Adaptive secure network model for dynamic wireless mesh network

University of Technology Sydney. Faculty of Engineering and Information Technology.We as an advanced civilization rely on communication networks for a lot of important tasks. They are used to share information between vital systems, provide us with our pin-point location, access various digital resources and to stay connected with each other. Due to its necessity and enormity, maintaining and securing such a communication medium is an important task. As most communication networks rely on centralized systems, they are bound by the control of a central entity and are unable to keep up with the current growth of the network and advancements in electronic devices. The next step in an inter-connected world requires a decentralized distributed system that can also provide high levels of security. One possible solution is a dynamic distributed wireless mesh network as it provides all the features of a traditional network along with the flexibility of wireless communication and an infrastructure less distributed setup. The network can be created by connecting mobile or stationary devices together using wireless communication devices (such as smartphones, laptops, hot-spots, etc). As the network is created by multiple devices, it would not break-down if some of the devices were disabled. On the contrary, as the network uses hopping for message transmission using dynamic routes, it can self-heal by creating alternate routes if a device was to fail. As the workings and features of a dynamic mesh network differ from the traditional network, it also requires a modified security framework that can provide high levels of security whilst taking benefit of the dynamic mesh network’s unique features. This thesis investigates the problems and limitations linked to secure dynamic wireless mesh networks and how they can be improved upon. In addition to the routing protocols used and how they can be improved upon, the thesis also elaborates on the various security concerns with such networks. As distributed networks aren’t dependent on a central entity, enabling various security features such as authentication are a major challenge. In addition to the decentralized nature of the networks, a single security scheme would not be able to cover the various types of requirements a given scenario in the network might have. Along with authentication, providing end-to-end encryption is also an important component towards ensuring the data travelling through the network is secure and not tampered with. Encryption is also essential in a dynamic wireless mesh network as the data transmitted travels through multiple devices on the network before reaching the destination node and can be easily compromised if not secured. With such an importance of encryption, the network also requires a key management and distribution framework. As traditional network uses a centralized system for maintaining and distributing cryptographic keys in the network, it is a big challenge to implement the same in a distributed network with minimal dependence on a central entity. The key exchange must consider the nature of the network and accordingly incorporate improvements to be able to function in a distributed network. This thesis explores the above areas to propose a new network model for a secure dynamic wireless mesh network including a new routing scheme and a security framework comprising a hybrid encryption scheme, a hybrid authentication scheme and an improved key exchange and management scheme. This thesis demonstrates that our solutions not only strengthen and secure the dynamic wireless mesh networks but also significantly improve the performance and efficiency as compared to existing approaches

Does Individual Performance Affect Entrepreneurial Mobility? Empirical Evidence from the Financial Analysis Market

Our paper contributes to the studies on the relationship between workers' human capital and their decision to become self-employed as well as their probability to survive as entrepreneurs. Analysis from a panel data set of research analysts in investment banks over 1988-1996 reveals that star analysts are more likely than non-star analysts to become entrepreneurs. Furthermore, we find that ventures started by star analysts have a higher probability of survival than ventures established by non-star analysts. Extending traditional theories of entrepreneurship and labor mobility, our results also suggest that drivers of turnover vary by destination: (a) turnover to entrepreneurship and (b) other turnover. In contrast to turnover to entrepreneurship, star analysts are less likely to move to other firms than non-star analysts.

A novel approach to teaching fluoroscopic neuroanatomy and spine injection skills

Learning and understanding fluoroscopic neuroanatomy and acquiring the skills to safely perform spine injections is an essential part of training for many radiology, neurology, neurosurgery, anesthesia, and physical medicine and rehabilitation residents. Unfortunately there are no inexpensive and easily accessible models available to simulate and teach this essential skill. Thus, much of the teaching and learning is done while the patient is on the fluoroscopy table using the “See one, do one, teach one” method

Hiring Teams, Firms and Lawyer: Evidence of the Evolving Relationships in the Corporate Legal Market

How are relationships between corporate clients and law firms evolving? Drawing on interview and survey data from 166 chief legal officers of S&P 500 companies from 2006–2007, we find that—contrary to standard depictions of corporate client-provider relationships—(1) large companies have relationships with ten to twenty preferred providers; (2) these relationships continue to be enduring; and (3) clients focus not only on law firm platforms and lead partners, but also on teams and departments within preferred providers, allocating work to these subunits at rival firms over time and following “star” lawyers, especially if they move as part of a team. The combination of long-term relationships and subunit rivalry provides law firms with steady work flows and allows companies to keep cost pressure on firms while preserving relationship-specific capital, quality assurance, and soft forms of legal capacity insurance. Our findings have implications for law firms, corporate departments, and law schools

Head nodding: An unusual presentation of congenital brain tumor

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Hiring Teams, Firms, and Lawyers: Evidence of the evolving Relationship in the Corporate Legal Market

How are relationships between corporate clients and law firms evolving? Drawing on interview and survey data from 166 chief legal officers of S&P 500 companies from 2006-2007, we find that-contrary to standard depictions of corporate client-provider relationships-(1) large companies have relationships with ten to twenty preferred providers; (2) these relationships continue to be enduring, and (3) clients focus not only on law firm platforms and lead partners, but also on teams and departments within preferred providers, allocating work to these subunits at rival firms over time and following star lawyers, especially if they move as part of a team. The combination of long-term relationships and subunit rivalry provides law firms with steady work flows and allows companies to keep cost pressure on firms while preserving relationship-specific capital, quality assurance, and soft forms of legal capacity insurance. Our findings have implications for law firms, corporate departments, and law schools

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Endovascular Treatment of Acute Ischemic Stroke With the Penumbra System in Routine Practice: COMPLETE Registry Results

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