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See detailA Protocol to Strengthen Password-Based Authentication
Vazquez Sandoval, Itzel UL; Lenzini, Gabriele UL; Stojkovski, Borce UL

in Emerging Technologies for Authorization and Authentication (2018, November)

We discuss a password-based authentication protocol that we argue to be robust against password-guessing and o -line dictionary attacks. The core idea is to hash the passwords with a seed that comes from ... [more ▼]

We discuss a password-based authentication protocol that we argue to be robust against password-guessing and o -line dictionary attacks. The core idea is to hash the passwords with a seed that comes from an OTP device, making the resulting identity token unpredictable for an adversary. We believe that the usability of this new protocol is the same as that of password-based methods with OTP, but has the advan- tage of not burdening users with having to choose strong passwords. [less ▲]

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See detailUn protocole de sauvegarde / reprise coordonné pour les applications à flot de données reconfigurables
Besseron, Xavier UL; Pigeon, Laurent; Gautier, Thierry et al

in Technique et Science Informatiques (2007)

Detailed reference viewed: 66 (2 UL)
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See detailProtocols and programs for high-throughput growth and aging phenotyping in yeast.
Jung, Paul UL; Christian, Nils UL; Kay, Daniel UL et al

in PloS one (2015), 10(3), 0119807

In microorganisms, and more particularly in yeasts, a standard phenotyping approach consists in the analysis of fitness by growth rate determination in different conditions. One growth assay that combines ... [more ▼]

In microorganisms, and more particularly in yeasts, a standard phenotyping approach consists in the analysis of fitness by growth rate determination in different conditions. One growth assay that combines high throughput with high resolution involves the generation of growth curves from 96-well plate microcultivations in thermostated and shaking plate readers. To push the throughput of this method to the next level, we have adapted it in this study to the use of 384-well plates. The values of the extracted growth parameters (lag time, doubling time and yield of biomass) correlated well between experiments carried out in 384-well plates as compared to 96-well plates or batch cultures, validating the higher-throughput approach for phenotypic screens. The method is not restricted to the use of the budding yeast Saccharomyces cerevisiae, as shown by consistent results for other species selected from the Hemiascomycete class. Furthermore, we used the 384-well plate microcultivations to develop and validate a higher-throughput assay for yeast Chronological Life Span (CLS), a parameter that is still commonly determined by a cumbersome method based on counting "Colony Forming Units". To accelerate analysis of the large datasets generated by the described growth and aging assays, we developed the freely available software tools GATHODE and CATHODE. These tools allow for semi-automatic determination of growth parameters and CLS behavior from typical plate reader output files. The described protocols and programs will increase the time- and cost-efficiency of a number of yeast-based systems genetics experiments as well as various types of screens. [less ▲]

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See detailProtocols and Stability Analysis for Energy Harvesting TDMA Systems with/without Relaying
Ottersten, Björn UL; Krikidis, Ioannis; Zheng, Gan UL

in IEEE Global Telecommunications Conference (GLOBECOM) (2013, December)

Detailed reference viewed: 131 (2 UL)
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See detailPROTOGIM: a novel tool to search motifs and domains in hypothetical proteins of protozoan genomes.
Cestari, Igor S.; Haver, Nicolaas J.; Barbosa Da Silva, Adriano UL et al

in Parasitology research (2006), 98(4), 375-7

Whole sequencing of protozoan trypanosomatid genomes revealed the presence of several predicted unknown genes coding for hypothetical proteins. Pairwise, alignment-based, computational methods available ... [more ▼]

Whole sequencing of protozoan trypanosomatid genomes revealed the presence of several predicted unknown genes coding for hypothetical proteins. Pairwise, alignment-based, computational methods available online are unable to identify the function of these sequences. To detect clues to identify the function of hypothetical proteins, a user-friendly, bioinformatic tool named PROTOzoan Gene Identification Motifs (PROTOGIM, available on http://www.biowebdb.org/protogim ) was developed, which allows the user to search functional patterns of hypothetical proteins through the screening of regular expression in the sequences. The analysis of 1,194 trypanosomatid hypothetical proteins through PROTOGIM resulted in an identification of motifs and domains in 98% of the cases, demonstrating the reliability and accuracy of the employed method. The added value of this tool is the possibility to modify or insert new regular expressions to perform an analysis against either one or several sequences at the same time. An in silico strategy along with biochemical and molecular characterizations creates new possibilities to find the functions of hypothetical proteins at the postgenome era. [less ▲]

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See detailProtons selectively induce lasting excitation and sensitization to mechanical stumulation of nociceptors in rat skin, in vitro
Steen, Kai h; Reeh, Peter-Werner; Anton, Fernand UL et al

in Journal of Neuroscience (1992), 12(1), 86-95

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See detailPrototype Incorporated Emotional Neural Network (PI-EmNN)
Oyedotun, Oyebade UL; Khashman, Adnan

in IEEE Transactions on Neural Networks and Learning Systems (2017)

Artificial neural networks (ANNs) aim to simulate the biological neural activities. Interestingly, many ‘engineering’ prospects in ANN have relied on motivations from cognition and psychology studies. So ... [more ▼]

Artificial neural networks (ANNs) aim to simulate the biological neural activities. Interestingly, many ‘engineering’ prospects in ANN have relied on motivations from cognition and psychology studies. So far, two important learning theories that have been subject of active research are the prototype and adaptive learning theories. The learning rules employed for ANNs can be related to adaptive learning theory, where several examples of the different classes in a task are supplied to the network for adjusting internal parameters. Conversely, prototype learning theory uses prototypes (representative examples); usually, one prototype per class of the different classes contained in the task. These prototypes are supplied for systematic matching with new examples so that class association can be achieved. In this paper, we propose and implement a novel neural network algorithm based on modifying the emotional neural network (EmNN) model to unify the prototype and adaptive learning theories. We refer to our new model as “PI-EmNN” (Prototype-Incorporated Emotional Neural Network). Furthermore, we apply the proposed model to two real-life challenging tasks, namely; static hand gesture recognition and face recognition, and compare the result to those obtained using the popular back propagation neural network (BPNN), emotional back propagation neural network (EmNN), deep networks and an exemplar classification model, k-nearest neighbor (k-NN). [less ▲]

Detailed reference viewed: 91 (17 UL)
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See detailProva scientifica e dimensione europea
Allegrezza, Silvia UL

in Canzio, Giovanni; Luparia, Luca (Eds.) Prova scientifica e processo penale (2018)

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See detailPROVABLE SECURITY ANALYSIS FOR THE PASSWORD AUTHENTICATED KEY EXCHANGE PROBLEM
Lopez Becerra, José Miguel UL

Doctoral thesis (2019)

Password-based Authenticated Key-Exchange (PAKE) protocols allow the establishment of secure communications despite a human-memorable password being the only secret that is previously shared between the ... [more ▼]

Password-based Authenticated Key-Exchange (PAKE) protocols allow the establishment of secure communications despite a human-memorable password being the only secret that is previously shared between the participants. After more than 25 years since the initial proposal, the PAKE problem remains an active area of research, probably due to the vast amount of passwords deployed on the internet as password-based still constitutes the most extensively used method for user authentication. In this thesis, we consider the computational complexity approach to improve the current understanding of the security provided by previously proposed PAKE protocols and their corresponding security models. We expect that this work contributes to the standardization, adoption and more efficient implementation of the considered protocols. Our first contribution is concerning forward secrecy for the SPAKE2 protocol of Abdalla and Pointcheval (CT-RSA 2005). We prove that the SPAKE2 protocol satisfies the so-called notion of weak forward secrecy. Furthermore, we demonstrate that the incorporation of key-confirmation codes in the original SPAKE2 results in a protocol that provably satisfies the stronger notion of perfect forward secrecy. As forward secrecy is an explicit requirement for cipher suites supported in the TLS handshake, we believe our results fill the gap in the literature and facilitate the adoption of SPAKE2 in the recently approved TLS 1.3. Our second contribution is regarding tight security reductions for EKE-based protocols. We present a security reduction for the PAK protocol instantiated over Gap Diffie-Hellman groups that is tighter than previously known reductions. We discuss the implications of our results for concrete security. Our proof is the first to show that the PAK protocol can provide meaningful security guarantees for values of the parameters typical in today's world. Finally, we study the relation between two well-known security models for PAKE protocols. Security models for PAKEs aim to capture the desired security properties that such protocols must satisfy when executed in the presence of an adversary. They are usually classified into i) indistinguishability-based (IND-based) or ii) simulation-based (SIM-based), however, controversy remains within the research community regarding what is the most appropriate security model that better reflects the capabilities that an adversary is supposed to have in real-world scenarios. Furthermore, the relation between these two security notions is unclear and mentioned as a gap in the literature. We prove that SIM-BMP security from Boyko et al. (EUROCRYPT 2000) implies IND-RoR security from Abdalla et al. (PKC 2005) and that IND-RoR security is equivalent to a slightly modified version of SIM-BMP security. We also investigate whether IND-RoR security implies (unmodified) SIM-BMP security. [less ▲]

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See detailProvable Security and Indifferentiability
Mandal, Avradip UL

Doctoral thesis (2012)

In this thesis we consider different problems related to provable security and indifferentiability framework. Ideal primitives such as random oracles, ideal ciphers are theoretical abstractions of ... [more ▼]

In this thesis we consider different problems related to provable security and indifferentiability framework. Ideal primitives such as random oracles, ideal ciphers are theoretical abstractions of cryptographic hash functions and block ciphers respectively. These idealized models help us to argue security guarantee for various cryptographic schemes, for which standard model security proofs are not known. In the first part of this thesis we consider the problems related to ideal primitive construction starting from a different ideal primitive. We adopt the indifferentiability framework proposed by Maurer et. al. in TCC’04 for this purpose. The indifferentiability framework helps us to preserve the security guarantee of cryptographic schemes when the ideal primitives are replaced by indifferentiable constructions, even when the ideal primitives are used in a public manner. At first, we consider the problem of ideal cipher domain extension. We show the 3-round Feistel construction, built using n-bit ideal ciphers are actually indifferentiable from a 2n-bit ideal cipher. We also consider other related issues such as, why 2-round Feistel is not sufficient, security analysis in standard indistinguishability model for both 2 and 3 round constructions, etc. Afterwards, we consider the open problem: whether 6-round Feistel construction using random round functions is indifferentiable from a random invertible permutation or not. We give a partial positive answer to this question. We show the construction is actually publicly-indifferentiable (which is a restricted version of full indifferentiability) from an in- vertible random permutation. In the later part of the thesis, we concentrate on some issues related to the security of Probabilistic Signature Scheme (PSS). PSS with RSA trapdoor is a widely deployed randomized signature scheme. It is known to be secure in Random Oracle model. However, recently randomized signature scheme such as iso/iec 9796-2 is shown to be susceptible to hardware fault attacks. In this work we show, PSS is actually secure against random fault attacks in random oracle model. Afterwards, we consider the openproblem related to standard model security of PSS. We give a general negative result in this direction. We rule out existence of any black box proof technique showing security of PSS in standard model. [less ▲]

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See detailProvable Security of (Tweakable) Block Ciphers Based on Substitution-Permutation Networks
Cogliati, Benoît-Michel UL; Dodis, Yevgeniy; Katz, Jonathan et al

in Provable Security of (Tweakable) Block Ciphers Based on Substitution-Permutation Networks (2018)

Substitution-Permutation Networks (SPNs) refer to a family of constructions which build a wn-bit block cipher from n-bit public permutations (often called S-boxes), which alternate keyless and “local” ... [more ▼]

Substitution-Permutation Networks (SPNs) refer to a family of constructions which build a wn-bit block cipher from n-bit public permutations (often called S-boxes), which alternate keyless and “local” substitution steps utilizing such S-boxes, with keyed and “global” permu- tation steps which are non-cryptographic. Many widely deployed block ciphers are constructed based on the SPNs, but there are essentially no provable-security results about SPNs. In this work, we initiate a comprehensive study of the provable security of SPNs as (possibly tweakable) wn-bit block ciphers, when the underlying n-bit permutation is modeled as a public random permutation. When the permutation step is linear (which is the case for most existing designs), we show that 3 SPN rounds are necessary and sufficient for security. On the other hand, even 1-round SPNs can be secure when non-linearity is allowed. Moreover, 2-round non-linear SPNs can achieve “beyond- birthday” (up to 2 2n/3 adversarial queries) security, and, as the number of non-linear rounds increases, our bounds are meaningful for the number of queries approaching 2 n . Finally, our non-linear SPNs can be made tweakable by incorporating the tweak into the permutation layer, and provide good multi-user security. As an application, our construction can turn two public n-bit permuta- tions (or fixed-key block ciphers) into a tweakable block cipher working on wn-bit inputs, 6n-bit key and an n-bit tweak (for any w ≥ 2); the tweakable block cipher provides security up to 2 2n/3 adversarial queries in the random permutation model, while only requiring w calls to each permutation, and 3w field multiplications for each wn-bit input. [less ▲]

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See detailProvably Secure Countermeasures against Side-channel Attacks
Vadnala, Praveen Kumar UL

Doctoral thesis (2015)

Side-channel attacks exploit the fact that the implementations of cryptographic algorithms leak information about the secret key. In power analysis attacks, the observable leakage is the power consumption ... [more ▼]

Side-channel attacks exploit the fact that the implementations of cryptographic algorithms leak information about the secret key. In power analysis attacks, the observable leakage is the power consumption of the device, which is dependent on the processed data and the performed operations.\ignore{While Simple Power Analysis (SPA) attacks try to recover the secret value by directly interpreting the power measurements with the corresponding operations, Differential Power Analysis (DPA) attacks are more sophisticated and aim to recover the secret value by applying statistical techniques on multiple measurements from the same operation.} Masking is a widely used countermeasure to thwart the powerful Differential Power Analysis (DPA) attacks. It uses random variables called masks to reduce the correlation between the secret key and the obtained leakage. The advantage with masking countermeasure is that one can formally prove its security under reasonable assumptions on the device leakage model. This thesis proposes several new masking schemes along with the analysis and improvement of few existing masking schemes. The first part of the thesis addresses the problem of converting between Boolean and arithmetic masking. To protect a cryptographic algorithm which contains a mixture of Boolean and arithmetic operations, one uses both Boolean and arithmetic masking. Consequently, these masks need to be converted between the two forms based on the sequence of operations. The existing conversion schemes are secure against first-order DPA attacks only. This thesis proposes first solution to switch between Boolean and arithmetic masking that is secure against attacks of any order. Secondly, new solutions are proposed for first-order secure conversion with logarithmic complexity (${\cal O}(\log k)$ for $k$-bit operands) compared to the existing solutions with linear complexity (${\cal O}(k)$). It is shown that this new technique also improves the complexity of the higher-order conversion algorithms from ${\cal O}(n^2 k)$ to ${\cal O}(n^2 \log k)$ secure against attacks of order $d$, where $n = 2d+1$. Thirdly, for the special case of second-order masking, the running times of the algorithms are further improved by employing lookup tables. The second part of the thesis analyzes the security of two existing Boolean masking schemes. Firstly, it is shown that a higher-order masking scheme claimed to be secure against attacks of order $d$ can be broken with an attack of order $d/2+1$. An improved scheme is proposed to fix the flaw. Secondly, a new issue concerning the problem of converting the security proofs from one leakage model to another is examined. It is shown that a second-order masking scheme secure in the Hamming weight model can be broken with a first-order attack on a device leaking in the Hamming distance model. This result underlines the importance of re-evaluating the security proofs for devices leaking in different models. [less ▲]

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See detailProvably Secure Single Sign-on Scheme in Distributed Systems and Networks
Yu, Jiangshan UL; Wang, Guilin; Mu, Yi

in 11th IEEE International Conference on Trust, Security and Privacy in Computing and Communications, TrustCom 2012, Liverpool, United Kingdom, June 25-27, 2012 (2012)

Detailed reference viewed: 123 (0 UL)
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See detailLe provençal / L'occitan
Weth, Constanze UL

in Klump, André; Kramer, Johannes; Willems, Aline (Eds.) Manuel des langues romanes (2014)

L’article donne un aperçu du statut, de l’élaboration et des usages de l’occitan au cours de l’histoire et dans les différents domaines sociaux. Il commence par une brève qualification de l’occitan. Puis ... [more ▼]

L’article donne un aperçu du statut, de l’élaboration et des usages de l’occitan au cours de l’histoire et dans les différents domaines sociaux. Il commence par une brève qualification de l’occitan. Puis il traite de l’élaboration et de la codification de ce dernier. Cet aspect recouvre l’expansion de l’occitan au début du dernier millénaire, l’infiltration du français et les efforts faits pour parvenir à une élaboration et une standardisation de l’occitan dès la fin du XIXe siècle. La partie suivante résume les différentes époques littéraires depuis l’an 1000. La prochaine section traite de l’occitan à l’école. Elle montre le rôle joué par l’école française dans le déclin de l’occitan, mais révèle néanmoins ses acquis depuis le XXe siècle. Par la suite, on fait état des usages de l’occitan au XXIe siècle. Le dernier paragraphe est dédié à la sociolinguistique occitane du XXe siècle. Celle-ci a ouvert un vaste champ de recherche sur l’occitan et a abouti à une reprise de conscience non négligeable à propos de la langue et de la culture occitanes. [less ▲]

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See detailProving Prêt à Voter Receipt Free Using Computational Security Models
Khader, Dalia UL; Ryan, Peter UL; Tang, Qiang UL

in USENIX Journal of Election Technology and Systems (2013), 1(1), 62-81

Pret a Voter is a supervised, end-to-end verifiable voting scheme. Informal analyses indicate that, subject to certain assumptions, Pret a Voter is receipt free, i.e. a voter has no way to construct a ... [more ▼]

Pret a Voter is a supervised, end-to-end verifiable voting scheme. Informal analyses indicate that, subject to certain assumptions, Pret a Voter is receipt free, i.e. a voter has no way to construct a proof to a coercer of how she voted. In this paper we propose a variant of Pret a Voter and prove receipt freeness of this scheme using computational methods. Our proof shows that if there exists an adversary that breaks receipt freeness of the scheme then there exists an adversary that breaks the IND-CCA2 security of the Naor-Yung encryption scheme. We propose a security model that defines receipt freeness based on the indistinguishability of receipts. We show that in order to simulate the game we require an IND-CCA2 encryption scheme to create the ballots and receipts. We show that, within our model, a non-malleable onion is sufficient to guarantee receipt freeness. Most of the existing Pret a Voter schemes do not employ IND-CCA2 encryption in the construction of the ballots, but they avoid such attacks by various additional mechanisms such as pre-commitment of ballot material to the bulletin board, digitally signed ballots etc. Our use of the Naor-Yung transformation provides the IND-CCA2 security required. [less ▲]

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See detailProving Regulatory Compliance: Business Processes, Logic, Complexity
Colombo Tosatto, Silvano UL

Doctoral thesis (2015)

The problem of proving regulatory compliance of a business process model is composed of two main elements. One of these elements is the business process model, which provides a formal compact description ... [more ▼]

The problem of proving regulatory compliance of a business process model is composed of two main elements. One of these elements is the business process model, which provides a formal compact description of the available executions capable of achieving a given business objective. The other element is the regulatory framework that the business process must follow, describing the compliance requirements given by the law or by a company’s own internal regulations. The problem consists of verifying whether a given business process model is compliant with the regulatory framework, which is carried out by verifying whether the executions of the model comply with the requirements of the regulatory framework. Solutions to prove the regulatory compliance of business processes have been already proposed in the past. Some solutions disregard the computational complexity aspect of the problem, while other solutions either solve a simplified version of the problem efficiently or provide approximate solutions for the general one. However, none of these solutions have formally studied the computational complexity of the problem of proving regulatory compliance. This thesis addresses that issue, showing in addition why efficient solutions of the general problem are not possible. In particular I study the computational complexity of a problem of proving regulatory compliance whose regulatory framework is defined using conditional obligations. The approach I adopt to represent the compliance requirement is semantically similar to some of the existing solutions proposed by other researchers, such as van der Aalst and many others, who adopts linear temporal logic over finite traces, or different variants of such temporal logic, to define the compliance requirements. More precisely, the approach used in the present thesis adopts propositional logic as base logic, and defines the semantics of the regulatory framework in a similar way as Process Compliance Logic introduced by Governatori and Rotolo. The study of the computational complexity of the problem is approached by dividing it in sub-classes and then combining their analysis to obtain the result for the target problem. The division is done according to three features of the regulatory framework. These features define whether the framework is composed of a single or a set of obligations, whether the obligations are conditional and whether violations can be compensated. These features can be omitted to identify simpler sub-classes of the problem. After having identified the different sub-classes of the problem, I study the computational complexity of some of these sub-classes and combine the results obtained to identify the computational complexity of the general problem tackled in the present thesis, where each of the three features identified are used to describe the compliance requirements. The results of the computational complexity analysis show that proving the existence of an execution of a business process compliant with the regulatory framework is an NP-complete problem. Differently proving that for all of the executions of a business process model, they are either compliant or not with the regulatory framework, is a coNP-complete problem. The results show that combining the two elements composing the problem of proving regulatory compliance, the process model and the regulatory framework, which are tractable when considered individually, leads to an intractable problem. In addition to the computational complexity results, the analysis provided in the thesis has also shown that tractable sub-classes of the problem, where the computational complexity is at most polynomial with respect to the size of the input, can be obtained by trivialising the expressivity of either one of the elements composing the problem. However the expressivity of these sub-classes is limited. Thus I identify a different tractable sub-class of the problem by weakening the expressivity of both elements composing the problem, but where each element is not trivialised as for the other sub-classes. Whether the sub-class identified can be considered expressive is arguable, however it represents a first step towards identifying a sub-class of the problem being both tractable and expressive, taking into account the limitation of employing propositional logic as base logic. [less ▲]

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See detailDie Provinz im Zeitalter der Globalität. Romane von Peter Kurzeck (“Vorabend”), Andreas Maier (“Das Zimmer”) und Stephan Thome (“Grenzgang”).
Amann, Wilhelm UL

in Cescutti, Marjan (Ed.) Raum – Region – Kultur. Literaturgeschichtsschreibung im Kontext aktueller Diskurse. (2013)

Detailed reference viewed: 117 (3 UL)
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See detailThe provision of long-term credit and firm growth
Leon, Florian UL

E-print/Working paper (2019)

This paper investigates whether a higher level of long-term credit provision affects the growth of small and young firms. Firm-level data from more than 20,000 firms in 62 countries are combined with a ... [more ▼]

This paper investigates whether a higher level of long-term credit provision affects the growth of small and young firms. Firm-level data from more than 20,000 firms in 62 countries are combined with a new hand-collected database on short-term and long-term credit provided to the private sector. Using a difference-in-difference framework, our results indicate that, contrary to short-term credit, long-term credit does not stimulate growth of small and young firms. This finding is, at least partially, explained by the differential impact of short-term and long-term credit provision on small and young firms’ access to credit. While the provision of short-term credit alleviates credit constraints faced by small and young firms, a larger provision of longterm bank loans has an opposite impact. Our findings are in line with the hypothesis that an increase of long-term credit provision reflects a lender’s choice to provide more financing to existing clients (intensive margin) to the detriment of firms without previous access to finance (extensive margin). [less ▲]

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See detailThe provision of urban green space and its accessibility: Spatial data effects in Brussels
Le Texier, Marion UL; Schiel, Kerry UL; Caruso, Geoffrey UL

in PLoS ONE (2018), 13(10), 0204684

Urban green space (UGS) has many environmental and social benefits. UGS provision and access are increasingly considered in urban policies and must rely on data and indicators that can capture variations ... [more ▼]

Urban green space (UGS) has many environmental and social benefits. UGS provision and access are increasingly considered in urban policies and must rely on data and indicators that can capture variations in the distribution of UGS within cities. There is no consensus about how UGS, and their provision and access, must be defined from different land use data types. Here we identify four spatial dimensions of UGS and critically examine how different data sources affect these dimensions and our understanding of their variation within a city region (Brussels). We compare UGS indicators measured from an imagery source (NDVI from Landsat), an official cadastre-based map, and the voluntary geographical information provided by OpenStreetMap (OSM). We compare aggregate values of provision and access to UGS as well as their spatial distribution along a centrality gradient and at neighbourhood scale. We find that there are strong differences in the value of indicators when using the different datasets, especially due to their ability to capture private and public green space. However we find that the interpretation of intra-urban spatial variations is not affected by changes in data source. Centrality in particular is a strong determinant of the relative values of UGS availability, fragmentation and accessibility, irrespective of datasets. [less ▲]

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See detailProvisional Application of EU Trade and Investment Agreements: A Pragmatic Solution to Mixity Issues
Gatti, Mauro UL

in Fach Gómez (Ed.) La política de la Unión Europea en materia de derecho de las inversiones internacionales (2017)

Because of its limited competences, the EU often concludes trade and investment agreements in the “mixed” form, which implies long and uncertain ratification procedures. This paper suggests that the Union ... [more ▼]

Because of its limited competences, the EU often concludes trade and investment agreements in the “mixed” form, which implies long and uncertain ratification procedures. This paper suggests that the Union may bypass some of the problems created by “mixed” procedures by giving provisional application to trade and investment agreements. The analysis demonstrates that a provisionally applied agreement produces legal effects, and may therefore ensure a certain degree of legal certainty. Secondly, it is submitted that the provisional application of EU trade and investment agreements covers a large part of their substantive scope. Finally, it is contended that provisional application ensures a rather stable legal framework, because only the Union (and not its Member States) can decide to terminate it. Provisional application thus appears as a pragmatic instrument, that enables the Union to swiftly bring trade and investment agreements into application, and consequently enhances the effectiveness of the EU’s external policy. [less ▲]

Detailed reference viewed: 132 (10 UL)