Sharif Digital Repository

By definition, Mobile Clouds are networks of mobile nodes, which are connected together using short-range communication links, and at the same time keep their connection with the long-range cellular networks. Short-range communication links in Mobile Clouds provide the opportunity of Resource Sharing, which can result in new services for end-users. These services are beyond the boundaries of traditional networks.
In the following report, we aim at focusing on some problems related to Mobile Clouds. First, we present a centralized model for managing the mobility of the nodes; then we try to propose algorithms for efficient data update and processing; and finally, we introduce a novel... 

IEEE802.16 protocol is being developed and 802.16 modems will be used in every house to connect to the Internet through base-stations in both urban and rural areas. Since user bandwidth for connection to the Internet is limited, a large fraction of each modem’s bandwidth is not used. In this thesis, we propose an architecture to make a PPMN (Public Peer-to-peer Mesh Network) of all users in a city. Users can be wired or wireless under any authority. They have to forward intra-city traffic themselves. As a result, it is not required to transfer intra-city traffic through BSs except for critical information. The architecture is composed of a routing algorithm, a forwarding incentive... 

Since robustness of peer-to-peer networks depends heavily on voluntary resource sharing among individual peers, the intrinsic problem of free riding exists among autonomous rational peers that consume resources of others without contributing anything in return. One solution to the free riding problem in peer to peer networks is to have incentive mechanisms that aim to improve network efficiency by encouraging peers to cooperate. In this project, we have proposed a hybrid double-auction-based incentive mechanism for centralized peer-to-peer file sharing systems. In addition, a cryptography-based trust management scheme has been proposed to prevent peers from sending fake data. We have... 

Mobile Clouds are networks of devices with short-range communication capability, which at the same time can establish connection with the long-range cellular networks. Short-range communication links in mobile clouds provide the opportunity of resource sharing, which can result in new services for users. In this work, we study two key problems required to be addressed before the real implementation of resource sharing in mobile clouds; how to find the services offered in such clouds, and how to create incentive in users to share their resources for others.The goal of this work is to present a management framework for mobile clouds. Considering incentives in the form of price-based systems,... 

this research aims to identify interests, goals, and structures which involve privatization. The importance of this research is that the root of numerous firms' inefficiency after privatization lies in the privatization process. The goals of privatizing firms are to improve the efficiency of privatized firms, maintain employment levels, and finally raise funds from privatizing public firms. It could be some conflicts between these goals. On the other hand, managers of public firms will resist privatizing these firms, because they will see their job situation and future in danger. Also, the privatization organization is one of the economic ministry’s subsets which has not enough power and... 

Peer to peer networks and especially peer to peer live video streaming systems are becoming more and more popular these days. To disseminate the video chunks in a live P2P video streaming system all users should contribute in uploading the video chunks; however there are some selfish peers who tend to download video chunks from the network while they do not upload any data to the network; these peers are called free-riders. With incorporating the incentive mechanisms in peer to peer live video streaming systems the chance of free-riders to get the full video or the video with the intended quality will be very low. In this research we propose a push-pull live video streaming system with a... 

Electricity distribution systems are dynamically expanded in anticipation of new demands. Cost and reliability are the most important factors in finding the optimal plans for network expansion. Recently, implementation of incentive reliability regulations has accentuated the role of reliability considerations in distribution systems studies. This is because such incentive schemes create a direct link between distribution companies' revenues and their service reliability. Thus, these schemes have changed the role of reliability from a technical constraint to an economic factor. In this occasion, distribution companies require new techniques to incorporate the effects of incentive reliability... 

This thesis aims to create an electronic health system for transferring, verifying, and monitoring patient data. Blockchain technology is used in this system. In this system, the patient can communicate with the relevant hospital via an authentication protocol and transmit his data to the hospital. The hospital levels the patient's data creates the patient's treatment prescription and shares it with the pharmacy and insurance company to facilitate the patient's effective treatment. Blockchain technology has been used in a variety of electronic health systems. There are several problems with these systems, including the incorrect use of blockchain, a lack of comprehensiveness, a lack of...