In this paper, we analyse the Transport Layer Security (TLS) protocol (in particular, bilateral TLS in public-key mode) within the strand spaces setting. In [BL03] Broadfoot and Lowe suggested an abstraction of TLS. The abstraction models the security services that appear to be provided by the protocol to the high-level security layers. The outcome of our analysis provides a formalisation of th...

In this paper, we present two extensions of the strand space method to model Kerberos V. First, we include time and timestamps to model security protocols with timestamps: we relate a key to a crack time and combine it with timestamps in order to define a notion of recency. Therefore, we can check replay attacks in this new framework. Second, we extend the classic strand space theory to model p...

Although fair exchange protocols are being widely implemented, there are few formal methods able to verify them. This work introduces the strand spaces method for verifying certified mail delivery protocols, a subclass of fair exchange protocols. Three fair exchange properties are verified: effectiveness, verifiability of TTP and timeliness. For effectiveness and verifiability we used the FPH p...

Many cryptographic protocols are intended to coordinate state changes among principals. Exchange protocols coordinate delivery of new values to the participants, e.g. additions to the set of values they possess. An exchange protocol is fair if it ensures that delivery of new values is balanced: If one participant obtains a new possession via the protocol, then all other participants will, too. ...

Formal analysis of security protocols is largely based on a set of assumptions commonly referred to asthe Dolev-Yao model. Two formalisms that state the basic assumptions of this model are related here:strand spaces and multiset rewriting with existential quantification. Strand spaces provide a simple andeconomical approach to analysis of completed protocol runs by emphasizing causa...

Formal protocol analysis tools provide objective evidence that a protocol under standardization meets security goals, as well as counterexamples to goals it does not meet (“attacks”). Different tools are however based on different execution semantics and adversary models. If different tools are applied to alternative protocols under standardization, can formal evidence offer a yardstick to comp...

A type flaw attack on a security protocol is an attack where a field in a message that was originally intended to have one type is subsequently interpreted as having another type. Heather et al. proves that type flaw attacks can be prevented with the technique of tagging each field with the information that indicates its intended type. We simplify Heather et al.’s tagging scheme by combining al...

Skeletons model partial information about regular (honest) behavior in an execution of a cryptographic protocol. A homomorphism between skeletons is an information-preserving map. Much protocol analysis may be regarded as an exploration of the properties of the category of skeletons and homomorphisms. In particular, the strand space authentication tests are special homomorphisms. These ideas su...

Preserving the original RNA orientation information in RNA-Sequencing (RNA-Seq) experiment is essential to the analysis and understanding of the complexity of mammalian transcriptomes. We describe herein a simple, robust, and time-effective protocol for generating strand-specific RNA-seq libraries suited for the Illumina sequencing platform. We modified the Illumina TruSeq RNA sample preparatio...

We report optimization of single-strand conformation polymorphism (SSCP) analysis in the presence of polyethylene glycol. The protocol developed separates single-strand conformers in a much shorter time (1-3 h) than conventional SSCP protocols and broadens the applicability of SSCP analysis from 150 to as much as 500 bp of DNA by different percentages of GC content present. We conclude that add...