Distributed Access Control with Blockchain

The specification and enforcement of network-wide policies in a single administrative domain is common in today's networks and considered as already resolved. However, this is not the case for multi-administrative domains, e.g. among different enterprises. In such situation, new problems arise that challenge classical solutions such as PKIs, which suffer from scalability and granularity concerns. In this paper, we present an extension to Group-Based Policy -- a widely used network policy language -- for the aforementioned scenario. To do so, we take advantage of a permissioned blockchain implementation (Hyperledger Fabric) to distribute access control policies in a secure and auditable manner, preserving at the same time the independence of each organization. Network administrators specify polices that are rendered into blockchain transactions. A LISP control plane (RFC 6830) allows routers performing the access control to query the blockchain for authorizations. We have implemented an end-to-end experimental prototype and evaluated it in terms of scalability and network latency.Comment: 7 pages, 9 figures, 2 table

Decentralized trust in the inter-domain routing infrastructure

Inter-domain routing security is of critical importance to the Internet since it prevents unwanted traffic redirections. The current system is based on a Public Key Infrastructure (PKI), a centralized repository of digital certificates. However, the inherent centralization of such design creates tensions between its participants and hinders its deployment. In addition, some technical drawbacks of PKIs delay widespread adoption. In this paper we present IPchain, a blockchain to store the allocations and delegations of IP addresses. IPchain leverages blockchains' properties to decentralize trust among its participants, with the final goal of providing flexible trust models that adapt better to the ever-changing geopolitical landscape. Moreover, we argue that Proof of Stake is a suitable consensus algorithm for IPchain due to the unique incentive structure of this use-case, and that blockchains offer relevant technical advantages when compared to existing systems, such as simplified management. In order to show its feasibility and suitability, we have implemented and evaluated IPchain's performance and scalability storing around 350k IP prefixes in a 2.5 GB chain.Peer ReviewedPostprint (published version

FASTING ENHANCES TKI EFFICACY ON THYROID CANCER CELLS

Tyrosine kinase inhibitors (TKIs) have emerged as a novel cancer therapy for patients with poorly differentiated, anaplastic or medullary carcinomas unresponsive to conventional treatments. The association between fasting mimicking diets and TKIs has been explored with encouraging results showing a better response with less side effects due to TKI toxicity. Here we report the role of fasting in reducing cell survival and in potentiating the anticancer activity of TKIs (Lenvatinib, Sorafenib, Vandetanib and Cabozatinib) in cultured medullary, follicular, papillary and anaplastic thyroid cancer cells. In particular, fast mimicking diet reduced cell growth in all cell types but potentiated the anticancer activity of TKIs only in follicular, medullary and TPC1 thyroid cells. TKIs significantly reduced ERK1-2 activation after 1 h in all cell types. Prolonged exposure to TKIs resulted in an improvement of ERK1-2 phosphorylation which was inhibited in the presence of starvation. We demonstrated thyroid cancer cell susceptibility to fasting and validated its role in potentiating anticancer activity of TKIs by strengthening ERK1/2 signalling inhibition

Global state, local decisions: Decentralized NFV for ISPs via enhanced SDN

The network functions virtualization paradigm is rapidly gaining interest among Internet service providers. However, the transition to this paradigm on ISP networks comes with a unique set of challenges: legacy equipment already in place, heterogeneous traffic from multiple clients, and very large scalability requirements. In this article we thoroughly analyze such challenges and discuss NFV design guidelines that address them efficiently. Particularly, we show that a decentralization of NFV control while maintaining global state improves scalability, offers better per-flow decisions and simplifies the implementation of virtual network functions. Building on top of such principles, we propose a partially decentralized NFV architecture enabled via an enhanced software-defined networking infrastructure. We also perform a qualitative analysis of the architecture to identify advantages and challenges. Finally, we determine the bottleneck component, based on the qualitative analysis, which we implement and benchmark in order to assess the feasibility of the architecture.Peer ReviewedPostprint (author's final draft

Monitoraggio del nodulo tiroideo benigno in accordo con la classe di rischio ecografica

L’ecografia è il principale strumento diagnostico nell’ambito della patologia nodulare tiroidea. Negli ultimi anni si sono susseguite diverse linee guida finalizzate a standardizzare la descrizione ecografica e a modulare la gestione del nodulo tiroideo sulla base delle caratteristiche ecografiche. Tra le più utilizzate a livello internazionale vi sono quelle dell’American Association of Clinical Endocrinologists/American College of Endocrinology/Associazione Medici Endocrinologi (AACE/ACE/AME) [1], le linee guida 2015 dell’American Thyroid Association (ATA) [2], le linee guida della European Thyroid Association (ETA) (European Thyroid Imaging Reporting and Data System) [3] e l’American College of Radiology (ACR) TIRADS [4]. L’obiettivo primario di queste linee guida è quello di identificare, sulla base delle caratteristiche ecografiche, i noduli a maggior rischio di malignità da sottoporre ad agoaspirato (FNAC) e di ridurre il numero di agoaspirazioni tiroidee non necessarie, senza tuttavia aumentare il numero di mancate diagnosi di cancro tiroideo. La definizione del rischio ecografico del nodulo è inoltre utilizzata per modulare il follow-up a breve e a lungo termine dei noduli tiroidei citologicamente o ecograficamente benigni [4]

EIF1AX c.338-2A>T splice site mutation in a patient with trabecular adenoma and cytological indeterminate lesion

SUMMARY The EIF1AX gene mutations have been recently associated with papillary thyroid carcinoma and anaplastic thyroid cancer. According with these reports, the gene as been considered as a drive gene for thyroid cancer development. However, the occurrence of these alterations in benign thyroid lesions is not known and is still under investigation. Some authors have already reported the presence of EIF1AX variants in follicular adenomas and hyperplastic nodules. Here, we describe for the first time a case of a man with the EIF1AX c.338-2A>T splice site mutation in an indeterminate FNA lesion with trabecular adenoma at final histology in the absence of other pathogenetic mutations, demonstrating that further studies are required to better understand EIF1AX role in the tumorigenesis of thyroid carcinoma

Beta-agonist stimulation ameliorates the phenotype of spinal and bulbar muscular atrophy mice and patient-derived myotubes

Spinal and bulbar muscular atrophy (SBMA) is a neuromuscular disease characterized by the loss of lower motor neurons. SBMA is caused by expansions of a polyglutamine tract in the gene coding for androgen receptor (AR). Expression of polyglutamine-expanded AR causes damage to motor neurons and skeletal muscle cells. Here we investigated the effect of β-agonist stimulation in SBMA myotube cells derived from mice and patients, and in knock-in mice. We show that treatment of myotubes expressing polyglutamine-expanded AR with the β-agonist clenbuterol increases their size. Clenbuterol activated the phosphatidylinositol-3-kinase (PI3K)/Akt/mechanistic target of rapamycin (mTOR) pathway and decreased the accumulation of polyglutamine-expanded AR. Treatment of SBMA knock-in mice with clenbuterol, which was started at disease onset, ameliorated motor function and extended survival. Clenbuterol improved muscle pathology, attenuated the glycolytic-to-oxidative metabolic alterations occurring in SBMA muscles and induced hypertrophy of both glycolytic and oxidative fibers. These results indicate that β-agonist stimulation is a novel therapeutic strategy for SBMA

SEMPER: a stateless traffic engineering solution for WAN based on MP-TCP

Proceeding of: IEEE International Conference on Communications (ICC 2018)Enterprise Networking has a strong set of requirements in terms of resiliency, reliability and resources usage. With current approaches being based on monolithic and expensive infrastructures using dedicated overlay links, providers are moving to more economical hybrid solutions that encompass private dedicated links with public/regular Internet connections. However, these usually rely on complex, hardware-dependent and/or proprietary Traffic Engineering (TE) solutions, which are computationally costly, in particular for the forwarding nodes. In this paper, we propose SEMPER: a lightweight TE solution based on MP-TCP that, in contrast to other TE solutions, moves the complexity to the endpoints of the connection, and relieves the forwarding elements from complex operations or even maintaining state. As our evaluation shows, SEMPER efficiently makes use of all available paths between the endpoints while maintaining fairness, and properly adapts to variations on the available capacity.This work has been partly supported by the H2020 5GMoNArch project (grant agreement 761445), and by the Madrid Regional Government through the TIGRE5-CM program (S2013/ICE-2919)