# FuGeF: A Resource Bound Secure Forwarding Protocol for Wireless Sensor Networks
## 1 Introduction  
Routing and security are two of the most prominent research challenges in WSN that have gained much ground, due to the emergence of Cyber-Physical Systems (CPS) and Internet of Things (IoT) that employ sensor devices for communication. Although the sensor has resource constraints in computation, memory, bandwidth and energy, a routing protocol is required to provide a safe and reliable path to ensure an end to end communication in a network [1]. This path is built by selecting appropriate nodes that are traversed from one end of the network to another. However, several security approaches used by routing protocols are inefficient in mitigating spatio-temporal attacks. This is because of the high resource consumption of the pertinent mechanisms employed for the security solutions on the sensor node. Therefore, resource bound security solutions are highly needed to provide minimal active security protection.  
Resource bound security solution is the process of using improved protocol's operation semantics to provide adequate security. It can be kept active or activated when needed to optimize protocolperformance while minimizing security threats using minimal resource consumption [2]. This solution was proven successful in [2] and has been applied to various routing protocols in [2; 3; 4] to mitigate spatio-temporal attacks. Spatio-temporal attacks are attacks plotted in a network after extensive correlation analysis of an existing communication pattern in the network. In other words, attackers are able to determine temporally the presence of data in nodes and importantly, to predict the position (spatially) of the next forwarding node [5]. Attackers successful in such siege can further decide to drop all (blackhole), partially drop (grayhole), or Insert data into the packet. Any of the attacks can drastically degrade the performance of a network to an undesirable level.  
In [3], a DWSIGF protocol was proposed to mitigate the black hole attack. It introduced a dynamic collection window period to create a possible time shift in the protocol's semantics. The protocol improved performance in protection against security attacks. However, the utilization of a distance based parameter (only) for forwarding node selection in the network has simplified spatio-temporal predictions, causing strategic placement of malicious nodes to succeed in enabling substantial packet losses in the network. Furthermore, it achieved a poor trade-off between its security performance and base performance, such that either inefficient utilization of the constrained resources is made to achieve the minimal security or the base performance is maintained by efficiently utilizing the resources at the expense of security.  
In this paper, we propose a Fuzzy-based Geographic Forwarding protocol (FuGeF) to improve node selection. The protocol first utilizes three parameters: remaining energy, connectivity cost, and progressive distance for node selection, then, employs a Fuzzy Logic System (FLS) for decision-making. The goal of FuGeF is to identify appropriate forwarding nodes that would mitigate packet loss as well as provide a better trade-off between security and base performance. Extensive simulation experiments have been conducted to evaluate the performance of the proposed FuGeF with the DWSIGF protocol. The results obtained show that the FuGeF achieves a higher performance in terms of packet delivery ratio and minimizes the possibility of choosing an attacker as compared to DWSIGF protocol.  
The rest of the paper is organized as follows: Section 2 briefly discusses some related works. Section 3 describes the base protocol, while Section 4 describes our proposed protocol. Performance evaluations of the base and proposed protocol were discussed in Sections 5 and 6 presents the conclusion and future works.