Formal Specification and Validation of a Localized Algorithm for Segregation of Critical/Noncritical Nodes in MAHSNs

Abstract

Timely segregation of critical/noncritical nodes is extremely crucial in mobile ad hoc and sensor networks. Most of the existing segregation schemes are centralized and require maintaining network wide information, which may not be feasible in large-scale dynamic networks. Moreover, these schemes lack rigorous validation and entirely rely on simulations. We present a localized algorithm for segregation of critical/noncritical nodes (LASCNN) to the network connectivity. LASCNN establishes and maintains a k-hop connection list and marks a node as critical if its k-hop neighbours become disconnected without the node and noncritical otherwise. A noncritical node with more than one connection is marked as intermediate and leaf noncritical otherwise. We use both formal and nonformal techniques for verification and validation of functional and nonfunctional properties. First, we model MAHSN as a dynamic graph and transform LASCNN to equivalent formal specification using Z notation. After analysing and validating the specification through Z eves tool, we simulate LASCNN specification to quantitatively demonstrate its efficiency. Simulation experiments demonstrate that the performance of LASCNN is scalable and is quite competitive compared to centralized scheme with global information. The accuracy of LASCNN in determining critical nodes is 87% (1-hop) and 93% (2-hop) and of noncritical nodes the accuracy is 91% (1-hop) and 93% (2-hop).

Hybrid subnet-based node failure recovery formal procedure in wireless sensor and actor networks

“…In most of the relevant work PADRA 16 and restoring actor connected coverage (RACE), 41 it is focused on failure recovery of critical actors, while our proposed algorithm is for failure recovery of critical sensor, actor, and gateway nodes. Unlike proactive approach PADRA which uses depth-first search (DFS) for identification of critical nodes, we have proposed a localized cut-vertex detection procedure for identification of critical nodes performed at subnet level reducing time complexity.…”

“…In this way, the recovery process is completed by cascading, that is, backup B of A is moved to position of A and newly backup of B is moved to position of B (lines [34][35][36][37][38][39]. If backup node B is critical and its backup is other than its primary, then it notifies to its backup and moves to position of its primary by cascading (lines [40][41][42][43] [34][35][36][37][38][39]. If the backup is critical and its backup is other than its primary, then the recovery procedure takes time NK (lines [40][41][42][43].…”

“…If backup node B is critical and its backup is other than its primary, then it notifies to its backup and moves to position of its primary by cascading (lines [40][41][42][43] [34][35][36][37][38][39]. If the backup is critical and its backup is other than its primary, then the recovery procedure takes time NK (lines [40][41][42][43]. In this way, the maximum time complexity of the algorithm in terms of Big O is N K .…”

Formal analysis of subnet-based failure recovery algorithm in wireless sensor and actor and network

“…Z-notation and X-machine are used for the formal specification of multi-agent systems with a dynamic behaviour and structures (Ali et al 2012). VDM-SL and Z based formal models are developed for WSANs for safety critical systems Alnuem et al 2014;Riaz et al 2015).…”

Formal verification and validation of a movement control actor relocation algorithm for safety–critical applications

“…Unlike these approaches, our work is based on complementary verification and validation techniques that allow systematic and comprehensive investigation of the model properties and correctness of the proposed algorithm. Moreover, we used [24] to analyze the impact of repulsion on topology resilience.…”