statist ically significant correlations between the composite inde x and Rank of AHP specific and area results. Using indices greater than 1.000 as the base, 6 AHP specific areas occupy the top positions with ratios ranging from 19.341 to 61.574; 15 AHP specific areas occupy the second top positions with ratios ranging from 1.119 to 9.602, and 14 AHP specific areas occupy the third and last position with indi ces below 1.000 ranging from 0.050 to 0.894. The paper includes dis cussion, implications, limitations, conclusions and suggestions for further research.

The Internet is a huge repository of information. Web search engines are a basic tool for finding and accessing all this information. However, these tools might also be a threat for the privacy of their users. This happens because users frequently reveal private information in their queries. Web search engines gather this personal data, store it during a large period of time and use it to improve their search results and to increase their economical benefits. In order to avoid this situation, it is necessary to provide web search methods that preserve the privacy of the users. Current proposals in the literature increase significantly the query delay. This is the time that users have to wait in order to obtain the search results for their queries. In this paper, we propose a modification of the Useless User Profile (UUP) protocol. The resulting scheme has been tested in an open environment and the results show that it achieves the lowest query delay which has been reported in the literature. In addition to that, it incentivizes users to follow the protocol in order to protect their privacy.

Web search engines (WSEs) build user profiles and use them to offer an enhanced web search experience. Nevertheless, these elements might contain sensitive data that may represent a privacy threat for the users. There are some works in the literature that address this situation while preserving the profile usefulness. These schemes submit synthetic queries that are fake but related to the real general interests of the user. Specifically, they rely on past user queries to obtain the legitimate interests of each user. We argue that this is not always the best strategy and, in this paper, we study the use of social networks to gather this information and provide a better personalized service while offering an equivalent privacy level.

Secure two-party computation provides a way for two parties to compute a function, that depends on the two parties’ inputs, while keeping them private. Known since the 1980s, Yao’s garbled circuits appear to be a general solution to this problem, in the semi-honest model. Decades of optimizations have made this tool a very practical solution. However, it is well known that a malicious adversary could modify a garbled circuit before submitting it. Many protocols, mostly based on cut-&-choose, have been proposed to secure Yao’s garbled circuits in the presence of malicious adversaries. Nevertheless, how much an adversary can modify a circuit and make it still executable has not been studied yet. The main contribution of this paper is to prove that any modification made by an adversary is equivalent to adding/removing NOT gates arbitrarily in the original circuit, otherwise the adversary can get caught. Thereafter, we study some evaluation functions for which, even without using cut-&-choose, no adversary can gain more information about the inputs by modifying the circuit. We also give an improvement over most recent cut-&-choose solutions by requiring that different circuits of the same function are used instead of just one.

In this paper, a new notion which we call private data deduplication protocol, a deduplication technique for private data storage is introduced and formalized. Intuitively, a private data deduplication protocol allows a client who holds a private data proves to a server who holds a summary string of the data that he/she is the owner of that data without revealing further information to the server. Our notion can be viewed as a complement of the state-of-the-art public data deduplication protocols of Halevi et al [7]. The security of private data deduplication protocols is formalized in the simulation-based framework in the context of two-party computations. A construction of private deduplication protocols based on the standard cryptographic assumptions is then presented and analyzed. We show that the proposed private data deduplication protocol is provably secure assuming that the underlying hash function is collision-resilient, the discrete logarithm is hard and the erasure coding algorithm can erasure up to α-fraction of the bits in the presence of malicious adversaries in the presence of malicious adversaries. To the best our knowledge this is the first deduplication protocol for private data storage.

We propose a protocol for the problem of secure two-party pattern matching, where Alice holds a text t?{0,1}? of length n, while Bob has a pattern p?{0,1}? of length m. The goal is for Bob to (only) learn where his pattern occurs in Alice's text, while Alice learns nothing. Private pattern matching is an important problem that has many applications in the area of DNA search, computational biology and more. Our construction guarantees full simulation in the presence of malicious, polynomial-time adversaries (assuming the hardness of DDH assumption) and exhibits computation and communication costs of O(n+m) group elements in a constant round complexity. This improves over previous work by Gennaro et al. (Public Key Cryptography, pp. 145---160, 2010) whose solution requires overhead of O(nm) group elements and exponentiations in O(m) rounds. In addition to the above, we propose a collection of protocols for important variations of the secure pattern matching problem that are significantly more efficient than the current state of art solutions: First, we deal with secure pattern matching with wildcards. In this variant the pattern may contain wildcards that match both 0 and 1. Our protocol requires O(n+m) communication and O(1) rounds using O(nm) computation. Then we treat secure approximate pattern matching. In this variant the matches may be approximated, i.e., have Hamming distance less than some threshold, ?. Our protocol requires O(n?) communication in O(1) rounds using O(nm) computation. Third, we have secure pattern matching with hidden pattern length. Here, the length, m, of Bob's pattern remains a secret. Our protocol requires O(n+M) communication in O(1) rounds using O(n+M) computation, where M is an upper bound on m. Finally, we have secure pattern matching with hidden text length. Finally, in this variant the length, n, of Alice's text remains a secret. Our protocol requires O(N+m) communication in O(1) rounds using O(N+m) computation, where N is an upper bound on n.

This year marks the 30th anniversary since the approval of gadolinium-based contrast agents (GBCAs) for diagnostic use in MRI. To date, well over 300 million doses of GBCAs have been administered to patients and have repeatedly been shown to be safe for use. However, a recent high profile celebrity case of what is being colloquially termed “gadolinium poisoning” has thrust the safety profile of GBCAs into the media spotlight and patient awareness. Gena Norris, wife of retired Hollywood actor and mixed martial artist Chuck Norris, spoke candidly in an interview with CBS news on November 2, 2017 about the symptoms she developed following a contrast-enhanced MRI performed over 5 years ago.1 Both she and her husband have been vocal about GBCAs and addressed the Food and Drug Administration (FDA) in an open letter that was read out before the FDA's vote on gadolinium warning labels in September 2017.2 We would like to take this opportunity to extend our sympathy and support to Mrs. Norris, who, as a patient has undoubtedly experienced distressing symptoms. Previously, high profile celebrity cases have increased the public's awareness of certain health issues. This was most famously demonstrated by what has been dubbed as the “The Angelina Effect” by Time magazine. Hollywood actress, Angelina Jolie, underwent a bilateral prophylactic mastectomy and eventual completion oophorectomy after discovering that she was positive for the BRCA1 gene. A paper published in 2014 found that public demand for BRCA gene testing almost doubled as a result.3 We aimed to ascertain whether the Gena Norris case had an effect on the public's awareness of GBCAs and gadolinium retention by examining recent trends in internet searches. The software Google Trends (Google, Inc.) was used to examine internet trends over the past 5 years for the search terms “gadolinium,” “gadolinium deposition disease,” and the more colloquial term, “gadolinium poisoning.” Google trends provide information on the relative popularity of an internet search term over time. A score of 100 indicates the peak popularity for that search term over the time period selected by the user. A score of 50 indicates a relative popularity equating to 50% of the value for the most popular time for that particular search term. Google trends from January 2013 to January 2018 were examined. The peak popularity for the search terms “gadolinium poisoning” and “gadolinium deposition disease” occurred over the week of October 29–November 4, 2017 (Figure 1). This was the week of the Gena and Chuck Norris interview with CBS about gadolinium agents. The peak popularity for the term “gadolinium” was over the week of November 5–11, 2017, the week after the aforementioned interview, by which time it had been reported on by media outlets worldwide (Figure 1). Combined Google trends graph for search terms “Gadolinium,” “Gadolinium Poisoning,” and “Gadolinium Deposition Disease” from January 2013 to January 2018. The peak search term popularity occurred between the dates October 29–November 11 High profile celebrity health disclosures can cause significant increases in the public health awareness of disease. It is clear from internet search activity that the public are becoming increasingly aware of GBCAs and the perceived risks. This is most likely due, in a large part, to the widely publicized case of Gena Norris. As professionals concerned with the public's perception of MRI, it is of utmost importance to be mindful of this when answering the questions that will inevitably be raised by future patients requiring gadolinium-based contrast-enhanced MRI. We feel that there is a growing need for more readily available patient appropriate information regarding the safety and potential risks associated with gadolinium deposition.

The recent emphasis on shared decision-making has increased the role of the Internet as a readily accessible medical reference source for patients and families. However, the lack of professional review creates concern over the quality, accuracy, and readability of medical information available to patients on the Internet. Three Internet search engines (Google, Yahoo, and Bing) were evaluated prospectively using 3 difference search terms of varying sophistication ("congenital hip dislocation," "developmental dysplasia of the hip," and "hip dysplasia in children"). Sixty-three unique Web sites were evaluated by each of 3 surgeons (2 fellowship-trained pediatric orthopaedic attendings and 1 orthopaedic chief resident) for quality and accuracy using a set of scoring criteria based on the AAOS/POSNA patient education Web site. The readability (literacy grade level) of each Web site was assessed using the Fleisch-Kincaid score. There were significant differences noted in quality, accuracy, and readability of information depending on the search term used. The search term "developmental dysplasia of the hip" provided higher quality and accuracy compared with the search term "congenital hip dislocation." Of the 63 total Web sites, 1 (1.6%) was below the sixth grade reading level recommended by the NIH for health education materials and 8 (12.7%) Web sites were below the average American reading level (eighth grade). The quality and accuracy of information available on the Internet regarding developmental hip dysplasia significantly varied with the search term used. Patients seeking information about DDH on the Internet may not understand the materials found because nearly all of the Web sites are written at a level above that recommended for publically distributed health information. Physicians should advise their patients to search for information using the term "developmental dysplasia of the hip" or, better yet, should refer patients to Web sites that they have personally reviewed for content and clarity. Orthopaedic surgeons, professional societies, and search engines should undertake efforts to ensure that patients have access to information about DDH that is both accurate and easily understandable.

PurposeMicrolearning has been considered as a promising topic in work-based learning. This paper aims to review the trends of microlearning in terms of related publications and Internet searches. Hopefully, the findings can serve as a reference for the education sector, government, business and academia to promote, design and use microlearning.Design/methodology/approachIn this study, two sets of analysis were conducted. Firstly, the authors analysed the publication trend of microlearning. Second, the authors analysed the trend of Internet searches related to microlearning. More specifically, the authors analysed real-world data of 14 years obtained from Scopus and Google Trends for the purpose. These data include the first relevant publication found in the database.FindingsIn total, 476 relevant publications have been identified during 2006–2019. According to the findings from the analysis of the identified publications, microlearning is a relevantly new and emerging global topic involving authors, affiliations and funding sponsors from different countries. Moreover, many microlearning-related publications were conducted from perspectives of e-learning or mobile learning. Furthermore, the authors notice higher education was the most frequently mentioned education level in the identified publications. On the other hand, language learning (i.e. second language, vocabulary learning, etc.) had been mentioned more times in the titles and abstracts than other subject areas. Overall, the increasing trend of publications on “microlearning” (as a knowledge supply) is in line with the established increasing Internet searches of “microlearning” (as a practical demand) in recent years.Practical implicationsFrom the work-based learning perspective, microlearning has been considered as one of the key topics in talent development topics. Policymakers, educators, researchers and participators have the responsibility to explore how to promote, design and use microlearning to help people to learn in the right direction through valid knowledge with ethical consideration.Originality/valueAlthough many works had been done on microlearning, there is a lack of comprehensive studies reviewing the trends of microlearning in terms of related publications and Internet searches. This study aims to fill this gap by analysing real-world data obtained from Scopus and Google Trends – these data include the first relevant publication found in the database. The authors believe this is the first time that a study has been conducted to comprehensively review the development trends of microlearning. Hopefully, this study can shed some light on related research.

Personalized query suggestion based on user behavior

Previous work on understanding user web search behavior has focused on how people search and what they are searching for, but not why they are searching. In this paper, we describe a framework for understanding the underlying goals of user searches, and our experience in using the framework to manually classify queries from a web search engine. Our analysis suggests that so-called navigational" searches are less prevalent than generally believed while a previously unexplored "resource-seeking" goal may account for a large fraction of web searches. We also illustrate how this knowledge of user search goals might be used to improve future web search engines.

General purpose Web search engines can be a valuable tool to locate high quality information and can complement the use of specialized systems, such as LexisNexis or WestLaw. The effective use of Web search engines differs somewhat from that of other information retrieval systems and requires an understanding of search engine design and procedures before effective use. We present an overview of search engines and user behavior in Web searching as an introduction to a discussion of the effectiveness of using some of the advanced searching techniques common in other searching environments in Web searches. We empirically test the effectiveness on query operators for Web searching. The use of operators such as AND, OR, and PHRASE was found to have little or no difference on the number of relevant results retrieved for three major search engines, America Online, Google, and Microsoft Search.

Location-dependent services are services that adapt their behavior based on the locations of mobile devices. For many applications, it is critical that location-dependent services use trustworthy device locations, namely locations that are both accurate and recent. These properties are captured by a security goal called locale authentication whereby an entity can authenticate the physical location of a device, even in the presence of malicious adversaries. In this paper, we present a systematic technique for verifying that location discovery protocols satisfy this security goal. We base our work on the strand space theory which provides a framework for determining which security goals a cryptographic protocol achieves. We extend this theory with a metric that captures the geometric properties of time and space. We use the extended theory to prove that several prominent location discovery protocols including GPS do not satisfy the locale authentication goal. We also analyze a location discovery protocol that does satisfy the goal under some reasonable assumptions.