Extensible Hashing

Secure environments protect the resources against unauthorized access by enforcing access control mechanisms. Therefore, when increasing security is an issue, text based passwords are not enough to counter such problems. Security has always been an issue since Internet and Web Development came into existence, numeric based passwords is not enough to counter such problems, which is also an out dated approach now. Therefore, this demands the need for something more secure along with being more userfriendly. Therefore, we have tried to increase the security by involving an image based authentication approach, involving text based password , Image Based Authentication and automated generated one-time password (received through an automated process on mobile of the authentic user). And an assiduous effort has been done for preventing Shoulder attack, Tempest attack, and Brute-force attack at client side , through the use of unique image in the Image Based Authentication (IBA) System for ...

A cluster-based server consists of a front-end dispatcher and multiple back-end servers. The dispatcher receives incoming jobs, and then decides how to assign them to back-end servers, which in turn serve the jobs according to some discipline. Clusterbased servers have been widely deployed, as they combine good performance with low costs. Several assignment policies have been proposed for cluster-based servers, most of which aim to balance the load among back-end servers. There are two main strategies for load balancing: The first aims to balance the amount of work at back-end servers, while the second aims to balance the number of jobs assigned to back-end servers. Examples of policies using these strategies are Dynamic and LC (Least Connected), respectively. In this paper we propose a policy, called LC*, which combines the two aforementioned strategies. The paper shows experimentally that when preemption is admitted (i.e., when jobs execute concurrently on back-end servers), LC* substantially outperforms both Dynamic and LC in terms of response time metrics. This improved performance is achieved by using only information readily available to the dispatcher, rendering LC* a practical policy to implement. Finally, we study a refinement, called ALC* (Adaptive LC*), which further improves on the response-time performance of LC* by adapting its actions to incoming traffic rates.

Department of Information Technology, JSPM’s Rajarshi Shahu College of Engineering, Savitribai Phule Pune University Tathawade, Pune, Maharashtra ( India) ABSTRACT In this paper,we present an approach using cued click point (CCP) under graphical password that permits to enrich authentication technique of graphical password in(CCP). Our literature studies shows various limitations for textual passwords, they are exposed to shoulder surfing attack however strong textual passwords are tough to memorize. Graphical Passwords are introduced to resist the Shoulder surfing attack. .Looking at the success of this system , using graphical password as input and grid lines for image point verificationand enrich it to provide security using normal login and graphical password. This system can be used in the field such as banking application, military application, civilians, forensic labs, etc.

A password is a sequence of characters used to determine whether the user is authenticated or not. Nowadays most of the password is text-based. Since text based password is hard to remember people try to use simple memorable password such as pet names, phone number, etc. which are easy to break by intruders. The main idea behind the paper is to replace the text-based passwords by image based password and encrypt using RSA algorithm. Our experimental result shows that image passwords are easy to remember, better than the text.

This paper presents modelling of the basic authentication procedure. The Petri net technique as a tool was chosen in this study. Experiments were made with two groups of models according the quantity of used attributes. One consists of combination of the User name and Password with and/or without repeating. The second group consist of the user name, password and biometrics with and/or without repeating. The goal of this paper is to demonstrate that security increasing with attributes quantity and decreasing with possibility to repeating wrong sequence of symbols.

A cluster-based server consists of a front-end dispatcher and several back-end servers. The dispatcher receives incoming requests, and then assigns them to back-end servers for processing. Our goal is to devise an assignment policy that has good response time performance, and is practical to implement in that the amount of information used by the dispatcher is relatively small, so that the attendant computation and communication overheads are low. In contrast to extant assignment policies that apply the same assignment policy to all incoming jobs, our approach calls for the dispatcher to classify incoming jobs as long or short, and then use class-dependent assignment policies. Specifically, we propose a policy, called CDA (Class Dependent Assignment), where short jobs are assigned in Round-Robin manner as soon as they arrive, while long jobs are deferred and assigned only when a back-end server becomes idle. Furthermore, when processing a long job, a back-end server is not assigned any other jobs. Our approach is motivated by empirical evidence suggesting that the sizes of files traveling on the Internet follow power-law distributions, where long jobs constituting a small fraction of all incoming jobs actually account for a large fraction of the overall load. To gauge the performance of the proposed policy, we exercised it on empirical data traces measured at Internet sites serving the 1998 World Cup. Since the assignment of long jobs incurs computational overhead * Work supported in part by DIMACS under contract STC-91-19999, and

Alphanumerical usernames and passwords are the most used computer authentication technique. This approach has been found to have a number of disadvantages. Users, for example, frequently choose passwords that are simple to guess. On the other side, if a password is difficult to guess, it is also difficult to remember. Graphical passwords have been proposed in the literature as a potential alternative to alphanumerical passwords, based on the fact that people remember pictures better than text. Existing graphical passwords, on the other hand, are vulnerable to a shoulder surfing assault. To address this shoulder surfing vulnerability, this study proposes an authentication system for web-applications based on visual cryptography and cued click point recall-based graphical password. The efficiency of the proposed system was validated using unit, system and usability testing measures. The results of the system and unit testing showed that the proposed system accomplished its objectives ...

Most Web and other on-line service providers ("Internet Services") only support legacy ID (or email) and password (ID/PW) credential authentication. However, there are numerous vulnerabilities concerning ID/PW credentials. Scholars and the industry have proposed several improved security solutions, such as MFA, however most of the Internet Services have refused to adopt these solutions. Mobile phones are much more sensitive to these vulnerabilities (so this paper focuses on mobile phones). Many users take advantage of password managers, to keep track of all their Internet Service profiles. However, the Internet Service profiles found in password managers, are normally kept on the PC or mobile phone's disk, in an encrypted form. Our first contribution is a design guideline, whereby the Internet Service profiles never need to touch the client's disk. Most users would benefit, if they had the ability to use MFA, to login to a legacy Internet Service, which only supports ID/PW credential authentication. Our second contribution is a design guideline, whereby users can choose, for each legacy ID/PW Internet Service, which specific MFA they wish to use. We have also presenting conceptual design guidelines, showing that both of our contributions are minor changes to existing password managers, which can be implemented easily with low overhead.

This paper proposes a new scheduling policy for cluster-based servers called DAS (Deferred Assign-ment Scheduling). The main idea in DAS is to defer scheduling as much as possible, in order to make better use of the accumulated information on job sizes. In broad outline, DAS operates as follows: (1) incoming jobs are held by the dispatcher in a buffer; (2) the dispatcher monitors the number of jobs being processed by each server; (3) when the number of jobs at a server queue drops below a prescribed threshold, the dispatcher sends to it the shortest job in its buffer. To gauge the efficacy of DAS, the paper presents simulation studies, using various data traces. The studies collected response times and slowdowns for two cluster configurations under multi-threaded and multi-process back-end server architectures. The experimental results show that in both archi-tectures, DAS outperforms the Round-Robin policy in all traffic regimes, and the JSQ (Join Shortest Queue) policy in medium a...

This paper proposes a new scheduling policy for cluster-based servers called DAS (Deferred Assignment Scheduling). The main idea in DAS is to defer scheduling as much as possible, in order to make better use of the accumulated information on job sizes. In broad outline, DAS operates as follows: (1) incoming jobs are held by the dispatcher in a buffer; (2) the dispatcher monitors the number of jobs being processed by each server; (3) when the number of jobs at a server queue drops below a prescribed threshold, the dispatcher sends to it the shortest job in its buffer. To gauge the efficacy of DAS, the paper presents simulation studies, using various data traces. The studies collected response times and slowdowns for two cluster configurations under multi-threaded and multi-process back-end server architectures. The experimental results show that in both architectures, DAS outperforms the Round-Robin policy in all traffic regimes, and the JSQ (Join Shortest Queue) policy in medium and heavy traffic regimes.

This paper describes a new scheduling algorithm to distribute jobs in server farm systems. The proposed algorithm overcomes the starvation caused by SRPT (Shortest Remaining Processing Time). This algorithm is used in process scheduling in operating system approach. The algorithm was developed to be used in dispatcher scheduling. This algorithm is non-preemptive discipline, similar to SRPT, in which the priority

Most Web and other on-line service providers ("Internet Services") only support legacy ID (or email) and password (ID/PW) credential authentication. However, there are numerous vulnerabilities concerning ID/PW credentials. Scholars and the industry have proposed several improved security solutions, such as MFA, however most of the Internet Services have refused to adopt these solutions. Mobile phones are much more sensitive to these vulnerabilities (so this paper focuses on mobile phones). Many users take advantage of password managers, to keep track of all their Internet Service profiles. However, the Internet Service profiles found in password managers, are normally kept on the PC or mobile phone's disk, in an encrypted form. Our first contribution is a design guideline, whereby the Internet Service profiles never need to touch the client's disk. Most users would benefit, if they had the ability to use MFA, to login to a legacy Internet Service, which only supports ID/PW credential authentication. Our second contribution is a design guideline, whereby users can choose, for each legacy ID/PW Internet Service, which specific MFA they wish to use. We have also presenting conceptual design guidelines, showing that both of our contributions are minor changes to existing password managers, which can be implemented easily with low overhead.

An electronic tender (e-tender) system is a system in which selling, buying and providing contract by the government with the help of online software. In this system the tender data is recorded, stored and processed primarily as digital information. In the modern world e-tender system is increasing speedily and the popularity of e-tender system need quality and security. In this paper a ‘KBETS’ is proposed which provides user to participating in tender nevertheless of the geographic locations and without worrying about security.

Most Web and other on-line service providers ("Internet Services") only support legacy ID (or email) and password (ID/PW) credential authentication. However, there are numerous vulnerabilities concerning ID/PW credentials. Scholars and the industry have proposed several improved security solutions, such as MFA, however most of the Internet Services have refused to adopt these solutions. Mobile phones are much more sensitive to these vulnerabilities (so this paper focuses on mobile phones). Many users take advantage of password managers, to keep track of all their Internet Service profiles. However, the Internet Service profiles found in password managers, are normally kept on the PC or mobile phone's disk, in an encrypted form. Our first contribution is a design guideline, whereby the Internet Service profiles never need to touch the client's disk. Most users would benefit, if they had the ability to use MFA, to login to a legacy Internet Service, which only supports ID/PW credential authentication. Our second contribution is a design guideline, whereby users can choose, for each legacy ID/PW Internet Service, which specific MFA they wish to use. We have also presenting conceptual design guidelines, showing that both of our contributions are minor changes to existing password managers, which can be implemented easily with low overhead.

Alphanumerical usernames and passwords are the most used computer authentication technique. This approach has been found to have a number of disadvantages. Users, for example, frequently choose passwords that are simple to guess. On the other side, if a password is difficult to guess, it is also difficult to remember. Graphical passwords have been proposed in the literature as a potential alternative to alphanumerical passwords, based on the fact that people remember pictures better than text. Existing graphical passwords, on the other hand, are vulnerable to a shoulder surfing assault. To address this shoulder surfing vulnerability, this study proposes an authentication system for web-applications based on visual cryptography and cued click point recall-based graphical password. The efficiency of the proposed system was validated using unit, system and usability testing measures. The results of the system and unit testing showed that the proposed system accomplished its objectives ...

A cluster-based server consists of a front-end dispatcher and several back-end servers. The dispatcher receives incoming requests, and then assigns them to back-end servers for processing. Our goal is to devise an assignment policy that has good response time performance, and is practical to implement in that the amount of information used by the dispatcher is relatively small, so that the attendant computation and communication overheads are low. In contrast to extant assignment policies that apply the same assignment policy to all incoming jobs, our approach calls for the dispatcher to classify incoming jobs as long or short, and then use class-dependent assignment policies. Specifically, we propose a policy, called CDA (Class Dependent Assignment), where short jobs are assigned in Round-Robin manner as soon as they arrive, while long jobs are deferred and assigned only when a back-end server becomes idle. Furthermore, when processing a long job, a back-end server is not assigned any other jobs. Our approach is motivated by empirical evidence suggesting that the sizes of files traveling on the Internet follow power-law distributions, where long jobs constituting a small fraction of all incoming jobs actually account for a large fraction of the overall load. To gauge the performance of the proposed policy, we exercised it on empirical data traces measured at Internet sites serving the 1998 World Cup. Since the assignment of long jobs incurs computational overhead * Work supported in part by DIMACS under contract STC-91-19999, and

By enforcing access control mechanisms, secure environments protect their resources against unauthorized access. When security is high priority issue, text based passwords are not sufficient. The access provided with the help of only text password is not effective and secure enough. The need for something more secure along with being user friendly is required. The integration of cued click point (CCP) with the Kerberos authentication protocol is a solution. The proposed work combines all the benefits of text based password authentication system with CCP and the Kerberos authentication protocol. Administrator will give the credential according to the need of the user. Kerberos credentials will give the proper login to the system as well as application. User can access the designed system as well as other applications.In this system a password consists of sequence of some images in which user can select one click-point per image. In addition user will be asked to select a sound signature. This sound signature will be used to help the user to signify that the login to the system is successful or not.

In today's world all the customers want instantaneous answers to their queries or services that they've asked for and every other company is racing against time to serve the customer request as soon as possible. Companies have a set of servers to answer their queries but the problem is how to assign these requests to servers in the most optimized way. If we assign all the requests to one server then it might crash and others might sit idle, hence to overcome all such problems we need a balancer to balance the load in an optimized way and this is done by a load balancer. Finding a better algorithm for a load balancer is becoming a hot topic of research and therefore a lot of such algorithms are available. This paper evaluates and compares some most important algorithms for load balancing.

Web servers commonly use cluster-based architectures which combine good performance and low cost. A cluster-based server consists of a front-end dispatcher and several back-end servers. The dispatcher receives incoming requests, and then assigns them to back-end servers for processing, which in turn serve the requests according to some discipline.

The most critical property exhibited by a heavy-tailed workload distribution (found in many WWW workloads) is that a very small fraction of tasks make up a large fraction of the workload, making the load very difficult to distribute in a distributed system. Load balancing and load sharing are the two predominant load distribution strategies used in such systems. Load sharing generally has better response time than load balancing because the latter can exhibit excessive overheads in selecting servers and partitioning tasks. We therefore further explored the Least-Loaded-First (LLF) load sharing approach and found two important limitations: (a) LLF does not consider the order of processing, and (b) when it assigns a task, LLF does not consider the processing capacity of servers. The high task size variation that exists in heavy-tailed workloads often causes smaller tasks to be severely delayed by large tasks. This paper proposes a size-based approach, called the least flow-time first (LFF-SIZE), which reduces the delay caused by size variation while maintaining a balanced load in the system. LFF-SIZE takes the relative processing time of a task into account and dynamically assigns a task to the fittest server with a lighter load and higher processing capacity. LFF-SIZE also uses a multi-section queue to separate larger tasks from smaller ones. This arrangement effectively reduces the delay of smaller tasks by larger ones as small tasks are given a higher priority to be processed. The performance results performed on the LFF-SIZE implementation shows a substantial improvement over existing load sharing and static size-based approaches under realistic heavy-tailed workloads.

Data intensive computing, in the Web environment, motivates the distributed designs of Web server systems (Web clusters) because of their scalability and cost-effectiveness instead of one Web server with high performance. The task assignment policy, in such systems, focuses on the manner of assigning the tasks that reach these systems (e.g. the case of intensive requests that reach the distributed Web server systems) in order to minimize the response time and thus, improve the performance. These tasks, generally, follow the ''heavy-tailed'' distribution which has the property that there is a tiny fraction (about 3%) of large tasks that makes half (50%) of the total load. Several policies were proposed in the literature to deal with the nature of this Web traffic. This paper presents a state-of-art of the existing task assignment policies. We classify these policies in two classes: policies which assume that the task size is known a priori, and policies which assume that the task size is not known a priori (like TAGS, TAPTF and TAPTF-WC). The first class of policies regroups policies which consider no knowledge of load information at the servers when assigning the incoming tasks, known as static policies (like Random, Round Robin, etc.) and, policies, known as dynamic policies (like Central Queue Policy, Least Loaded First ''LLF'', etc.) which use some load information (e.g. the processing capacity, the queue load, etc.) to process.

this paper describes a new scheduling algorithm to distribute jobs in server farm systems .The proposed algorithm overcomes the starvation caused by SRPT (Shortest Remaining Processing Time). This algorithm is used in process scheduling in operating system approach . The algorithm was developed to be used in dispatcher scheduling. This algorithm is non-preemptive discipline, similar to SRPT, in which the priority of each job depends on its estimated run time, and also the amount of time it has spent on waiting. Tasks in the servers are served in order of priority to optimize the system response time. The experiments show that the mean round around time is reduced in the server farm system.

A cluster-based server consists of a front-end dispatcher and several back-end servers. The dispatcher receives incoming requests, and then assigns them to back-end servers for processing. Our goal is to devise an assignment policy that has good response time performance, and is practical to implement in that the amount of information used by the dispatcher is relatively small, so that the attendant computation and communication overheads are low. In contrast to extant assignment policies that apply the same assignment policy to all incoming jobs, our approach calls for the dispatcher to classify incoming jobs as long or short, and then use class-dependent assignment policies. Specifically, we propose a policy, called CDA (Class Dependent Assignment), where short jobs are assigned in Round-Robin manner as soon as they arrive, while long jobs are deferred and assigned only when a back-end server becomes idle. Furthermore, when processing a long job, a back-end server is not assigned any other jobs.

Abstract Passwords are the most common authentication scheme today. However, it is difficult for people to memorize strong passwords, such as random sequences of characters. Additionally, passwords do not provide protection against phishing attacks. This paper introduces WebTicket, a low cost, easy-to-use and reliable web account management system that uses" tickets", which are tokens that contain a two-dimensional barcode that can be printed or stored on smartphones.

The most critical property exhibited by a heavy-tailed workload distribution (found in many WWW workloads) is that a very small fraction of tasks make up a large fraction of the workload, making the load very difficult to distribute in a distributed system. Load balancing and load sharing are the two predominant load distribution strategies used in such systems. Load sharing generally has better response time than load balancing because the latter can exhibit excessive overheads in selecting servers and partitioning tasks.