Low Power Wide Area Networks (lpwan): Technology Review And Experimental Study on Mobility Effect

LORA ALLIANCE

The LoRa Alliance [28] is a group of companies, developers and manufacturers all over the world that come together to develop a standard for low power, low cost, secure and long-range solution of ever increase domain of internet of things. The LoRa Alliance has been in existence since March 2015. Figure 8 shows the current sponsored members of
Lora Alliance.

Figure 8: LoRa sponsor members [28].
Along with being a Sponsored member, the group also offers other levels of membership like Contributor, Institutions, Adopter and Public. Each of these members have different levels of rights and privileges in the group.
The goal of this non-profit organization is to create common standard that can be used to deploy LPWAN all over the world by standardizing knowledge and interoperability between operators all over the world in a single global standard.

3. LORAWAN

The LoRaWAN is a communication protocol based on the LoRa modulation technique. LoRa modulation technique was first invented by a French start up Cycleo and then later in 2012 it was acquired by Semtech [31]. LoRaWAN communication protocol belongs to the second layer of OSI model which is the MAC layer (Media Access Control Layer). LoRaWAN as a protocol has various benefits over other wireless communication protocols. Some of the advantages are:

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  Bi-directional communication
  
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  End to end security using AES encryption
  
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  Over the air registration of end nodes
  
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  Low power
  
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  Adaptive data rate
  
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  Long range
  
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  Low cost
  

LoRaWAN networks are implemented as a star topology which are composed of end devices, gateways, network servers and application server. Along with being simple as compared to a mesh network, one of the advantages of implementing star network topology is that it helps with the power consumption of end devices. In a mesh topology, all the devices in network communicate with every other device in the network. Although this helps to increase the range of communication, it does drain the power from end devices since they are in constant state of communication. This problem is solved in case of LoRaWAN by implementing an overlapping star network where the end device communicates with the best gateway thus decreasing the number of devices it needs to communicate and in turn reducing the power consumption. LoRaWAN also provides the end to end network security for data transmitted from end devices till it reaches the server.

Adaptive Data Rate (ADR) is one of the very important characteristics of

LoRaWAN network which helps save power consumption for end devices. This is done by regulating both the data rate and the radio frequency output of the end nodes. This scheme allows the gateways to receive a number of packets at the same time from multiple end nodes [68].

4.