Mobile user authentication system (MUAS) for e-commerce applications.

The rapid growth of e-commerce has many associated security concerns. Thus, several studies to develop secure online authentication systems have emerged. Most studies begin with the premise that the intermediate network is the primary point of compromise. In this thesis, we assume that the point of compromise lies within the end-host or browser; this security threat is called the man-in-the-browser (MITB) attack. MITB attacks can bypass security measures of public key infrastructures (PKI), as well as encryption mechanisms for secure socket layers and transport layer security (SSL/TLS) protocol. This thesis focuses on developing a system that can circumvent MITB attacks using a two-phase secure-user authentication system, with phases that include challenge and response generation. The proposed system represents the first step in conducting an online business transaction.The proposed authentication system design contributes to protect the confidentiality of the initiating client by requesting minimal and non-confidential information to bypass the MITB attack and transition the authentication mechanism from the infected browser to a mobile-based system via a challenge/response mechanism. The challenge and response generation process depends on validating the submitted information and ensuring the mobile phone legitimacy. Both phases within the MUAS context mitigate the denial-of-service (DOS) attack via registration information, which includes the client’s mobile number and the International Mobile Equipment Identity (IMEI) of the client’s mobile phone.This novel authentication scheme circumvents the MITB attack by utilising the legitimate client’s personal mobile phone as a detached platform to generate the challenge response and conduct business transactions. Although the MITB attacker may have taken over the challenge generation phase by failing to satisfy the required security properties, the response generation phase generates a secure response from the registered legitimate mobile phone by employing security attributes from both phases. Thus, the detached challenge- and response generation phases are logically linked

Targeting of β-Arrestin2 to the Centrosome and Primary Cilium: Role in Cell Proliferation Control

International audienceBackground: The primary cilium is a sensory organelle generated from the centrosome in quiescent cells and found at the surface of most cell types, from where it controls important physiological processes. Specific sets of membrane proteins involved in sensing the extracellular milieu are concentrated within cilia, including G protein coupled receptors (GPCRs). Most GPCRs are regulated by b-arrestins, barr1 and barr2, which control both their signalling and endocytosis, suggesting that barrs may also function at primary cilium.Methodology/Principal Findings: In cycling cells, βarr2 was observed at the centrosome, at the proximal region of the centrioles, in a microtubule independent manner. However, βarr2 did not appear to be involved in classical centrosome-associated functions. In quiescent cells, both in vitro and in vivo, βarr2 was found at the basal body and axoneme of primary cilia. Interestingly, βarr2 was found to interact and colocalize with 14-3-3 proteins and Kif3A, two proteins known to be involved in ciliogenesis and intraciliary transport. In addition, as suggested for other centrosome or cilia-associated proteins, βarrs appear to control cell cycle progression. Indeed, cells lacking βarr2 were unable to properly respond to serum starvation and formed less primary cilia in these conditions.Conclusions/Significance: Our results show that βarr2 is localized to the centrosome in cycling cells and to the primary cilium in quiescent cells, a feature shared with other proteins known to be involved in ciliogenesis or primary cilium function. Within cilia, βarr2 may participate in the signaling of cilia-associated GPCRs and, therefore, in the sensory functions of this cell “antenna”