**Part 4**

**Real World Applications** 

20 Will-be-set-by-IN-TECH

210 Real-Time Systems, Architecture, Scheduling, and Application

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53(6):744–759.

**10** 

*Iran* 

**Linearly Time Efficiency in Unattended** 

In the past decades, wireless Sensor Networks (WSNs) attracted many researchers. A lot of them considered important issues such as: routing, security, power awareness and data abstraction, But security is prior common assumption in the most of works. On the other hand, WSNs should collect small size and especially secure data in real-time manner. This problem is considered because sensor nodes are small, low power with low storage. Therefore, classical algorithms maybe inapplicable, i.e. considering constrained sensor, these algorithms cannot guarantee the security of data. The aforementioned problem is very critical in the new generation of WSNs referred to as Unattended or disconnected wireless

The disconnected networks are established in critical or military environments. Hence, sink or collector is unable to gather data in real-time manner. Moreover, the network will be leaved unattended and will be periodically visited. This property provides some threats such as discovering and compromising sensor nodes by adversary without detection. Moreover, adversary invisibly performs to be intractable and unpredictable. Also, some adversary is curious and aims just to disclose data, while some aims search data to replace them with forged. The third kind of network adversary whiles to inject invalid data to corrupt network called DoS attack or mislead sink. In such setting, the main challenge is

In this research, we propose scheme that firstly shares generated data and encodes them to provide confidentiality and integrity. Moreover, utilizing efficient mathematical solution, every sensor with unique identification encodes shares, in which encoding process is oneway with initial boundary conditions. Then a linear signing algorithm applies to provide authentication and prevent DoS attack. In addition, in order to defend curious adversary, the signed generated data will be broadcasted to the neighbour sensors. Every neighbour uses network-encoding for received shares and homomorphic signs to remove previous signature and generate unique signature. This process decrease size of total received shares. *Organization:* Section 2 reviews the related work of UWSNs. Section 3 sketches our proposed algorithm including applied network coding, homomorphic and mathematical solution. In section 4 we have demonstrated our scheme efficiency implemented by Maple. We have

**1. Introduction** 

sensor networks.

assurance about data survival for long time.

ended this chapter with conclusion section.

Faezeh Sadat Babamir and Fattaneh Bayat Babolghani

**Wireless Sensor Networks** 

*Shahid Beheshti University of Tehran* 
