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Optical fiber communication network security is getting more and more prominent, while the optical fiber communication network monitoring is another challenges of the optical fiber communication network security. In order to Address Resolution Protocol key technology was used. In addition, design of optical fiber communication network detection system was also designed. [ABSTRACT FROM AUTHOR]

We take a model-theoretic viewpoint on security goals and how to establish them. The models are (possibly fragmentary) executions. Security goals such as authentication and confidentiality are geometric sequents, i.e. implications Φ→Ψ where Φ and Ψ are built from atomic formulas without negations, implications, or universal quantifiers.Security goals are then statements about homomorphisms, where the source is a minimal (fragmentary) model of the antecedent Φ. If every homomorphism to a non-fragmentary, complete execution factors through a model in which Ψ is satisfied, then the goal is achieved. One can validate security goals via a process of information enrichment. We call this approach enrich-by-need protocol analysis.This idea also clarifies protocol transformation. A protocol transformation preserves security goals when it preserves the form of the information enrichment process. We formalize this idea using simulation relations between labeled transition systems. These labeled transition systems formalize the analysis of the protocols, i.e. the information enrichment process, not the execution behavior of the protocols. [ABSTRACT FROM AUTHOR]

We present a new type system for verifying the security of reference implementations of cryptographic protocols written in a core functional programming language. The type system combines prior work on refinement types, with union, intersection, and polymorphic types, and with the novel ability to reason statically about the disjointness of types. The increased expressivity enables the analysis of important protocol classes that were previously out of scope for the type-based analyses of reference protocol implementations. In particular, our types can statically characterize: (i) more usages of asymmetric cryptography, such as signatures of private data and encryptions of authenticated data; (ii) authenticity and integrity properties achieved by showing knowledge of secret data; (iii) applications based on zero-knowledge proofs. The type system comes with a mechanized proof of correctness and an efficient type-checker. [ABSTRACT FROM AUTHOR]

This paper is motivated by the observation that existing security models for direct anonymous attestation (DAA) have problems to the extent that insecure protocols may be deemed secure when analysed under these models. This is particularly disturbing as DAA is one of the few complex cryptographic protocols resulting from recent theoretical advances actually deployed in real life. Moreover, standardization bodies are currently looking into designing the next generation of such protocols. Our first contribution is to identify issues in existing models for DAA and explain how these errors allow for proving security of insecure protocols. These issues are exhibited in all deployed and proposed DAA protocols (although they can often be easily fixed). Our second contribution is a new security model for a class of 'pre-DAA scheme', that is, DAA schemes where the computation on the user side takes place entirely on the trusted platform. Our model captures more accurately than any previous model the security properties demanded from DAA by the trusted computing group (TCG), the group that maintains the DAA standard. Extending the model from pre-DAA to full DAA is only a matter of refining the trust models on the parties involved. Finally, we present a generic construction of a DAA protocol from new building blocks tailored for anonymous attestation. Some of them are new variations on established ideas and may be of independent interest. We give instantiations for these building blocks that yield a DAA scheme more efficient than the one currently deployed, and as efficient as the one about to be standardized by the TCG which has no valid security proof. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with device connections in a trust-based ad hoc network. Because a temporary device frequently joins or leaves a network, the authentication and security technology should be prepared for the malicious devices used in third-party attacks. An authentication scheme with the existing certification and ID, and security technology using symmetric and public keys are used. Therefore, in this paper we propose using two devices that have not shared information for mutual generation of authentication ID. The use of an authentication ID can establish mutual trust and provide security and efficiency for communication and generation of a symmetric key. Our analysis results show that an authentication operation reduction of up to 57%, compared to related work, is achieved by our protocol. [Copyright &y& Elsevier]

Although the objective of secure communication can be achieved by using cryptographic tools, the undeniability that results from cryptographic properties may create a potential threat to the sender of the message. Unfortunately, most existing deniable protocols only provide 1-out-of-2 deniability. When both parties (the sender and the receiver) are allowed to deny generating the message, a dispute might occur between these two parties. The 1-out-of-2 deniable protocol can result in an unfair resolution of the dispute. Therefore, we propose a new model of deniability, called 1-out-of-∞ deniability, that can provide full deniability. The 1-out-of-∞ deniability protocol allows the originator of the message to deny that he or she generated the message, since there are an infinite number of possible message generators; at the same time, all transmitted messages can be protected and authenticated between the sender and the intended receiver. Our design can be implemented by using any public-key cryptography technique. We also analyze the correctness of the proposed protocols based on logical rules, and two practical examples are given to illustrate our design. [ABSTRACT FROM AUTHOR]

Authenticated multiple key exchange protocols not only allow participants to agree the multiple session keys within one run of the protocol but also ensure the authenticity of the other party. In this paper, we propose an identity-based multiple key exchange protocol. The authentication part of the proposed protocol is provably secure in the random oracle model under the BDH assumptions. The proposed identity-based multiple key exchange protocol is secure in a formal security model under the random oracle model upon the CDH assumptions and the BDH assumptions. Compared with the identity-based multiple key exchange protocols in the literature, the proposed protocol is more efficient and holds stronger security. [ABSTRACT FROM AUTHOR]

Abstract: In 2008, Lee et al. proposed two multiple-key agreement protocols, first one based on elliptic curve cryptography (ECC) and the other one, based on bilinear pairings. Shortly after publication, Vo et al. showed that the Lee–Wu–Wang’s pairing-based protocol is vulnerable to impersonation attack then for removing the problem, they proposed an improved protocol. In this paper, first We show that the Lee–Wu–Wang’s ECC-based protocol is insecure against forgery attack and also, if long-term private keys of two entities and one key of the session keys are revealed, the other session keys are exposed too. Then, we demonstrate that the Vo–Lee–Yeun–Kim’s protocol is vulnerable to another kind of forgery attacks and a reflection attack. [Copyright &y& Elsevier]

Abstract: The radio-based medium of satellite communication systems is vulnerable to interference on physical channels: unintentional interferences occur frequently and jamming attacks can be achieved using low-grade technology. While application layer security protocols cannot defend against denial of service (DoS) attacks where the attacker jams continuously, effective security protocols ensure that communication can continue after such interference has stopped. This paper analyses an authentication and key agreement protocol for satellite communications. The presented analysis reveals that the protocol is susceptible to a new DoS attack, where attackers jam a single message to achieve a permanent DoS condition. A new authentication and key agreement protocol is proposed that additionally addresses the scenario where messages send over the mobile satellite channel may not reach their intended recipient due to accidental or malicious interference. Analysis of the new protocol demonstrates that it is effective in countering the disruptive effects of jamming. [Copyright &y& Elsevier]

Abstract: Group key agreement is the core of secure group communication. In wireless networks, the privacy problem becomes more crucial and urgent for mobile users due to the open nature of radio media. In this paper, we proposed a novel group key agreement protocol based on trusted third Party, applied in collaboration between mobile users for wireless Mesh network. The security verification (PCL logic) and performance analysis show that, our protocol not only provides privacy protection for group members, but also authenticates all participants by adopting certificates. More important, in the proposed protocol, the computation cost and traffics for each group member are largely reduced to improve the implementation efficiency of the protocol. Therefore, our protocol is a novel, reliable group key agreement protocol, and it is well suited for wireless mesh network. [Copyright &y& Elsevier]

Abstract: In 2010, Vo et al. (2010) proposed an enhancement of authenticated multiple key exchange protocol based on Lee et al.’s protocol. In this paper, we will show that Vo et al.’s multiple key exchange protocol cannot resist reflection attack. It means that their protocol fails to provide mutual authentication. Furthermore, we propose an improvement of Vo et al.’s protocol. Our proposed protocol with reflection attack resilience can really provide mutual authentication. [Copyright &y& Elsevier]

Abstract: In this paper, we present a strongly secure identity-based (ID-based) two-party authenticated key agreement (AKA) protocol, which captures all basic desirable security properties including master key forward secrecy, ephemeral secrets reveal resistance and so on, and is provably secure in the extended Canetti–Krawczyk (eCK) model. The security of the protocol can be reduced to the standard Computational Bilinear Diffie–Hellman assumption in the random oracle model. Our scheme is secure as long as each party has at least one uncompromised secret. Also, we give a strongly secure variant of the protocol. The variant has a much lower computational overhead than the original scheme, while its security relies on the Gap Bilinear Diffie–Hellman assumption. Currently, there are few ID-based AKA protocols that are provably secure in the strong eCK model. Compared with previous ID-based AKA schemes, our protocols have advantages over them in security or efficiency. [Copyright &y& Elsevier]

We study private computations in information-theoretical settings on networks that are not 2-connected. Non-2-connected networks are 'non-private' in the sense that most functions cannot privately be computed on them. We relax the notion of privacy by introducing lossy private protocols, which generalize private protocols. We measure the information each player gains during the computation. Good protocols should minimize the amount of information they lose to the players. Throughout this work, privacy always means 1-privacy, i.e. players are not allowed to share their knowledge. Furthermore, the players are honest but curious, thus they never deviate from the given protocol. The randomness used by the protocol yields distributions on communication strings for each player and for each input. We define the loss of a protocol to a player as the logarithm of the number of different probability distributions the player can observe. This is justified since we prove that in optimal protocols, the distributions have pairwise disjoint support. Thus, the players can easily distinguish them, and the logarithm of their number is the number of bits the player learns. The simplest non-2-connected networks consists of two blocks that share one bridge node. We prove that on such networks, communication complexity and the loss of a private protocol are closely related: Up to constant factors, they are the same. Then we study one-phase protocols, an analogue of one-round communication protocols. In such a protocol each bridge node may communicate with each block only once. We investigate in which order a bridge node should communicate with the blocks to minimize the loss of information. In particular, for symmetric functions it is optimal to sort the components by increasing size. Then we design a one-phase protocol that for symmetric functions simultaneously minimizes the loss at all nodes where the minimum is taken over all one-phase protocols. Finally, we prove a phase hierarchy. For any k there is a function such that every ( k−1)-phase protocol for this function has an information loss that is exponentially greater than that of the best k-phase protocol. [ABSTRACT FROM AUTHOR]

The paper is devoted to the design of a test suite for testing the conformance of implementations of Internet nodes to the specifications of the new security protocol IPsec v2 [1-7]. The test suite is generated using the automated testing technology UniTESK [8] and the package CTesK [9], which implements this technology. The work was performed in the Institute for System Programming of the Russian Academy of Sciences within the project 'Verification of security functions for the new generation protocol IPsec v2.' Requirements for the implementations of IPsec v2 were systemized, and formal specifications and a prototype of the test suite for the verification of implementations of IPsec v2, including implementations of the automatic generation of security associations of IKEv2, were developed. A method used to formalize the requirements for IPsec v2, a procedure for generating the test suite, and testing results for some available implementations are described. The results show that the verification method proposed in this paper effectively automates the testing of such complex protocols as security protocols. [ABSTRACT FROM AUTHOR]

Abstract: Password-based authentication is widely used for systems that control remote access to computer networks. In order to address some of the security and management problems that occur in traditional password authentication protocols, research in recent decades has focused on smart card based password authentication. In this paper, we show that the improved smart card authentication scheme proposed by Xu-Zhu-Feng is vulnerable to internal and impersonation attacks. We propose an improvement of their solution, present a new efficient strong smart card authentication protocol, and demonstrate that the new protocol satisfies the requirements of strong smart card authentication and is more efficient. [Copyright &y& Elsevier]

Abstract: Key management is an important building block for all security operations in sensor networks. Most existing key management schemes try to establish shared keys for all pairs of neighbor sensors; hence, a large number of keys need to be preloaded on each sensor, which necessitates a large key space for the nodes in the network. The recent trend in research is to mainly consider homogeneous sensor networks, and to a lesser degree heterogeneous sensor networks, for key management. In this paper, we propose a novel key agreement protocol which is based on pairing-based cryptography over an elliptic curve. Using this protocol, any two nodes that need to communicate can independently compute the same secret key by using pairing and identity-based encryption properties. The proposed protocol significantly reduces the key space of a node. Additionally, the security analysis of the proposed protocol shows that it is robust against a number of attacks including wormhole attack, masquerade attacks, reply attacks, and message manipulation attacks. [Copyright &y& Elsevier]

Peer-to-peer (P2P) networks are vulnerable to peers who cheat, propagate malicious code, leech on the network, or simply do not cooperate. The traditional security techniques developed for the centralized distributed systems like client-server networks are insufficient for P2P networks by the virtue of their centralized nature. The absence of a central authority in a P2P network poses unique challenges for reputation management in the network. These challenges include identity management of the peers, secure reputation data management, Sybil attacks, and above all, availability of reputation data. In this paper, we present a cryptographic protocol for ensuring secure and timely availability of the reputation data of a peer to other peers at extremely low costs. The past behavior of the peer is encapsulated in its digital reputation, and is subsequently used to predict its future actions. As a result, a peer's reputation motivates it to cooperate and desist from malicious activities. The cryptographic protocol is coupled with self-certification and cryptographic mechanisms for identity management and countering Sybil attack. We illustrate the security and the efficiency of the system analytically and by means of simulations in a completely decentralized Gnutella-like P2P network. [ABSTRACT FROM AUTHOR]

Conformity to prudent design principles is an established approach to protocol correctness although it is not free of limitations. We term goal availability a design principle that is often implicitly followed, prescribing protocols to aim at principal-centric goals. Adherence to a design principle is normally established through protocol analysis that is an evaluation of whether a protocol achieves its goals. However, the literature shows that there exists no clear guidance on how to conduct and interpret such an analysis, a process that is only left to the analyzer’s skill and experience. Goal availability has the desirable feature that its supporting protocol analysis can be precisely guided by what becomes a principle of realistic analysis, which we call guarantee availability. It prescribes that the outcome of the analysis, which is the set of guarantees confirming the protocol goals, be practically applicable by the protocol participants. In consequence, the guarantees must be based on assumptions that the principals have the capacity to verify. Our focus then turns entirely to protocol analysis, because an analysis conforming to guarantee availability signifies that the analyzed protocol conforms to goal availability. Existing analysis of (both classical and deployed) protocols has been reconsidered with the aim of studying their conformity to guarantee availability. Some experiments clarify the relationships between goal availability and the existing design principles, with particular reference to explicitness. Other experiments demonstrate that boosting an analysis with guarantee availability generally makes it deeper, unveiling additional protocol niceties that depending on the analyzer’s skills may remain overseen otherwise. In particular, an established claim about a protocol (made using a well-known formal method) can be subverted. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel gateway (GW) selection protocol in hybrid Mobile Ad hoc Networks (MANETs). We focus on the situation that occurs when specialized, sensitive data is sent to the Internet from MANET nodes. These special data types are especially susceptible to security risks such as information leak and data falsification. Therefore, it is necessary for such special data to be forwarded by a secure/trusted GW which is controlled by a trusted network administrator. However, there should be multiple GWs deployed in a MANET, where the cost ineffectiveness makes it difficult for a network administrator to simultaneously manage every GW. Because of the risk of forwarding special data through an unmaintained GW, we propose a routing protocol which allows a source node to have sensitive data forwarded to the Internet through a trusted GW. To achieve this desirable performance, we improve upon one of the newest routing protocols, Dynamic MANET On-demand (DYMO), which works in consideration of application data. Through simulations, we evaluate our protocol in comparison with the conventional DYMO protocol. The results show that our protocol can make MANET source nodes choose GWs for specific data. [ABSTRACT FROM AUTHOR]

Mobile Ad-hoc NETworks (MANETs) are expected to play an important role in tactical military networks by providing infrastructureless communication. However, maintaining secure and instant information sharing is a difficult task especially for highly dynamic military MANETs. To address this requirement, we propose a new multi-tier adaptive military MANET security protocol using hybrid cryptography and signcryption. In our protocol, we bring novelties to secure military MANET communication for three main points: Cryptographic methods used in MANETs, hybrid key management protocols and structural organization of the military MANETs. As a new approach, we use hybrid cryptography mechanisms and Elliptic Curve Pintsov-Vanstone Signature Scheme (ECPVS8) that provide security and performance advantages when compared to some traditional cryptographic methods. Furthermore, multi-leveled security approach of our protocol provides adaptive solutions according to the requirements of different military units in the MANET. We also use a hybrid key management technique that combines the benefits of both decentralized protocols with single point of failure resistivity and centralized protocols with low rekeying cost. Last, the proposed network structure facilitates certification and key management for the MANET by providing flexibility for Mobile Backbone Network (MBN) tiers. [ABSTRACT FROM AUTHOR]

Utilising the battery life and the limited bandwidth available in mobile ad hoc networks (MANETs) in the most efficient manner is an important issue, along with providing security at the network layer. The authors propose, design and describe E2-SCAN, an energy-efficient network layered security solution for MANETs, which protects both routing and packet forwarding functionalities in the context of the on demand distance vector protocol. E2-SCAN is an advanced approach that builds on and improves upon some of the state-of-the-art results available in the literature. The proposed E2-SCAN algorithm protects the routing and data forwarding operations through the same reactive approach, as is provided by the SCAN algorithm. It also enhances the security of the network by detecting and reacting to the malicious nodes. In E2-SCAN, the immediate one-hop neighbour nodes collaboratively monitor. E2-SCAN adopts a modified novel credit strategy to decrease its overhead as the time evolves. Through both analysis and simulation results, the authors demonstrate the effectiveness of E2-SCAN over SCAN in a hostile environment. [ABSTRACT FROM AUTHOR]

Security has become one of the major issues for data communication over wired and wireless networks. Different from the past work on the designs of cryptography algorithms and system infrastructures, we will propose a dynamic routing algorithm that could randomize delivery paths for data transmission. The algorithm is easy to implement and compatible with popular routing protocols, such as the Routing Information Protocol in wired networks and Destination-Sequenced Distance Vector protocol in wireless networks, without introducing extra control messages. An analytic study on the proposed algorithm is presented, and a series of simulation experiments are conducted to verify the analytic results and to show the capability of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Abstract: In the last years the amount of information being transmitted through communication networks has increased, and this has lead to an increased use of security protocols. The implementations of security protocols do not accurately follow the standards and this causes many malfunctions and security flaws. In this paper we will analyze the different approaches followed by the scientific community to evaluate security protocols'' implementations, and will also analyze the special characteristics of security protocols, in order to deduce which are the key points for such an evaluation, how they can be evaluated and also if existing evaluation techniques can be used. [Copyright &y& Elsevier]

Abstract: In many network applications, including distant learning, audio webcasting, video streaming, and online gaming, often a source has to send data to many receivers. IP multicasts and application-layer multicasts provide efficient and scalable one-to-many or many-to-many communications. A common secret key, the group key, shared by multiple users can be used to secure the information transmitted in the multicast communication channel. In this paper, a new group key management protocol is proposed to reduce the communication and computation overhead of group key rekeying caused by membership changes. With shared key derivation, new keys derivable by members themselves do not have to be encrypted or delivered by the server, and the performance of synchronous and asynchronous rekeying operations, including single join, single leave, and batch update, is thus improved. The proposed protocol is shown to be secure and immune to collusion attacks, and it outperforms the other comparable protocols from our analysis and simulation. The protocol is particularly efficient with binary key trees and asynchronous rekeying, and it can be tuned to meet different rekeying delay or key size requirements. [Copyright &y& Elsevier]

We address two issues of contemporary interest in the area of enhancing the performance of ad hoc networks, where the IEEE 802.11 distributed coordination function (DCF) is the adopted medium-access control (MAC). We investigate the effects that transmission power control and tuning carrier sensing (CS) threshold have on network throughput, and we study the inter- play between them. To accomplish this, we develop a realistic analytical model that characterizes the transmission activities that are governed by the IEEE 802.11 DCF in a single-channel power-aware multihop wireless network. We observe that selecting a smaller CS threshold will severely impact the spatial reuse, whereas a larger CS threshold will yield excessive interference among concurrent transmissions. Accordingly, we discovered that performing power control has either a minor or negligible effect in both situations, respectively. Furthermore, when the CS threshold is selected appropriately, power control shows its effectiveness in reducing collisions and, hence, improving system performance. Finally, using our model, we demonstrate the potential adverse impacts of request-to-send/clear-to-send (RTS/CTS) control packets on the network capacity and compare its performance with the two-way basic access method. [ABSTRACT FROM AUTHOR]

The secrecy problem for security protocols is the problem to decide whether or not a given security protocol has leaky runs. In this paper, the (initial) secrecy problem for bounded protocols with freshness check is shown to be NEXPTIME-complete. Relating the formalism in this paper to the multiset rewriting (MSR) formalism we obtain that the initial secrecy problem for protocols in restricted form, with bounded length messages, bounded existentials, with or without disequality tests, and an intruder with no existentials, is NEXPTIME-complete. If existentials for the intruder are allowed but disequality tests are not allowed, the initial secrecy problem still is NEXPTIME-complete. However, if both existentials for the intruder and disequality tests are allowed and the protocols are not well-founded (and, therefore, not in restricted form), then the problem is undecidable. These results also correct some wrong statements in Durgin et al., JCS 12 (2004), 247–311. [ABSTRACT FROM AUTHOR]

Abstract: The rights of an Internet user acting anonymously conflicts with the rights of a Server victim identifying the malicious user. The ERPINA protocol, introduced in this paper, allows an honest user communicating anonymously with a Server through a PET, while the identity of a dishonest user is revealed. Prior research failed to distinguish objectively between an honest user and an attacker; and a reliable and objective distinguishing technique is lacking. The ERPINA protocol addresses the reliability issue efficiently by defining from the beginning of the communication what is considered as malicious and what is not. [Copyright &y& Elsevier]

We introduce the Game-Theoretic Stochastic Routing (GTSR) framework, a proactive alternative to today's reactive approaches to route repair. GTSR minimizes the impact of link and router failure by 1) computing multiple paths between source and destination and 2) selecting among these paths randomly to forward packets. Besides improving fault tolerance, the fact that GTSR makes packets take random paths from source to destination also improves security. In particular, it makes connection eavesdropping attacks maximally difficult as the attacker would have to listen on all possible routes. The approaches developed are suitable for network layer routing, as well as for application layer overlay routing and multipath transport protocols such as the Stream Control Transmission Protocol (SCTP). Through simulations, we validate our theoretical results and show how the resulting routing algorithms perform in terms of the security/fault-tolerant/delay/throughput trade-off. We also show that a beneficial side effect of these algorithms is an increase in throughput, as they make use of multiple paths. [ABSTRACT FROM AUTHOR]

We present three case studies, investigating the use of probabilistic model checking to automatically analyse properties of probabilistic contract signing protocols. We use the probabilistic model checker PRISM to analyse three protocols: Rabin's probabilistic protocol for fair commitment exchange; the probabilistic contract signing protocol of Ben-Or, Goldreich, Micali, and Rivest; and a randomised protocol for signing contracts of Even, Goldreich, and Lempel. These case studies illustrate the general methodology for applying probabilistic model checking to formal verification of probabilistic security protocols. For the Ben-Or et al. protocol, we demonstrate the difficulty of combining fairness with timeliness. If, as required by timeliness, the judge responds to participants' messages immediately upon receiving them, then there exists a strategy for a misbehaving participant that brings the protocol to an unfair state with arbitrarily high probability, unless unusually strong assumptions are made about the quality of the communication channels between the judge and honest participants. We quantify the tradeoffs involved in the attack strategy, and discuss possible modifications of the protocol that ensure both fairness and timeliness. For the Even et al. protocol, we demonstrate that the responder enjoys a distinct advantage. With probability 1, the protocol reaches a state in which the responder possesses the initiator's commitment, but the initiator does not possess the responder's commitment. We then analyse several variants of the protocol, exploring the tradeoff between fairness and the number of messages that must be exchanged between participants. [ABSTRACT FROM AUTHOR]

The article discusses the application of Security Assertion Markup Language (SAML) to protect Session Initiation Protocol (SIP) in voice over Internet Protocol signaling. SAML standard was used to supports the expression of security assertions which include authentication, role membership, or permissions. The flexibility of SAML assertions allows for the encoding of the identity imformation about the user, its generic authentication and authorization attributes to accommodate full authorization mechanisms and enable trait-based authorization. Moreover, SIP can be used together with SAML which was reflected in the present standardization work within the Internet Engineering Task Force.

The article discusses the results of the study on the methods of protecting the session initiation protocol (SIP) from information leak exposures which is used for voice over Internet Protocol signaling. Several forms of the exploitation of implementation vulnerabilities involve unauthorized access, worms, viruses, and denial of service attacks. The researchers introduced techniques to fingerprint SIP devices and develop a fingerprinting tool called SIPProbe that gathered fingerprints and determine SIP implementations. The study showed several useful applications of SIP fingerprinting such as higher priority given to messages from voice gateways, customization of messages for specific user agents, and slow processing of messages that are suspected to be malicious.

Abstract: In recent years, several protocols for password-based authenticated key exchange have been proposed. These protocols aim to be secure even though the sample space of passwords may be small enough to be enumerated by an off-line adversary. In Eurocrypt 2000, Bellare, Pointcheval and Rogaway (BPR) presented a model and security definition for authenticated key exchange. They claimed that in the ideal-cipher model (random oracles), the two-flow protocol at the core of Encrypted Key Exchange (EKE) is secure. Bellare and Rogaway suggested several instantiations of the ideal cipher in their proposal to the IEEE P1363.2 working group. Since then there has been an increased interest in proving the security of password-based protocols in the ideal-cipher model. For example, Bresson, Chevassut, and Pointcheval have recently showed that the One-Encryption-Key-Exchange (OEKE) protocol is secure in the ideal cipher model. In this paper, we present examples of real (NOT ideal) ciphers (including naive implementations of the instantiations proposed to IEEE P1363.2) that would result in broken instantiations of the idealised AuthA protocol and OEKE protocol. Our result shows that the AuthA protocol can be instantiated in an insecure way, and that there are no well defined (let alone rigorous) ways to distinguish between secure and insecure instantiations. Thus, without a rigorous metric for ideal-ciphers, the value of provable security in ideal cipher model is limited. [Copyright &y& Elsevier]

Abstract: We show how cryptographic protocols using Diffie–Hellman primitives, i.e., modular exponentiation on a fixed generator, can be encoded in Horn clauses modulo associativity and commutativity. In order to obtain a sufficient criterion of security, we design a complete (but not sound in general) resolution procedure for a class of flattened clauses modulo simple equational theories, including associativity–commutativity. We report on a practical implementation of this algorithm in the MOP modular platform for automated proving; in particular, we obtain the first fully automated proof of security of the IKA.1 initial key agreement protocol in the so-called pure eavesdropper model. [Copyright &y& Elsevier]

Abstract: To enable the verification of authentication protocols, Schneider formulated the rank function approach which could be used, under suitable circumstances, to verify protocols modelled using the process algebra CSP. We develop this theoretical result and extend it to a practical framework which can be used to model and analyse a wider variety of security protocols with respect to a wider range of security specifications than were hitherto possible. These results are achieved using PVS, which also provides tool support for the rank function approach. [Copyright &y& Elsevier]

We discuss the strengths and weaknesses of existing tools with respect to the Internet Protocol security (IPsec) name mapping problem: how to ensure a correct mapping between application-layer target names and network-layer target names. We show that DNSSEC is neither necessary nor sufficient for solving the IPsec name mapping problem. We describe design and implementation results for new techniques that are applicable to legacy applications to partially or completely solve the IPsec name mapping problem. As a corollary, we obtain programming recommendations that make it easier to apply these techniques. We show how the set of current IPsec policy parameters can usefully be expanded. We give a prototype of a modified lookup API and argue that the modified API is the preferred long-term solution to the IPsec name mapping problem. We also cover the implications for IPsec key management. Finally, we summarize the environments where IPsec is being used today and discuss which IPsec name mapping techniques are most appropriate for these environments. [ABSTRACT FROM AUTHOR]

Non‐interference has been advocated by various authors as a uniform framework for the formal specification of security properties in cryptographic protocols. Unfortunately, specifications based on non‐interference are often non‐effective, as they require protocol analyses in the presence of all possible intruders. This paper develops new characterizations of non‐interference that rely on a finitary representation of intruders. These characterizations draw on equivalence relations built on top of labelled transition systems in which the presence of intruders is accounted for, indirectly, in terms of their (the intruders') knowledge of the protocols' initial data. The new characterizations apply uniformly to trace and bisimulation non‐interference, yielding proof techniques for the analysis of various security properties. We demonstrate the effectiveness of such techniques in the analysis of different properties of a fair exchange protocol. [ABSTRACT FROM AUTHOR]

When formalizing security protocols, different specification languages support very different reasoning methodologies, whose results are not directly or easily comparable. Therefore, establishing clear mappings among different frameworks is highly desirable, as it permits various methodologies to cooperate by interpreting theoretical and practical results of one system into another. In this paper, we examine the relationship between two general verification frameworks: multiset rewriting (MSR) and a process algebra (PA) inspired to CCS and the π‐calculus. Although defining a simple and general bijection between MSR and PA appears difficult, we show that the sublanguages needed to specify cryptographic protocols admit an effective translation that is not only trace‐preserving, but also induces a correspondence relation between the two languages. In particular, the correspondence sketched in this paper permits transferring several important trace‐based properties such as secrecy and many forms of authentication. [ABSTRACT FROM AUTHOR]

An important problem in the analysis of security protocols is that of checking whether a protocol preserves secrecy, i.e., no secret owned by the honest agents is unintentionally revealed to the intruder. This problem has been proved to be undecidable in several settings. In particular, Durgin et al. prove the undecidability of the secrecy problem in the presence of an unbounded set of nonces, even when the message length is bounded. In this paper we prove that even in the presence of an unbounded set of nonces the secrecy problem is decidable for a reasonable subclass of protocols, which we call context‐explicit protocols. [ABSTRACT FROM AUTHOR]

Authentication protocols help to establish trust about the identities of communicating entities. Along with authorization and data confidentiality, authentication forms a critical component of most non-trivial security frameworks. Over past several years, an alarming number of seemingly secure authentication protocols have been shown to be flawed. By exploiting such flaws, malicious entities can potentially take on identities of trusted entities. Attacks on authentication protocols are often too subtle to uncover by simple means, hence considerable research has gone into techniques for analyzing and verifying them. Though the problem is perhaps best studied using formal methods, techniques in that category are generally rather complex and specialized. This paper proposes a different approach - using simulation as a means of validation. Though unable to conclusively prove security, simulation can be very effective in uncovering hidden flaws. This could be particularly useful for large systems where it may be nearly impractical to apply formal methods. A framework is presented to model authentication protocols with state machines and to validate some of their security properties through simulation. [ABSTRACT FROM AUTHOR]

IP traceback is a technique to combat distributed denial of service attacks. This technique can specify the routers in the path of the attack flow with forged source addresses. Although several techniques have been proposed to solve this problem, a variety of problems arise when operating on the actual Internet. We proposed a hierarchical architecture for IP traceback as a solution to these problems. In this paper, we define each type of protocol, design architecture for a prototype implementation, and verify its operation. Based on the results, we found that a large-scale simulation was needed. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(11): 49–56, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10202 [ABSTRACT FROM AUTHOR]

We present the first type and effect system for proving authenticity properties of security protocols based on asymmetric cryptography. The most significant new features of our type system are: (1) a separation of public types (for data possibly sent to the opponent) from tainted types (for data possibly received from the opponent) via a subtype relation; (2) trust effects, to guarantee that tainted data does not, in fact, originate from the opponent; and (3) challenge/response types to support a variety of idioms used to guarantee message freshness. We illustrate the applicability of our system via protocol examples. [ABSTRACT FROM AUTHOR]

We formalize the Dolev–Yao model of security protocols, using a notation based on multiset rewriting with existentials. The goals are to provide a simple formal notation for describing security protocols, to formalize the assumptions of the Dolev–Yao model using this notation, and to analyze the complexity of the secrecy problem under various restrictions. We prove that, even for the case where we restrict the size of messages and the depth of message encryption, the secrecy problem is undecidable for the case of an unrestricted number of protocol roles and an unbounded number of new nonces. We also identify several decidable classes, including a DEXP‐complete class when the number of nonces is restricted, and an NP‐complete class when both the number of nonces and the number of roles is restricted. We point out a remaining open complexity problem, and discuss the implications these results have on the general topic of protocol analysis. [ABSTRACT FROM AUTHOR]

There is increasing growth in the number of computer networks in use and in the kinds of distributed computing applications available on these networks. This increase, together with concern about privacy, security, and integrity of information exchange, has created considerable interest in the use of encryption to protect information in the networks. This survey is directed at the reader who is knowledgeable about various network designs and who now wishes to consider incorporating encryption methods into these designs. It is also directed at developers of encryption algorithms who wish to understand the characteristics of such algorithms useful in network applications. Key management, network encryption protocols, digital signatures, and the utility of conventional-or public-key encryption methods are each discussed. A case study of how encryption was integrated into an actual network, the Arpanet, illustrates many issues present in the design of a network encryption facility. [ABSTRACT FROM AUTHOR]

Abstract: The APSSNMP network management protocol was proposed as a secure alternative to the Simple Network Management Protocol (SNMP) used in the TCP/IP suite. The designers claimed that it resists meet-in-the-middle (MITM) attacks. In this paper, we present an advanced MITM attack on the APSSNMP and hence show that it fails to achieve its design objective of providing better security against MITM attacks. Since the APSSNMP has been presented in several journals, and IEEE and IASTED conferences, our result is important to highlight to network implementers and users of distributed systems that the APSSNMP is not secure for practical deployment. [Copyright &y& Elsevier]

The article discusses digital storage devices, or transient storage devices (TSD). Businesses need authentication of these devices before they allow a host to mount them due to security issues. The Institute of Electrical & Electronics Engineers' (IEEE) Computer Society has developed a protocol for standards in authentication for TSDs. The IEEE directive states that the host can authenticate TSD's identity and the TSD can also authenticate the host's identity. Analysts say authentication will solve many problems associated with the spread of TSDs.