Constellation Shared Multiple Access - A Noma Scheme for Increased User Capacity in 5G MMTC

Constellation Shared Multiple Access - A Noma Scheme for Increased User Capacity in 5G MMTC

Authors

Kiran V. Shanbhag1 and Savitha H. M.2, 1Anjuman Institute of Technology and Management, India, 2St Joseph Engineering College, India

Abstract

While the legacy cyclic prefix orthogonal frequency division multiple access is retained as the preferred multiple access scheme for 5G enhanced mobile broadband the research is now focussed on the multiple access schemes for massive machine type communication (mMTC) and ultra-reliable low latency communication .Though orthogonal multiple access schemes provide simple reception, they limit number of simultaneous user equipment as against the primary requirement of mMTC. On the other hand, the various non-orthogonal multiple access schemes which have been proposed so far as the likely solution, need complex successive interference cancellation receivers. So a simplified scheme named constellation shared multiple access is proposed here which substantially increases the number of simultaneous users to be served within a single resource block (RB) in LTE or 5G New Radio, thus aiding the massive connectivity requirement of mMTC. This is achieved by differentiating among the users in constellation domain. Moreover, the simple architecture compatible with 5G eMBB makes it a strong contender multiple access contender for 5G mMTC.

Keywords

Non orthogonal multiple access, Quality of service, Massive connectivity, 5G, Successive interference cancellation receiver, mMTC.

https://aircconline.com/ijcnc/V14N3/14322cnc05.pdf

#MQTT #network #DoSAttack #iot

Performance Evaluation of Different Raspberry Pi Models as MQTT Servers and Clients

Authors

Trent N. Ford, Eric Gamess and Christopher Ogden, Jacksonville State University, USA

Abstract

Performance analysis for devices in Internet of Things (IoT) environments is an important consideration, especially with their increasing integration in technological solutions, worldwide. The Single Board Computers (SBCs) of the Raspberry Pi Foundation have been widely accepted by the community, and hence, they have been incorporated in numerous IoT projects. To ease their integration, it is essential to assess their network performance. In this paper, we made an empirical performance evaluation of one of the most popular network protocols for IoT environments, named the Message Queuing Telemetry Transport (MQTT) protocol, on Raspberry Pi. To do so, we set up two different testbeds scenarios and assessed the performance with benchmarks. At the software level, we focused on Mosquitto, a popular open-source MQTT broker implementation and client library. Our principal metric is the transmission time, but we also investigated the throughput. In our experiments, we varied several parameters, such as the size of the payload of the published messages, the WiFi bandwidth, the QoS level, the security level (MQTT vs. MQTT with TLS), and the hardware for the clients and broker. We focus mainly on packet sizes ranging from 100 to 25,000 bytes. We also investigate how these low-cost devices handle a TCP SYN flood attack. In the research work presented within this paper, we aim to guide developers, researchers, network administrators, and hobbyists who plan to use these low-cost devices in an MQTT or IoT network by showing the performance that they should expect according to different Raspberry Pi options.

Keywords

MQTT, Mosquitto, Benchmark, Performance Evaluation, Raspberry Pi, DoS Attack.

https://www.youtube.com/watch?v=LGEy6ePOSkE&list=PLpTbECDq5OWA7YEHmDZxLz6DDrmjDc7r3