A Sparse Merkle tree is based on the idea of a complete Merkle tree of an intractable size. The assumption here is that as the size of the tree is intractable, there would only be a few leaf nodes with valid data blocks relative to the tree size, rendering the tree as sparse. We present a novel approach called Minimum distance path algorithm to simulate this Merkle tree of intractable size which gives us efficient space-time trade-offs. We provide the algorithms for insertion, deletion and (non -) membership proof for a leaf in this Compact Sparse Merkle tree.

Parikshit is Manipal University's first 2U class Nano satellite mission. The command and data-handling department is developing the computer architecture for the satellite missions that have multifaceted requirements. The satellite is carrying a thermal camera as the payload for obtaining thermal images of the Indian subcontinent. With the space being a dynamic environment, it is required from an autonomous system to be robust and redundant. The system is expected to perform activities in real time, and with utmost precision given to computations and ability to recover from failures. In such systems, data handling and power management is a vital aspect to mission life. The computer acts as the brain of a satellite, which is expected to operate at constrained resource environments. A real time operating system is used in such cases where deterministic execution is of prime importance. This paper describes how the real time operating system is ported to an STM32F207 to control the satellite's mission life. A comparative study of how this RTOS is best suited for our mission is also presented. The RTOS is specifically designed to effectively manage power in this dual controller system. Results of 14 orbit simulation for control and attitude determination algorithms are also shown. The software design here is expected to monitor and control the execution of both the on-board controllers. The design of the software will be compatible with other university missions as well because most of them base their design on similar hardware bus. An analysis of the software execution on the Parikshit mission is described and results show how the chosen R TOS performs on a dual controller based system.

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The nexus between climate change and military security is essentially non-existent in Pakistan’s security discourse. The paper argues for the connection between these two sectors - from the Copenhagen School framework of security - and presents how threats from climate change threaten Pakistan’s military security. Most notable threats, in severity and frequency, are sea level rise, cyclone risks, drastic floods, warming patterns, and glacial melting. Sea level rise and cyclone risks impact naval assets and infrastructure while warming patterns and glacial melting affect troop movement, deployments, and logistics. Resultantly, military training, force capacity, and operational readiness is affected. Threats are more potent in strategically significant locations (Siachen, Sindh, and Punjab) which house important forward military bases. The paper provides actionable recommendations that create foundations for future steps as well.

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