Nowadays, demand for low power, compact, mobile and flexible computing machines that interconnects is growing rapidly.
6LoWPAN, therefore, allows for the smallest devices with limited processing ability to transmit information wirelessly using an internet protocol IPV6.
The concept was created because engineers felt the need of the smallest devices which were unable to participate in the Internet of Things and were left out.
6LoWPAN is an acronym that combines of IPV6 over Low-power Wireless Personal Area Networks (LoWPAN).
It’s a low power wireless mesh network where every device has their own address that allows the device to connect with the internet using open standards. The targetted applications are those where there is need of wireless internet connectivity at lower data rates for devices with very limited form factor.
6LoWPAN is low cost, short range, low memory usage, low bit rate and comprises of edge router and sensor nodes . Edge router is the core of 6LoWPAN network that link 6LoWPAN network to the other IP internet. It is responsible for routing 6LoWPAN packet to the IPv6 packet, and assigning IPv6 prefixes in the 6LoWPAN network.
The routing mechanism for 6LoWPAN network are: mesh-under and route over.
The mesh-under router mechanism permits layer 2 routing, whereas route-over mechanism routing with the aids of network layer .
The maximum transmission packet size in a standard IPv6 is 1024 bytes whereas it is reduced to 127 bytes in 6LoWPAN.
In IPv6 network, 40 bytes is reserved for IPv6 header, 25 bytes for MAC header, additional 8 bytes may also be used for UDP headers. This will make left-over payload to be about 54 bytes in 6LoWPAN. To offset for small available frame size of a payload, adaptation layer has been established by IETF to reduce IPv6 overhead header.
High IPv6 header compression, Bootstrap, multihoming and flexibility are some of the important features. since it is IP-based, all these devices can talk to each other with no interference issues.
6LoWPAN can communicate with 802.15.4 devices as well as other types of devices on an IP network link like WiFi .The ZigBee IP is also built on the IEEE 802.15.4 standard, but unlike 6LoWPAN, it cannot easily communicate with other protocols.
6LoWPAN uses AES-128 link layer security which is defined in IEEE 802.15.4 and this provides link authentication and encryption.
Further security is provided by the transport layer security mechanisms. This is defined in RFC 5246 and runs over TCP/IP protocol .
A little about about IPv6 :
IPv6 is the latest version of internet protocol and provides an unique identification and location system for computers on networks across the internet.
IPv6 utilizes 128-bit Internet alphanumeric addresses. Therefore, it can support 2^128 Internet addresses (More than three hundred forty undecillion !! ).
IPSEC being an inbuilt feature in IPv6 it adds onto its security. It also supports for quality of service (QoS). It allows direct addressing instead of NAT(Used in IPv4) due to vast address space.
Basic requirements for 6LoWPAN :
- The device must have sleep mode in order to support battery saving
- Minimal memory requirements.
- Routing overhead should be lower.
Advantages of 6LoWPAN :
- Support robust , self healing and scalable mesh networking.
- Works efficiently with open IP standardized including UDP , TCP , COAP , HTTP , MQTT and web sockets.
- In this network leaf nodes can be in sleep mode for a long duration of time.
- It also offers one to many and many to one routing.
- It offers end to end IP addressable devices which don’t require any gateway , only a router which can connect this network to IP.
- It is a standard: RFC6282.
One clear advantage with 6LoWPAN is the low power consumption and the meshing capability, enabling the wide dispersion of battery or battery-less sensor nodes into the field. In addition, as the technology evolves, so does the 6LoWPAN system along with it.
While selecting a wireless technology factors that must be considered such as, power consumption, data rate, range and signal propagation (sub-GHz vs 2.4 GHz), and complying with any FCC or regional air time constraints that may be critical to the application. As a whole, these considerations will ultimately favor one technology or the other.
According to a recent survey the number of IP enabled embedded devices are growing at a very rapid rate and the progress made in field of low-power radio, microcontroller and microelectronic technology over the past decade, caused a drift in the industry for smart embedded devices called smart objects to turn out to be IP-enabled,making 6LoWPAN a future-proof solution in the IoT industry .
A brief about what we do at PsiBorg Technologies:
We are specialized in hardware development , wired and wireless connectivity protocols, security, device management,optimized computing at the edge, and complete software for IoT end points and gateways.
We are focused on designing and developing a range of smart products and industry solutions with deep customer insights and end user inputs.