High/ultra-high speed data connections are currently being developed, and by the year 2020, it is expected that the 5th generation networking (5GN) should be much smarter. It would provide great quality of service (QoS) due to low latency, less implementation cost and high efficiency in data processing. These networks could be either a point-to-point (P2P) communication link or a point-to-multipoint (P2M) communication link, which, P2M is also known as multi-casting that addresses multiple subscribers. The P2M systems usually have diverse nodes (also called as `Things') according to services and levels of security required. These nodes need an uninterrupted network inter-connectivity as well as a cloud platform to manage data sharing and storage. However, the Internet of Things (IoT), with real-time applications like in smart cities, wearable gadgets, medical, military, connected driver-less cars, etc., includes massive data processing and transmission. Nevertheless, integrated circuits (ICs) deployed in IoT based infrastructures have strong constraints in terms of size, cost, power consumption and security. Concerning the last aspect, the main challenges identified so far are resilience of the deployed infrastructure, confidentiality, integrity of exchanged data, user privacy and authenticity. Therefore, well secured and effective cryptographic algorithms are needed that cause small hardware footprints, i.e. Lightweight Cryptography (LWC), also with the provision of robustness, long range transfer of encrypted data and acceptable level of security.In this paper, the implementation, challenges and futuristic applications of LWC algorithms for smart IoT devices have been discussed, especially the performance of Long-Range Wide Area Network (LoRaWAN) which is an open standard that defines the communication protocol for Low-Power Wide Area Network (LPWAN) technology.