In 1969, US government introduced a technology for transmitting the information from one place to another. It can send data or the information widely. It was known as DARPANET (Defence Advance Research Project Agency Network).
Image credit : ARPANET
It was mainly designed for the military purpose, for secret information transfer. It was spread in wide area which was beneficial war time. This network came to be known as the Wide Area Network (WAN). Later in 1972, the DARPANET was renamed as ARPANET (Advance Research Project Agency Network) which was used locally thereafter.
Gradually, the technology developed and the Internet of Things (IoT) was introduced. IoT is the technology which uses wireless and sensor based technology. Wide area network has been around from decades. But the increasing technology & demands for low cost connectivity for the IoT and improvement in power consumption and cost is driving more interest.
Image credit: Link-Labs
Further working on the demands Low Power Wide Area Network (LPWAN) was introduced. Earlier in 80’s & 90’s similar topologies & network architecture like Alarm Net, ARDIS Network in 1999-2000, GPRS 2G/3G in 2000, then came the ONRAMP, SIGFOX, CYCLEO in 2010 & then the LoRa, 3GPP, Link Labs in 2014-2016 etc. were used but were not called as LPWAN. LPWAN technology is mainly designed for M2M networking environment with decreased power requirements, longer range & low cost than a mobile network i.e. to allow long range communication at a low bit rate among things, such as sensors operated on battery.
Image credit: iotNet
Improvements in Silicon technology have lowered power consumption to where it has become viable for battery-powered wireless sensor nodes. This technology is cost optimised & can also be operated in remote areas & the areas where it is hard to reach. It is easy to implement & deploy & serve a large no. of vertical markets such as manufacturing wearables, utilities or transport. Various anticipate reaching up to 5 billion LPWAN connections in 2020 & generating about US $1 billion in 2018.
The LPWAN technology enables connectivity for network of devices that require less bandwidth than what our home equipment provides. Bluetooth, ZigBee & Wi-Fi are adequate for consumer-level IoT implementations or these implementations can be known as short range technologies.
Image credit: Ensembletech
The need for LPWAN technology is much greater in Industrial IoT, Civic & Commercial applications. The term LPWA covers standardized cellular as well as proprietary wireless technologies such as LoRa, SIGFOX. LPWAN will support devices requiring lower mobility, low power consumption, long range & cost & security. There are different options for developers of IoT network such as LoRa from Semtech, can be used to roll out a dedicated private LPWAN network for a group of wireless nodes or a public LPWAN network such as SIGFOX can be used to avoid the need to install, connect & manage the base stations. Nowadays other LPWAN’s are also being developed with new protocols such as Weightless.
Video credit: LoRa Alliance
LoRa is a patented technology developed by CYCLEO (Grenoble, France) & acquired by Semtech in 2012. It uses license-free sub GHz radio frequency bands like 169 MHz, 433 MHz, 915 MHz, etc. It is proprietary, Chip Spread Spectrum (CSS) radio modulation technology for LPWAN used by LoRaWAN, Haystack Technologies & Symphony Link. LoRaWAN typically uses a star-of-stars topology in which gateways are a transparent bridge relaying messages between devices & a central network server in the backend. LoRaWAN is a LPWAN specification intended for wireless battery operated things in regional, national or a global network. LoRaWAN targets key requirements of IoT such as secure bi-directional communication, mobility & localization services. Gateways are connected to the network server via standard IP connections while end devices use single-hop window communication with different data rates do not interfere with each other and create a set of “virtual” channels increasing the capacity of gateway. LoRaWAN data range is from 0.3kbps to 50kbps.
Image credit : Simtech
LoRaWAN maximizes the battery life of end-devices and overall network capacity by Adaptive Data Rate (ADR) scheme. LoRaWAN is an open LPWAN data link standard maintained by LoRa Alliance. In OSI model, LoRaWAN would correspond to the Data Link Layer (L2) & then its sub-layer MAC Layer. On 16th June 2015 version 1.0 of LoRaWAN specification was released.
Another LPWAN technology for IoT network is SIGFOX. SIGFOX is French Company founded in 2009, which builds a wireless network to connect low-energy objects such as electricity meters, smartwatches & washing machines which need to be continuously on & emit small amount of data. SIGFOX employs a proprietary technology that enables communication using the Industrial, Scientific & Medical ISM radio band which uses 868 MHz in Europe & 902 MHz in US. It utilizes wide-reaching signal that passes freely through solid objects which is known as “Ultra Narrowband” & uses low energy so it is termed as Low Power Wide Area Network (LPWAN). This network is based on One-Hop Star Topology & requires a mobile operator to carry generated traffic & the signal can also be used to reach underground objects.
Video credit: Sigfox
The existing standards of SIGFOX communication supports up to 140 uplink messages a day which carry a payload of 12 bytes & up to 4 downlink messages per day which can carry a payload of 8 bytes. It has wireless throughput up to 100bits/sec. The density of cells in SIGFOX network is based on an average range of 30-50km in rural areas & in urban areas due to more obstruction and noise the range may be reduced to 3-10km. SIGFOX state lines of sight messages could travel over 1000km. SIGFOX may be used in home & consumer goods, energy communications, healthcare, transportation, remote monitoring & control, security etc.
“LPWAN : Changing The World “
References : LoRa Alliance