2,324 research outputs found
Validating a Web Service Security Abstraction by Typing
An XML web service is, to a first approximation, an RPC service in which
requests and responses are encoded in XML as SOAP envelopes, and transported
over HTTP. We consider the problem of authenticating requests and responses at
the SOAP-level, rather than relying on transport-level security. We propose a
security abstraction, inspired by earlier work on secure RPC, in which the
methods exported by a web service are annotated with one of three security
levels: none, authenticated, or both authenticated and encrypted. We model our
abstraction as an object calculus with primitives for defining and calling web
services. We describe the semantics of our object calculus by translating to a
lower-level language with primitives for message passing and cryptography. To
validate our semantics, we embed correspondence assertions that specify the
correct authentication of requests and responses. By appeal to the type theory
for cryptographic protocols of Gordon and Jeffrey's Cryptyc, we verify the
correspondence assertions simply by typing. Finally, we describe an
implementation of our semantics via custom SOAP headers.Comment: 44 pages. A preliminary version appears in the Proceedings of the
Workshop on XML Security 2002, pp. 18-29, November 200
AnBx - Security Protocols Design and Verification
Designing distributed protocols is challenging, as it requires actions at very different levels: from the choice of network-level mechanisms to protect the exchange of sensitive data, to the definition of structured interaction patterns to convey application-specific guarantees. Current security infrastructures provide very limited support for the specification of such guarantees. As a consequence, the high-level security properties of a protocol typically must often be hard-coded explicitly, in terms of low-level cryptographic notions and devices which clutter the design and undermine its scalability and robustness. To counter these problems, we propose an extended Alice & Bob notation for protocol narrations (AnBx) to be employed for a purely declarative modelling of distributed protocols. These abstractions provide a compact specification of the high-level security guarantees they convey, and help shield the design from the details of the underlying cryptographic infrastructure. We discuss an implementation of the abstractions based on a translation from the AnBx notation to the AnB language supported by the OFMC [1,2] verification tool. We show the practical effectiveness of our approach by revisiting the iKP e-payment protocols, and showing that the security goals achieved by our declarative specification outperform those offered by the original protocols
ANCHOR: logically-centralized security for Software-Defined Networks
While the centralization of SDN brought advantages such as a faster pace of
innovation, it also disrupted some of the natural defenses of traditional
architectures against different threats. The literature on SDN has mostly been
concerned with the functional side, despite some specific works concerning
non-functional properties like 'security' or 'dependability'. Though addressing
the latter in an ad-hoc, piecemeal way, may work, it will most likely lead to
efficiency and effectiveness problems. We claim that the enforcement of
non-functional properties as a pillar of SDN robustness calls for a systemic
approach. As a general concept, we propose ANCHOR, a subsystem architecture
that promotes the logical centralization of non-functional properties. To show
the effectiveness of the concept, we focus on 'security' in this paper: we
identify the current security gaps in SDNs and we populate the architecture
middleware with the appropriate security mechanisms, in a global and consistent
manner. Essential security mechanisms provided by anchor include reliable
entropy and resilient pseudo-random generators, and protocols for secure
registration and association of SDN devices. We claim and justify in the paper
that centralizing such mechanisms is key for their effectiveness, by allowing
us to: define and enforce global policies for those properties; reduce the
complexity of controllers and forwarding devices; ensure higher levels of
robustness for critical services; foster interoperability of the non-functional
property enforcement mechanisms; and promote the security and resilience of the
architecture itself. We discuss design and implementation aspects, and we prove
and evaluate our algorithms and mechanisms, including the formalisation of the
main protocols and the verification of their core security properties using the
Tamarin prover.Comment: 42 pages, 4 figures, 3 tables, 5 algorithms, 139 reference
A Survey on Wireless Security: Technical Challenges, Recent Advances and Future Trends
This paper examines the security vulnerabilities and threats imposed by the
inherent open nature of wireless communications and to devise efficient defense
mechanisms for improving the wireless network security. We first summarize the
security requirements of wireless networks, including their authenticity,
confidentiality, integrity and availability issues. Next, a comprehensive
overview of security attacks encountered in wireless networks is presented in
view of the network protocol architecture, where the potential security threats
are discussed at each protocol layer. We also provide a survey of the existing
security protocols and algorithms that are adopted in the existing wireless
network standards, such as the Bluetooth, Wi-Fi, WiMAX, and the long-term
evolution (LTE) systems. Then, we discuss the state-of-the-art in
physical-layer security, which is an emerging technique of securing the open
communications environment against eavesdropping attacks at the physical layer.
We also introduce the family of various jamming attacks and their
counter-measures, including the constant jammer, intermittent jammer, reactive
jammer, adaptive jammer and intelligent jammer. Additionally, we discuss the
integration of physical-layer security into existing authentication and
cryptography mechanisms for further securing wireless networks. Finally, some
technical challenges which remain unresolved at the time of writing are
summarized and the future trends in wireless security are discussed.Comment: 36 pages. Accepted to Appear in Proceedings of the IEEE, 201
One-Time Universal Hashing Quantum Digital Signatures without Perfect Keys
Quantum digital signatures (QDS), generating correlated bit strings among
three remote parties for signatures through quantum law, can guarantee
non-repudiation, authenticity, and integrity of messages. Recently, one-time
universal hashing QDS framework, exploiting the quantum asymmetric encryption
and universal hash functions, has been proposed to significantly improve the
signature rate and ensure unconditional security by directly signing the hash
value of long messages. However, similar to quantum key distribution, this
framework utilizes keys with perfect secrecy by performing privacy
amplification that introduces cumbersome matrix operations, thereby consuming
large computational resources, causing delays and increasing failure
probability. Here, we prove that, different from private communication,
imperfect quantum keys with limited information leakage can be used for digital
signatures and authentication without compromising the security while having
eight orders of magnitude improvement on signature rate for signing a megabit
message compared with conventional single-bit schemes. This study significantly
reduces the delay for data postprocessing and is compatible with any quantum
key generation protocols. In our simulation, taking two-photon twin-field key
generation protocol as an example, QDS can be practically implemented over a
fiber distance of 650 km between the signer and receiver. For the first time,
this study offers a cryptographic application of quantum keys with imperfect
secrecy and paves a way for the practical and agile implementation of digital
signatures in a future quantum network.Comment: Comments are welcome
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