Sharif Digital Repository

Smartphones can be viewed as resource pools capable of communicating with their outside world. Such communication capabilities provide unique opportunity for sharing resources, which would result in new possibilities for end users. In this paper, we present a new framework designed for managing mobile local networks, also referred to as Mobile Clouds. In this framework, mobility of nodes is managed by selecting one leader for each cloud, which is responsible for all cloud-level decisions, as well as processing all incoming data from other users. We also evaluate and discuss our proposed framework under different scenarios  

Smartphones can be regarded as resource pools which are capable of communicating with their outside world using both short-range and long-range links. Such communication capabilities provide a unique opportunity for sharing resources, resulting in new possibilities for end users. In this paper, we present a new data update and processing scheme, designed for local networks of mobile devices which are formed with resource sharing in mind  

In this paper, we propose a new packet prioritization scheme in order to exploit the full-duplex (FD) capability of the access point (AP) more efficiently, in an asymmetric IEEE 802.11-based WLAN, i.e., only the AP has the in-band FD communications capability. In this respect, we consider a modified version of IEEE 802.11 MAC protocol such that at any transmission opportunity in which AP has the role of the transmitter or the receiver, it does the best to select a partner packet to be simultaneously received or transmitted, respectively. The key feature of our proposed partner packet selection scheme is to reduce the idle time intervals that in an FD transmission opportunity, due to... 

The application of digital technologies in power systems has resulted in an evolutionary replacement of electromechanical devices with numerical ones featuring internal digital processors with communication capabilities. A substation automation system (SAS) deploys substation operation functions, including control, protection, monitoring, and measuring. Ethernet technology and local area networks (LANs) make it possible to design substation communication architectures with greater reliability, availability, speed, and cost savings than conventional hard-wired systems. This paper proposes a new method to describe topologies of the SAS as an interconnected network. The concept of data... 

A Wireless sensor network (WSN) is composed of numerous sensor nodes with both insecurely limited hardware and restricted communication capabilities. Thus WSNs suffer from some inherent weaknesses. Key management is an interesting subject in WSNs because it is the fundamental element for all security operations. A few key management models for heterogeneous sensor networks have been proposed in recent years. In this paper, we propose a new key management scheme based on elliptic curve cryptography and signcryption method for hierarchical heterogeneous WSNs. Our scheme as a secure infrastructure has superior sensor node mobility and network scalability. Furthermore, we propose both a periodic...