3,352 research outputs found
User authentication in distributed computing using proactive two-party signatures.
To address the challenges of user authentication in distributed systems, many protocols have been proposed. Among them is the Proactive Two-party Signatures Scheme (P2SS). P2SS has not so far been investigated in detail. Using P2SS, I have developed a system, called Proactive User-authentication in a Distributed Environment (PUDE) in which two parties (the client and server) use a 2-part signature algorithm, based on standard (one part) RSA algorithm. In this scheme the client and the server jointly produce the signatures. If the password of the user is compromised, the system can recover by changing the share of the private key and the password on the primary server only. To test PUDE, a basic multi-realm test-bed called the Secure Multi-realm System (SMS) has been designed. PUDE is able to bring out the usefulness of a proactive two-party signature scheme over different realms. Its security is based on the unacceptable high computational effort required for computing discrete logs. This is a widely-accepted basis of security for security protocols. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2003 .S53. Source: Masters Abstracts International, Volume: 42-03, page: 0973. Adviser: A. K. Aggarwal. Thesis (M.Sc.)--University of Windsor (Canada), 2003
Security and Privacy Issues in Wireless Mesh Networks: A Survey
This book chapter identifies various security threats in wireless mesh
network (WMN). Keeping in mind the critical requirement of security and user
privacy in WMNs, this chapter provides a comprehensive overview of various
possible attacks on different layers of the communication protocol stack for
WMNs and their corresponding defense mechanisms. First, it identifies the
security vulnerabilities in the physical, link, network, transport, application
layers. Furthermore, various possible attacks on the key management protocols,
user authentication and access control protocols, and user privacy preservation
protocols are presented. After enumerating various possible attacks, the
chapter provides a detailed discussion on various existing security mechanisms
and protocols to defend against and wherever possible prevent the possible
attacks. Comparative analyses are also presented on the security schemes with
regards to the cryptographic schemes used, key management strategies deployed,
use of any trusted third party, computation and communication overhead involved
etc. The chapter then presents a brief discussion on various trust management
approaches for WMNs since trust and reputation-based schemes are increasingly
becoming popular for enforcing security in wireless networks. A number of open
problems in security and privacy issues for WMNs are subsequently discussed
before the chapter is finally concluded.Comment: 62 pages, 12 figures, 6 tables. This chapter is an extension of the
author's previous submission in arXiv submission: arXiv:1102.1226. There are
some text overlaps with the previous submissio
Introducing Accountability to Anonymity Networks
Many anonymous communication (AC) networks rely on routing traffic through
proxy nodes to obfuscate the originator of the traffic. Without an
accountability mechanism, exit proxy nodes risk sanctions by law enforcement if
users commit illegal actions through the AC network. We present BackRef, a
generic mechanism for AC networks that provides practical repudiation for the
proxy nodes by tracing back the selected outbound traffic to the predecessor
node (but not in the forward direction) through a cryptographically verifiable
chain. It also provides an option for full (or partial) traceability back to
the entry node or even to the corresponding user when all intermediate nodes
are cooperating. Moreover, to maintain a good balance between anonymity and
accountability, the protocol incorporates whitelist directories at exit proxy
nodes. BackRef offers improved deployability over the related work, and
introduces a novel concept of pseudonymous signatures that may be of
independent interest.
We exemplify the utility of BackRef by integrating it into the onion routing
(OR) protocol, and examine its deployability by considering several
system-level aspects. We also present the security definitions for the BackRef
system (namely, anonymity, backward traceability, no forward traceability, and
no false accusation) and conduct a formal security analysis of the OR protocol
with BackRef using ProVerif, an automated cryptographic protocol verifier,
establishing the aforementioned security properties against a strong
adversarial model
Spectrum sharing security and attacks in CRNs: a review
Cognitive Radio plays a major part in communication technology by resolving the shortage of the spectrum through usage of dynamic spectrum access and artificial intelligence characteristics. The element of spectrum sharing in cognitive radio is a fundament al approach in utilising free channels. Cooperatively communicating cognitive radio devices use the common control channel of the cognitive radio medium access control to achieve spectrum sharing. Thus, the common control channel and consequently spectrum sharing security are vital to ensuring security in the subsequent data communication among cognitive radio nodes. In addition to well known security problems in wireless networks, cognitive radio networks introduce new classes of security threats and challenges, such as licensed user emulation attacks in spectrum sensing and misbehaviours in the common control channel transactions, which degrade the overall network operation and performance. This review paper briefly presents the known threats and attacks in wireless networks before it looks into the concept of cognitive radio and its main functionality. The paper then mainly focuses on spectrum sharing security and its related challenges. Since spectrum sharing is enabled through usage of
the common control channel, more attention is paid to the
security of the common control channel by looking into its
security threats as well as protection and detection mechanisms. Finally, the pros and cons as well as the comparisons of different CR - specific security mechanisms are presented with some open research issues and challenges
Recommended from our members
A two‐step authentication framework for Mobile ad hoc networks
The lack of fixed infrastructure in ad hoc networks causes nodes to rely more heavily on peer nodes for communication. Nevertheless, establishing trust in such a distributed environment is very difficult, since it is not straightforward for a node to determine if its peer nodes can be trusted. An additional concern in such an environment is with whether a peer node is merely relaying a message or if it is the originator of the message. In this paper, we propose an authentication approach for protecting nodes in mobile ad hoc networks. The security requirements for protecting data link and network layers are identified and the design criteria for creating secure ad hoc networks using several authentication protocols are analyzed. Protocols based on zero knowledge and challenge response techniques are presented and their performance is evaluated through analysis and simulation
Password Cracking and Countermeasures in Computer Security: A Survey
With the rapid development of internet technologies, social networks, and
other related areas, user authentication becomes more and more important to
protect the data of the users. Password authentication is one of the widely
used methods to achieve authentication for legal users and defense against
intruders. There have been many password cracking methods developed during the
past years, and people have been designing the countermeasures against password
cracking all the time. However, we find that the survey work on the password
cracking research has not been done very much. This paper is mainly to give a
brief review of the password cracking methods, import technologies of password
cracking, and the countermeasures against password cracking that are usually
designed at two stages including the password design stage (e.g. user
education, dynamic password, use of tokens, computer generations) and after the
design (e.g. reactive password checking, proactive password checking, password
encryption, access control). The main objective of this work is offering the
abecedarian IT security professionals and the common audiences with some
knowledge about the computer security and password cracking, and promoting the
development of this area.Comment: add copyright to the tables to the original authors, add
acknowledgement to helpe
The Value of User-Visible Internet Cryptography
Cryptographic mechanisms are used in a wide range of applications, including
email clients, web browsers, document and asset management systems, where
typical users are not cryptography experts. A number of empirical studies have
demonstrated that explicit, user-visible cryptographic mechanisms are not
widely used by non-expert users, and as a result arguments have been made that
cryptographic mechanisms need to be better hidden or embedded in end-user
processes and tools. Other mechanisms, such as HTTPS, have cryptography
built-in and only become visible to the user when a dialogue appears due to a
(potential) problem. This paper surveys deployed and potential technologies in
use, examines the social and legal context of broad classes of users, and from
there, assesses the value and issues for those users
- …