The Experts below are selected from a list of 264 Experts worldwide ranked by ideXlab platform

Leana Golubchik - One of the best experts on this subject based on the ideXlab platform.

  • Data Assignment in Fault Tolerant Uploads for Digital Government Applications: A Genetic Algorithms Approach
    6th Annual National Conference on Digital Government Research (dg.o 2005), 2005
    Co-Authors: Yan Yang, Leslie Cheung, Leana Golubchik
    Abstract:

    This paper investigates a data assignment problem in a fault tolerance protocol of Bistro, a wide area upload framework. Uploads correspond to an important class of applications, whose examples include a large number of digital government applications. Specifically, government at all levels is a major collector and provider of data, and there are clear benefits to disseminating and collecting data over the Internet, given its existing large-scale infrastructure and wide-spread reach in commercial, private, and government domains. In this project we focus on the collection of data over the Internet. By data collection, we mean applications such as Internal Revenue Service (IRS) applications with respect to electronic submission of income tax forms.In Bistro, clients upload their data to intermediaries, known as bistros, to reduce the traffic to the Destination around a deadline. The Destination Server then computes a schedule for pulling the data from bistros after the deadline. In the Bistro framework, bistros can be unavailable or malicious. Thus, a fault tolerance protocol is a vital and fundamental component of the Bistro framework. In this paper, we are particularly interested in a data assignment problem in the Bistro fault tolerance protocol. We formulate this problem into a non-linear optimization problem and develop a genetic algorithm heuristic as an approximation. We evaluate our approach using simulations and compare the results of our heuristic with other simple heuristics as well as an optimal solution obtained from a brute-force approach.

  • ISPA - A fault tolerance protocol for uploads: design and evaluation
    Parallel and Distributed Processing and Applications, 2004
    Co-Authors: L. Cheung, Leana Golubchik, Cheng-fu Chou, Ye Yang
    Abstract:

    This paper investigates fault tolerance issues in Bistro, a wide area upload architecture. In Bistro, clients first upload their data to intermediaries, known as bistros. A Destination Server then pulls data from bistros as needed. However, during the Server pull process, bistros can be unavailable due to failures, or they can be malicious, i.e., they might intentionally corrupt data. This degrades system performance since the Destination Server may need to ask for retransmissions. As a result, a fault tolerance protocol is needed within the Bistro architecture. Thus, in this paper, we develop such a protocol which employs erasure codes in order to improve the reliability of the data uploading process. We develop analytical models to study reliability and performance characteristics of this protocol, and we derive a cost function to study the tradeoff between reliability and performance in this context. We also present numerical results to illustrate this tradeoff.

  • Bistro: a scalable and secure data transfer service for digital government applications
    Communications of the ACM, 2003
    Co-Authors: Leana Golubchik, Cheng-fu Chou, William C. Cheng, Samir Khuller, Hanan Samet, C. Justin Wan
    Abstract:

    Government at all levels is a major collector and provider of data.Our project focuses on the collection of data over wide-area networks (WANs) and addresses the scalability issues that arise in the context of Internet-based massive data collection applications. Furthermore, security, due to the need for privacy and integrity of the data, is a central issue for data collection applications that use a public infrastructure such as the Internet. Numerous digital government applications require data collection over WANs [5].One compelling example of such an application is the Internal Revenue Service's electronic submission of income tax forms. Other digital government applications include collecting census data, federal statistics, and surveys; gathering and tallying of electronic votes; collecting crime data for the U.S. Justice department; collecting data from sensors for disaster response applications; collecting data from geological surveys; collecting electronic filings of patents, permits, and securities (for SEC) applications; grant proposals and contract bids submissions; and so on. All these applications have scalability and security needs in common.The poor performance that may be experienced by current digital government users, given the existing state of technology (as in Figure 1a), is largely due to how (independent) data transfers using TCP/IP work over the Internet. TCP/IP is good at equally sharing bandwidth between data streams, which in large-scale applications can lead to poor performance for individual clients (as they receive only a very small share of this bandwidth). Given that TCP/IP is here to stay for the foreseeable future, what is needed is a scalable yet cost- effective solution that can be easily deployed over the existing Internet technology.We are designing and developing a system called Bistro, which addresses the scalability needs of digital government data collection applications while allowing them to share the same infrastructure and resources efficiently, cost-effectively, and securely [1]. Bistro's basic approach is to introduce intermediate hosts---bistros---which allow replacement of a traditionally "synchronized client push" approach with a "nonsynchronized combination of client-push and Server-pull" approach (as depicted in Figure 1b). This in turn allows spreading of the workload on the Destination Server and the network over time, with subsequent elimination of hot spots as well as significant improvements in performance for both clients and Servers. Our ongoing research [2, 4] indicates that orders of magnitude of improvement can be achieved with the Bistro architecture and the corresponding data collection algorithms it affords.Bistro's design allows for a gradual deployment and experimentation over the Internet (by simply downloading Bistro Server software and installing it on public Servers). Bistro's security protocol and trust structure [3] are designed such that only encrypted data travels through (not necessarily trusted) bistros. This means a government agency does not need to trust bistros installed by other agencies or commercial institutions. At the same time, these (untrusted) bistros can significantly improve the agency's data collection performance. Each application (within each agency) can have its own scalability, security, fault tolerance, and other data collection needs, and these applications and agencies can still share available resources, if so desired, across all Bistro Servers.We believe an appropriately designed single infrastructure such as Bistro can address all digital government wide-area data collection needs in a scalable, secure, and cost-effective manner. (For more information, see bourbon.usc.edu/iml/bistro/.

  • Scalable designs of wide-area upload applications and distributed continuous media systems
    2002
    Co-Authors: Cheng-fu Chou, Leana Golubchik
    Abstract:

    Rapid advances in digital signal processing, data compression techniques, commodity computer systems and high speed communication networks have made many data intensive applications across the Internet (such as multimedia applications, web downloads, software distribution) an active research area. In this dissertation, our research focuses on following two main areas: (1) Bistro: a Scalable and Secure Infrastructure for Wide-area Uploads. Hotspots are a major obstacle to achieving scalability in the Internet; they are usually caused by either high demand for some data or high demand for a certain service. At the application layer, hotspot problems have traditionally been dealt with using some combination of increasing capacity, spreading the load over time and/or space, and changing the workload. Some examples of these are data replication (web caching, ftp mirroring), data replacement (multi-resolution images, video), service replication (DNS lookup, Network Time Protocol), and Server push (news or software distribution). These classes of solutions have been studied in the context of applications using the following types of communication: (a) one-to-many (data travels primarily from a Server to multiple clients, e.g., web download, software distribution, video-on-demand); (b) many-to-many (data travels between multiple clients, through either a centralized or a distributed Server, e.g., chat rooms, video conferencing); and (c) one-to-one (data travels between two clients, e.g., e-mail, e-talk). However, to the best of our knowledge there is no existing work, except ours, on making applications using many-to-one communication scalable and efficient at the application layer; existing solutions, such as web based uploads, simply use many independent one-to-one transfers. This corresponds to an important class of applications, whose examples include the various upload applications such as submission of income tax forms to IRS, conference paper submission, proposal submission through the NSF FastLane, homework and project submissions in distance education, Internet-based storage, and many more. The main focus of our work is scalable infrastructure design for wide-area upload applications. This area encompasses a broad range of challenging topics including (a) the basic framework and general solution for wide-area upload applications, (b) Server selection problems, (c) providing for security needs of upload applications, (d) large-scale data collection, (e) cost-effective resource management and allocation techniques, (f) provision of fault tolerance schemes to ensure that all data arrives at the Destination Server in the face of failures or malicious behavior by the hosts or elsewhere in the network, and so on. My dissertation addresses topics (a)–(d). Remaining topics are part of ongoing and future efforts. (2)  Continuous Media Servers. Multimedia applications (such as video stream delivery, digital libraries, and distance learning systems) place high demands for quality-of-service (QoS), performance, and reliability on storage Servers and communication networks. These, often stringent, requirements make design of cost-effective and scalable continuous media (CM) Servers difficult. Therefore, the main focus of my work is to provide an efficient adaptive and dynamic resource management techniques in conjunction with data placement techniques in order to improve performance, scalability and reliability of such systems. In this work, we propose to use dynamic replication techniques in conjunction with a “hybrid data placement” technique to design a scalable CM Server. Through a performance study, we show that not only does this hybrid design with dynamic replication techniques result in a scalable, cost-effective CM Server, but it also suggests the usefulness of these techniques across a wide range of continuous media applications.

Cheng-fu Chou - One of the best experts on this subject based on the ideXlab platform.

  • ISPA - A fault tolerance protocol for uploads: design and evaluation
    Parallel and Distributed Processing and Applications, 2004
    Co-Authors: L. Cheung, Leana Golubchik, Cheng-fu Chou, Ye Yang
    Abstract:

    This paper investigates fault tolerance issues in Bistro, a wide area upload architecture. In Bistro, clients first upload their data to intermediaries, known as bistros. A Destination Server then pulls data from bistros as needed. However, during the Server pull process, bistros can be unavailable due to failures, or they can be malicious, i.e., they might intentionally corrupt data. This degrades system performance since the Destination Server may need to ask for retransmissions. As a result, a fault tolerance protocol is needed within the Bistro architecture. Thus, in this paper, we develop such a protocol which employs erasure codes in order to improve the reliability of the data uploading process. We develop analytical models to study reliability and performance characteristics of this protocol, and we derive a cost function to study the tradeoff between reliability and performance in this context. We also present numerical results to illustrate this tradeoff.

  • Bistro: a scalable and secure data transfer service for digital government applications
    Communications of the ACM, 2003
    Co-Authors: Leana Golubchik, Cheng-fu Chou, William C. Cheng, Samir Khuller, Hanan Samet, C. Justin Wan
    Abstract:

    Government at all levels is a major collector and provider of data.Our project focuses on the collection of data over wide-area networks (WANs) and addresses the scalability issues that arise in the context of Internet-based massive data collection applications. Furthermore, security, due to the need for privacy and integrity of the data, is a central issue for data collection applications that use a public infrastructure such as the Internet. Numerous digital government applications require data collection over WANs [5].One compelling example of such an application is the Internal Revenue Service's electronic submission of income tax forms. Other digital government applications include collecting census data, federal statistics, and surveys; gathering and tallying of electronic votes; collecting crime data for the U.S. Justice department; collecting data from sensors for disaster response applications; collecting data from geological surveys; collecting electronic filings of patents, permits, and securities (for SEC) applications; grant proposals and contract bids submissions; and so on. All these applications have scalability and security needs in common.The poor performance that may be experienced by current digital government users, given the existing state of technology (as in Figure 1a), is largely due to how (independent) data transfers using TCP/IP work over the Internet. TCP/IP is good at equally sharing bandwidth between data streams, which in large-scale applications can lead to poor performance for individual clients (as they receive only a very small share of this bandwidth). Given that TCP/IP is here to stay for the foreseeable future, what is needed is a scalable yet cost- effective solution that can be easily deployed over the existing Internet technology.We are designing and developing a system called Bistro, which addresses the scalability needs of digital government data collection applications while allowing them to share the same infrastructure and resources efficiently, cost-effectively, and securely [1]. Bistro's basic approach is to introduce intermediate hosts---bistros---which allow replacement of a traditionally "synchronized client push" approach with a "nonsynchronized combination of client-push and Server-pull" approach (as depicted in Figure 1b). This in turn allows spreading of the workload on the Destination Server and the network over time, with subsequent elimination of hot spots as well as significant improvements in performance for both clients and Servers. Our ongoing research [2, 4] indicates that orders of magnitude of improvement can be achieved with the Bistro architecture and the corresponding data collection algorithms it affords.Bistro's design allows for a gradual deployment and experimentation over the Internet (by simply downloading Bistro Server software and installing it on public Servers). Bistro's security protocol and trust structure [3] are designed such that only encrypted data travels through (not necessarily trusted) bistros. This means a government agency does not need to trust bistros installed by other agencies or commercial institutions. At the same time, these (untrusted) bistros can significantly improve the agency's data collection performance. Each application (within each agency) can have its own scalability, security, fault tolerance, and other data collection needs, and these applications and agencies can still share available resources, if so desired, across all Bistro Servers.We believe an appropriately designed single infrastructure such as Bistro can address all digital government wide-area data collection needs in a scalable, secure, and cost-effective manner. (For more information, see bourbon.usc.edu/iml/bistro/.

  • Scalable designs of wide-area upload applications and distributed continuous media systems
    2002
    Co-Authors: Cheng-fu Chou, Leana Golubchik
    Abstract:

    Rapid advances in digital signal processing, data compression techniques, commodity computer systems and high speed communication networks have made many data intensive applications across the Internet (such as multimedia applications, web downloads, software distribution) an active research area. In this dissertation, our research focuses on following two main areas: (1) Bistro: a Scalable and Secure Infrastructure for Wide-area Uploads. Hotspots are a major obstacle to achieving scalability in the Internet; they are usually caused by either high demand for some data or high demand for a certain service. At the application layer, hotspot problems have traditionally been dealt with using some combination of increasing capacity, spreading the load over time and/or space, and changing the workload. Some examples of these are data replication (web caching, ftp mirroring), data replacement (multi-resolution images, video), service replication (DNS lookup, Network Time Protocol), and Server push (news or software distribution). These classes of solutions have been studied in the context of applications using the following types of communication: (a) one-to-many (data travels primarily from a Server to multiple clients, e.g., web download, software distribution, video-on-demand); (b) many-to-many (data travels between multiple clients, through either a centralized or a distributed Server, e.g., chat rooms, video conferencing); and (c) one-to-one (data travels between two clients, e.g., e-mail, e-talk). However, to the best of our knowledge there is no existing work, except ours, on making applications using many-to-one communication scalable and efficient at the application layer; existing solutions, such as web based uploads, simply use many independent one-to-one transfers. This corresponds to an important class of applications, whose examples include the various upload applications such as submission of income tax forms to IRS, conference paper submission, proposal submission through the NSF FastLane, homework and project submissions in distance education, Internet-based storage, and many more. The main focus of our work is scalable infrastructure design for wide-area upload applications. This area encompasses a broad range of challenging topics including (a) the basic framework and general solution for wide-area upload applications, (b) Server selection problems, (c) providing for security needs of upload applications, (d) large-scale data collection, (e) cost-effective resource management and allocation techniques, (f) provision of fault tolerance schemes to ensure that all data arrives at the Destination Server in the face of failures or malicious behavior by the hosts or elsewhere in the network, and so on. My dissertation addresses topics (a)–(d). Remaining topics are part of ongoing and future efforts. (2)  Continuous Media Servers. Multimedia applications (such as video stream delivery, digital libraries, and distance learning systems) place high demands for quality-of-service (QoS), performance, and reliability on storage Servers and communication networks. These, often stringent, requirements make design of cost-effective and scalable continuous media (CM) Servers difficult. Therefore, the main focus of my work is to provide an efficient adaptive and dynamic resource management techniques in conjunction with data placement techniques in order to improve performance, scalability and reliability of such systems. In this work, we propose to use dynamic replication techniques in conjunction with a “hybrid data placement” technique to design a scalable CM Server. Through a performance study, we show that not only does this hybrid design with dynamic replication techniques result in a scalable, cost-effective CM Server, but it also suggests the usefulness of these techniques across a wide range of continuous media applications.

C. Justin Wan - One of the best experts on this subject based on the ideXlab platform.

  • Bistro: a scalable and secure data transfer service for digital government applications
    Communications of the ACM, 2003
    Co-Authors: Leana Golubchik, Cheng-fu Chou, William C. Cheng, Samir Khuller, Hanan Samet, C. Justin Wan
    Abstract:

    Government at all levels is a major collector and provider of data.Our project focuses on the collection of data over wide-area networks (WANs) and addresses the scalability issues that arise in the context of Internet-based massive data collection applications. Furthermore, security, due to the need for privacy and integrity of the data, is a central issue for data collection applications that use a public infrastructure such as the Internet. Numerous digital government applications require data collection over WANs [5].One compelling example of such an application is the Internal Revenue Service's electronic submission of income tax forms. Other digital government applications include collecting census data, federal statistics, and surveys; gathering and tallying of electronic votes; collecting crime data for the U.S. Justice department; collecting data from sensors for disaster response applications; collecting data from geological surveys; collecting electronic filings of patents, permits, and securities (for SEC) applications; grant proposals and contract bids submissions; and so on. All these applications have scalability and security needs in common.The poor performance that may be experienced by current digital government users, given the existing state of technology (as in Figure 1a), is largely due to how (independent) data transfers using TCP/IP work over the Internet. TCP/IP is good at equally sharing bandwidth between data streams, which in large-scale applications can lead to poor performance for individual clients (as they receive only a very small share of this bandwidth). Given that TCP/IP is here to stay for the foreseeable future, what is needed is a scalable yet cost- effective solution that can be easily deployed over the existing Internet technology.We are designing and developing a system called Bistro, which addresses the scalability needs of digital government data collection applications while allowing them to share the same infrastructure and resources efficiently, cost-effectively, and securely [1]. Bistro's basic approach is to introduce intermediate hosts---bistros---which allow replacement of a traditionally "synchronized client push" approach with a "nonsynchronized combination of client-push and Server-pull" approach (as depicted in Figure 1b). This in turn allows spreading of the workload on the Destination Server and the network over time, with subsequent elimination of hot spots as well as significant improvements in performance for both clients and Servers. Our ongoing research [2, 4] indicates that orders of magnitude of improvement can be achieved with the Bistro architecture and the corresponding data collection algorithms it affords.Bistro's design allows for a gradual deployment and experimentation over the Internet (by simply downloading Bistro Server software and installing it on public Servers). Bistro's security protocol and trust structure [3] are designed such that only encrypted data travels through (not necessarily trusted) bistros. This means a government agency does not need to trust bistros installed by other agencies or commercial institutions. At the same time, these (untrusted) bistros can significantly improve the agency's data collection performance. Each application (within each agency) can have its own scalability, security, fault tolerance, and other data collection needs, and these applications and agencies can still share available resources, if so desired, across all Bistro Servers.We believe an appropriately designed single infrastructure such as Bistro can address all digital government wide-area data collection needs in a scalable, secure, and cost-effective manner. (For more information, see bourbon.usc.edu/iml/bistro/.

Kadobayashi Youki - One of the best experts on this subject based on the ideXlab platform.

  • An empirical approach to phishing countermeasures through smart glasses and validation agents
    IEEE, 2019
    Co-Authors: Ndibwile, Jema David, Luhanga, Edith Talina, Fall Doudou, Miyamoto Daisuke, Blanc Gregory, Kadobayashi Youki
    Abstract:

    International audiencePhishing attacks have been persistent for more than two decades despite mitigation efforts from academia and industry. We believe that users fall victim to attacks not only because of lack of knowledge and awareness, but also because they are not attentive enough to security indicators and visual abnormalities on the webpages they visit. This is also probably why smart device users, who have more limited screen size and device capabilities compared to desktop users, are three times more likely to fall victim to phishing attacks. To assert our claim, we first investigated general phishing awareness among different groups of smartphone users. We then used smart eyeglasses (electro-oculographic) to experimentally measure the mental effort and vigilance exhibited by users while surfing a website and while playing an Android phishing game that we developed. The results showed that knowledge and awareness about phishing do not seem to have a significant impact on security behaviours, as knowledgeable participants exhibited insecure behaviours such as opening email attachments from unfamiliar senders. However, attentiveness was important as even participants with low cybersecurity knowledge could effectively identify attacks if they were reasonably attentive. Based on these results, we asserted that users are more likely to continue falling victim to phishing attacks due to insecure behaviours, unless tools to lessen the identification burden are provided. We thus recommended implementing a lightweight algorithm into a custom Android browser for detecting phishing sites deceptively without a user interaction. We used fake login credentials as validation agents and monitor the Destination Server HTTP responses to determine the authenticity of a webpage. We also presented initial evaluation results of this algorithm

Youki Kadobayashi - One of the best experts on this subject based on the ideXlab platform.

  • An empirical approach to phishing countermeasures through smart glasses and validation agents
    IEEE Access, 2019
    Co-Authors: Jema David Ndibwile, Edith Talina Luhanga, Daisuke Miyamoto, Gregory Blanc, Doudou Fall, Youki Kadobayashi
    Abstract:

    Phishing attacks have been persistent for more than two decades despite mitigation efforts from academia and industry. We believe that users fall victim to attacks not only because of lack of knowledge and awareness, but also because they are not attentive enough to security indicators and visual abnormalities on the webpages they visit. This is also probably why smart device users, who have more limited screen size and device capabilities compared to desktop users, are three times more likely to fall victim to phishing attacks. To assert our claim, we first investigated general phishing awareness among different groups of smartphone users. We then used smart eyeglasses (electro-oculographic) to experimentally measure the mental effort and vigilance exhibited by users while surfing a website and while playing an Android phishing game that we developed. The results showed that knowledge and awareness about phishing do not seem to have a significant impact on security behaviours, as knowledgeable participants exhibited insecure behaviours such as opening email attachments from unfamiliar senders. However, attentiveness was important as even participants with low cybersecurity knowledge could effectively identify attacks if they were reasonably attentive. Based on these results, we asserted that users are more likely to continue falling victim to phishing attacks due to insecure behaviours, unless tools to lessen the identification burden are provided. We thus recommended implementing a lightweight algorithm into a custom Android browser for detecting phishing sites deceptively without a user interaction. We used fake login credentials as validation agents and monitor the Destination Server HTTP responses to determine the authenticity of a webpage. We also presented initial evaluation results of this algorithm.