A Novel Emergency Light Based Smart Building Solution: Design, Implementation and Use Cases
Weitao Xu, Jin Zhang, Jun Young Kim, Walter Huang, Salil S. Kanhere, Sanjay K. Jha, Wen Hu, Prasant Misra
11 A Novel Emergency Light Based Smart BuildingSolution: Design, Implementation and Use Cases
Weitao Xu, Jin Zhang, Jun Young Kim,
Member, IEEE , Walter Huang, Salil S. Kanhere, Sanjay K. Jha, Wen Hu,Prasant Misra,
Senior Member, IEEE
Abstract —Deployment of Internet of Things (IoT) in smartbuildings has received considerable interest from both theacademic community and commercial sectors. Unfortunately,widespread adoption of current smart building solutions isinhibited by the high costs associated with installation andmaintenance. Moreover, different types of IoT devices fromdifferent manufacturers typically form distinct networks anddata silos. There is a need to use a common backbone networkthat facilitates interoperability and seamless data exchange in auniform way. In this paper, we present EMIoT, a novel solutionfor smart buildings that breaks these barriers by leveragingexisting emergency lighting systems. In EMIoT, we embed awireless LoRa module in each emergency light to turn theminto wireless routers. EMIoT has been deployed in more than50 buildings of different types in Sydney Australia and hasbeen successfully running over two years. We present the designand implementation of EMIoT in this paper. Moreover, we usethe deployment in a residential building as a use case to showthe performance of EMIoT in real-world environments andshare lessons learned. Finally, we discuss the advantages anddisadvantages of EMIoT. This paper provides practical insightsfor IoT deployment in smart buildings for practitioners andsolution providers.
Index Terms —IoT, Smart Building, LoRa, Emergency Light
I. I
NTRODUCTION
Buildings play a significant role in our modern society asthey consume about of global energy and we spend80–90% of our lives in buildings (e.g., homes, offices) [1].With the advent of Internet of Things (IoT), the conceptof building IoT (BIoT) is becoming increasingly popularnowadays. BIoT takes the idea of the IoT and applies itto commercial buildings. A BIoT system can connect allthe smart devices (commonly known as things/objects) thatare distributed across the building in an efficient and cost-effective manner. Furthermore, with big data and artificialintelligence (AI) technology a BIoT system can obtain valu-able information from these data and immediately optimiseand fully automate the buildings performance. BIoT systemscan improve utility of such buildings immensely such asreducing energy usage, facilitating rapid and efficient repairand maintenance. For example, the smart building deployedby Intel at Bangalore India leads to 20–30% improvement in
Weitao Xu is with Department of Computer Science, CityUniversity of Hong Kong. Email: [email protected]. Salil S.Kanhere, Sanjay Jha and Wen Hu are with School of ComputerScience and Engineering, University of New South Wales, Australia.Email: { salil.kanhere,sanjay.jha,wen.hu } @unsw.edu.au Jin Zhang, JunYoung Kim and Walter Huang are with WBS Technology, Australia.Email: { jin.zhang,jun.kim,walter } @wbstech.com.au Prasant Misra is withTATA Consultancy Services Ltd., Email:[email protected] Fig. 1: An overview of EMIoT.space utilisation and 10% reduction in energy consumptionevery year [2].While a significant number of infrastructures, technologies,and applications of BIoT have been developed, several barriershave prevented their widespread adoption such as hetero-geneity of data, lack of ubiquitous connectivity and security.Among these challenges, the lack of low-cost backbone net-work that can achieve ubiquitous connectivity is the primaryobstacle. Existing communication technologies have been suc-cessful in achieving ubiquitous connectivity but the solutionsare expensive, lack flexibility and robustness. Traditionally,large BIoT networks have been a complex, fragmented systemof different standards, devices, and services, making them ex-traordinarily hard to manage. Smart services and applicationsare delivered through a number of protocols, including Wi-Fi, Bluetooth Low Energy (BLE) and Zigbee, which presentsa major challenge to different manufacturers and vendors.For example, a smart building may have a BLE network tosupport one or multiple BLE IoT apps and another Zigbeenetwork to support one or more Zigbee IoT apps. To connectWi-Fi enabled smart devices, we need to add another Wi-Finetwork. The consequence is that we will have a complex setof networks that is challenging and costly to maintain andsupport. Unfortunately, most existing solutions are based onthis strategy such as [3], [4]. How to consolidate multipleheterogeneous networks into a single converged network ina low-cost way to simplify IoT endpoint onboarding andmanagement remains an open problem.This article aims to address this challenge by proposinga BIoT solution wherein, a common backbone network fa-cilitates interconnectivity and seamless data exchange be-tween different IoT devices and networks deployed within a r X i v : . [ c s . N I] J u l Fig. 2: A conceptual BIoT framework .the building. Specifically, we present an emergency lightingIoT system for smart buildings—EMIoT (A demo of EMIoTcan be found in [5]). The key feature of EMIoT is that itrequires low CAPEX (capital expenditure) and is easy todeploy because it is built on top of a common facility inevery buildings—emergency lights. In EMIoT, the ubiquitousemergency lighting system forms an interconnected backbonenetwork with the help of LoRa communication technology.LoRa communication technology is one of the standards inLow-power Wide-area Network (LPWAN). Compared to otherIoT communication technologies such as Wi-Fi and ZigBee,LPWAN features low-cost, low-power and wide coveragewhich make it highly suitable for BIoT smart objects whoserequirements are low data rate, low energy consumption,and cost effectiveness. Built on the strength of LoRa andubiquitous emergency lights, EMIoT presents a low cost andeasy to deploy smart building solution that can provide a singleconverged network to connect any objects in a building. Fig. 1provides a brief overview of EMIoT.We make two contributions in this article. First, we presenta novel emergency light based smart building solution EMIoT.To the best of our knowledge, this is the first smart buildingsolution that is built on top of emergency lights. Compared tocurrent BIoT architectures, EMIoT presents several advantagesas will be discussed later in this article. Second, EMIoT hasbeen deployed in more than 50 buildings of different typessuch as residential building, office, and shopping centres inSydney Australia and successfully running over two years. Weshare experience and lessons learned during deployment toprovide practical insights for smart building solution providers.The rest of the paper is organised as follows. Section IIpresents a conceptual BIoT framework that can be used byresearchers and engineers as a reference to design their ownBIoT solutions. Section III discusses the current challengesin BIoT. Then, we present the design details of EMIoT inSection IV. Next, we share our experience and lessons learnt in Section V. Section VI discusses advantages and disadvantagesof EMIoT and finally Section VII concludes the paper.II. C
ONCEPTUAL BI O T F
RAMEWORK
Although the concept of BIoT has been around for decades,a uniform and agreed BIoT reference framework and standardis lacking. In this paper, we present a conceptual BIoTframework that can be used as guide to design smart buildingsystems (see Fig. 2).
Layer 5: Users.
It is possible that a BIoT system hasdifferent types of users such as administrator, customer andsystem support. So this layer identifies the types of users whointeract, either directly or indirectly, with the BIoT solution.This layer is used to assist service/solution vendors to definewho their final clients are. Understanding all the users alsoenables an organisation to identify how their solution can meetdifferent user requirements.
Layer 4: Data Management.
One of the most vital func-tions of a BIoT solution is the capability for an organisationto ‘manage’ their devices and data through a diverse rangeof activities including: device connection management, datacollection and processing, event tracking and handling, an-alytics, and interfaces to external systems. A BIoT systemcan generate a large volume of data such as temperature,energy usage and people’s location. Traditional data storage isimportant but far from enough. A smart BIoT system shouldbe able to turn large amounts of data into useful, actionableinformation that can make the solution a truly smart system.The BIoT system can adopt some emerging technologies suchas Artificial Intelligence (AI) and Blockchain to enhance thecapability of the system.
Layer 3: Connectivity.
Connectivity is an indispensablepart of any BIoT solution. Devices can be connected viaeither wired communication or wireless communication tech-nologies. A number of connectivity technologies have beeninvented to meet the diversified requirement of IoT, including: wired connectivity, Wireless Local Area Network (WLAN)such as Wi-Fi, Low Power Wide Area Network (LPWAN)such as LoRa, and Wireless Wide Area Networks (WWAN)such as 4G and 5G. Due to the heterogeneity nature of BIoT,there may exist several communication technologies in a singleBIoT system. For example, BLE and Wi-Fi are often used toexchange data between personal devices such as smartphoneand laptop. LPWAN is used in smart meters which do notrequire frequent communication. In some BIoT systems, 4Gor 5G is used to connect a gateway to a remote server.Therefore, there is no clear difference between IoT and BIoTin terms of connectivity. This layer implements functionalityfor managing connected devices in a scalable and securemanner. Practitioners need to select proper communicationprotocols from different aspects such as power consumption,communication distance, bandwidth, and capacity.
Layer 2: Gateway.
A gateway is a bridge between enddevices and users. It uploads data from an end device to aremote server for the user to monitor and access them. Mean-while, the commands from the user are also transmitted to enddevices via down-link. Similar to gateways in a general IoTframework, BIoT gateways depend on the type of connectivitytechnology and/or device types being used, since some deviceswill connect directly to the BIoT platform. Examples of BIoTgateways include protocol conversion gateway, field gateway,and edge computing gateway where the latter can also performcertain functions defined by upper layers such as data analyticand AI.
Layer 1: Endpoint.
In IoT, there is a vast variety of enddevices ranging from personal devices such as mobile phonesand laptops to public facilities such as street lights and con-nected cars. The endpoint in BIoT is a subset of IoT devices,and the commonly seen end devices include personal wearabledevices, smart sensors (e.g., smoke detector), and smart meters(e.g., gas meter and water meter). These embedded devicesposses the capability of monitoring and collecting data fromambient environment. The types of end devices in a BIoTsystem depends on the specific requirement of the solution.III. BI O T: C
URRENT C HALLENGES
Below, we summarise the challenges faced by current BIoTsolutions. • Security.
Security is of utmost importance in BIoT.Ignoring security will lead to serious security issue andsubstantial economic loss.So, security should be the toppriority of a BIoT solution. • Heterogeneity.
In the context of smart building, the inher-ent heterogeneity of devices, networks and services makesefficient data management challenging. Moreover, theinteroperability of devices and platforms is also importantto facilitate seamless data exchange. To achieve this goal,we need a backbone network that can interconnect allheterogeneous devices such that the associated data canbe accessed and exchanged seamlessly. • Scalability.
The assets and devices in a smart buildingare constantly evolving, and their number is also rapidlyincreasing. The BIoT solution, therefore, should have the capability to handle the growing number of devices anddata. • Coverage.
BIoT requires a two-way communicationsnetwork that can connect all the sensors, controllersand actuators in the building. However, traditional com-munication technologies either suffer from short com-munication range (e.g., ZigBee, Bluetooth) or requirehigh power consumption (e.g., Wi-Fi, 4G, 5G). Thus,they are not suitable for future BIoT solutions wherethe smart sensors and objects are limited by their size,battery and processing ability. Moreover, the complexcommunication conditions in buildings due to concreteand steel structures and potential interference with theWi-Fi networks installed by occupants also makes itchallenging to achieve comprehensive coverage withinthe building, especially in basements and car parks. • Deployment/Maintenance Cost.
BIoT is traditionallyexpensive, complex, and requires customised installation,programming, and maintenance. Properly installed andconnected IoT products can overcome the capital barri-ers of installing new devices and sensors. Therefore, adesirable BIoT solution should be cost-effective by usingexisting facilities or quick-to-install products.Because BIoT is a part of a wider IoT ecosystem, althoughthe above challenges are specific to BIoT, they also apply tothe general IoT system. Moreover, after we map the abovechallenges to the five layer BIoT framework, we have twofindings. First, security is indeed the most important challengebecause attackers can launch attack from each layer. Forexample, in Layer 3 connectivity, it is known that thereare various types of attacks in a wireless network such aseavesdropping attack and Man-in-The-Middle (MITIM) attack.In Layer 1 endpoint, attackers can perform physical attackto breach the end device. Second, a low-cost ubiquitous andscalable backbone network is the key to solve the challengesfrom Layer 1 to 3. This is right the key feature of our EMIoTsolution.IV. EMI O T: A BI O T B
ARRIER B REAKING S OLUTION
A. System Design
As mentioned above, one of the primary challenges in BIoTis the lack of a low-cost and ubiquitous backbone network.A backbone network is imperative for BIoT because it allowsdynamic deployment of new networked electronic devices thathelp save energy and money along with greater environmentalsustainability and building efficiencies. EMIoT addresses thischallenge by building the BIoT system on top of emergencylights. The reason we adopt emergency lights is they areubiquitous facilities in any buildings, thus providing an idealbasis for a low-cost and ubiquitous wireless backbone net-work. In this way, EMIoT enables numerous in-building smartobjects to connect to a backbone network in a cost-effectiveway. Fig. 3 shows the system architecture of EMIoT. Eachemergency light in the building can be turned into a smart nodeby installing our LoRa wireless module. Upon installation, allthe nodes form a mesh network autonomously and connectto a single gateway, one of the mesh routers configured with
Fig. 3: EMIoT architecture.mobile connectivity to the Internet and communicates with thecloud. Users (e.g., building manager) can remotely monitorand control the network via the smartphone app or a website.
Cloud server.
EMIoT cloud leverages AWS located inSydney Australia. The communication between the cloud anddevices is managed by the underlying infrastructure. The cloudalso provides user interface via the web or an application.
Smart emergency lights.
Normal emergency lights canbe turned into smart modules with wireless connectivity byinstalling the EMIoT module. The EMIoT module consists ofSTM32 ARM-Cortex MCU and SemTech SX1272 radio chip(LoRa transceiver). The gateway uses the same hardware butit includes a 4G modem to relay the communication betweenthe cloud and the network. The communication between thegateway and cloud uses a highly secure AWS IoT solution.
LoRa mesh network.
EMIoT ensures widespread con-nectivity in a smart building by using LoRa communicationtechnology. LoRa offers lower bandwidth, but has low powerconsumption and a higher penetration capability, which en-sures the coverage of the entire building. It can meet thelow data transmission requirement of smart objects in thebuilding such as smart meters. The wireless spectrum of LoRauses sub Mega-hertz range, which is within the Industrial,Scientific and Medical (ISM) frequencies and thus free touse without any license fee. The default network structureof LoRa is a star network where all the nodes connect toa gateway directly. However, this is problematic in buildingsas there are often blind spots due to concrete walls/floors,interference from home Wi-Fi and equipments within build-ings etc. Therefore, we design a novel LoRa mesh networkprotocol, where any LoRA node can connect to the samegateway via multiple hops. The designed LoRa mesh protocolis built on top of Low-Power and Lossy Networks (RPL)communication protocol [6], where devices form a cooperativerelaying network towards the most efficient network topology.RPL is based on IPv6 address and we optimise RPL in terms of duty cycle and parameters in transmission and routing tomake it suitable for LoRa physical layer. The designed LoRamesh network presents a self-healing capability that devicesmaintain the most efficient network topology according to thecurrent environment.
Over-The-Air (OTA) programming.
Wireless code dis-semination is a fundamental function for IoT configurationmanagement within a building as the IoT devices can beupdated ”in-situ” without requiring physical handling, thussaving manual labour costs and extended operational dis-ruptions. In EMIoT, we designed a multicast-based OTAapproach considering the low-bandwidth and the large numberof devices. After a user uploads the new firmware image onthe web UI, the gateway in the building receives the OTAcommand from the cloud. Then gateway multicasts a series ofOTA packets to all the nodes in the LoRa network. After thepropagation phase, devices request missing packets until theyform a complete firmware image to update. A crucial featureof our OTA scheme is that it can complete software updatewithout interrupting regular operation of the emergency lightwhile supporting seamless safety-critical features.
Open network.
Once the EMIoT network is installed in thebuilding premise, the system opens the backbone network toother smart devices such as water meters, smoke alarms, andpower consumption monitoring nodes. Any device compatiblewith our protocol can join the network and have Internetconnectivity resulting in a truly smart building. The smartbuilding can be a part of a large city/nation-wide IoT network.To enable the open smart building network, EMIoT leveragesBLE communication. Any device with BLE capability canjoin EMIoT network and connect to the cloud. BLE modulesare low price (around $1 ) but feature powerful standardisedcommunication. It is also possible to provide other link-layerconnectivity for devices by adding corresponding communi-cation modules (e.g., ZigBee, RFID) to our mesh nodes. Network security.
Since security is a crucial concern inthe IoT field, EMIoT leverages AWS and their MQ TelemetryTransport (MQTT) IoT services. AWS MQTT presents thestate-of-the-art security features with the highest level ofreliability such as device authentication, authorisation and dataprotection in the cloud. This guarantees the gateway-cloudconnection security. For LoRa-Mesh security, we use highlysecure methods such as Advanced Security Standard (AES)128-bits encryption. The security of the open BIoT networkis guaranteed by the BLE security standard.
B. How EMIoT Addresses the Challenges
Below, we briefly explain how EMIoT breaks the currentbarriers mentioned int he last section. • Coverage.
Instead of installing new LoRa devices,EMIoT transforms existing emergency lights into meshedwireless modules to ensure connectivity across the build-ing and thereby remove any dark spots or dead zones.With the strong penetrability of LoRa and ubiquity ofemergency lights, EMIoT breaks the barrier of coverage,as no Access Points (APs) or cabling is required. • Cost.
Since EMIoT uses emergency lights that alreadyexist in all the buildings to double up and form abackbone network, the upfront investment cost is low. • Heterogeneity and Scalability.
EMIoT extends connec-tivity to other IoT networks and devices through Blue-tooth Low Energy (BLE). Any smart objects equippedwith BLE modules in the building can easily connectto the EMIoT network via a nearby emergency light.The EMIoT network can support a large number ofheterogeneous devices because each emergency light actsas a smart wireless router. Moreover, we design a LoRa-based mesh protocol for EMIoT, which can supportlarge number of end devices. Therefore, the problem ofheterogeneity and scalability is also solved.V. U SE C ASE AND L ESSONS L EARNT
A. Use Case
So far, we have deployed the EMIoT system in more than50 buildings of different types including residential buildings,shopping centres, warehouses and factories in Sydney Aus-tralia. In this paper, we use our deployment in a residentialbuilding located in Carlingford Sydney as a case study toshow its performance. This building complex has three in-dependent blocks—namely, A, B and C which share a three-level underground car park. The size of this building complexis about × × m and it has ten levels in total. Wedeployed 69 emergency lights and two gateways (also anemergency light)in this building and tested the performance ofEMIoT in six months’ time. The floor plan and the locationsof emergency lights are shown in Fig. 4. B. Results
We test the performance of EMIoT by using one gatewayand two gateways, respectively. The locations of gateways aremarked in Fig. 4. We find that one gateway can already coverall the devices in a building which demonstrate the feasibilityof our LoRa mesh network. Each gateway is connected toour Amazon server via cellular network. We collected sixmonths’ data to analyse its performance. Overall, the networkcan achieve . packet reception rate (PRR) with onegateway and . PRR with two gateways. Due to spacelimitation, we only plot the distribution of PRR using twogateways in Fig. 5(a). As shown in Fig. 5(b), over ofthe emergency lights can be connected to the gateway withintwo hops, and the mean path length is 1.7 hops with twogateways. The system has been running successfully over twoyears which demonstrates its stability and robustness. We alsotest the performance of OTA and find that it takes about 7hours to update a 125KB image for these emergency lights.If one emergency light runs into malfunction, the connectedemergency lights can find links to gateway quickly whichdemonstrates the strong self-healing capability of our LoRamesh network. The detailed performance of EMIoT can befound in our prior work [7]. Fig. 4: Floor plan. (a) Packet reception rate(b) Path length
Fig. 5: Evaluation results (using two gateways).
C. Lessons
During field study and deployment, the lessons learnt aredetailed below. • Limitation of LoRaWAN.
The prominent communica-tion protocol for LoRa is LoRaWAN which defines theMAC layer operations. LoRaWAN adopts star topologyin which all the LoRa end devices are connected to agateway. Then the gateway transmits data to a serverusing either Ethernet or wireless communication tech-nologies such as 4G and Wi-Fi. However, in our fieldstudy, we found that if the gateway and LoRa emergencylight are separated by more than seven floors then wesee a remarkable decrease in packet delivery rate. Thelimitation of LoRaWAN is also discussed in other stud-ies [8]–[11]. Therefore, the performance of LoRa is notas reliable as stated by the chip vendors. Additionally,in a one-hop network the location of the gateway shouldbe carefully considered. A common practice is to installthe gateway on the rooftop so it has better connectivity toremote server. This manner, however, will reduce the linkquality between gateway and end devices installed in thebuilding. Therefore, there is a trade-off between gateway-server connectivity and gateway-end device connectivity.EMIoT do not have such a problem because it uses LoRamesh network: if a node cannot connect with gatewaydirectly, it can find a link to gateway via multiple hops.So we can put gateway anywhere as long as it has stableconnections to the cloud. • Complexity of environment.
Basements and car parksare known to be challenging environments for wirelesscommunication due to high path loss and dynamic chan-nel conditions [12], [13]. We found that the path losschanges greatly even when we move a short distanceon the same level. Our previous studies also revealedthat the packet delivery rate varies remarkably at dif-ferent locations of the same level of an undergroundparking [7], [14]. Consequently, most devices in theunderground parking require three hops to reach thegateway, which means only mesh topology can cover thebasement and car park properly. Another observation isthat even buildings with similar layout lead to differentnetwork typologies. We believe it is mainly due to thedifferences in building materials. Another finding is thatthe walls offer better LoRa signal penetration capabilitythan floors. This is shown in our topology analysis in [7]that the parents of some devices are located in anotherblock rather than devices on the upper and lower floorseven though they may be physically closer.VI. D
ISCUSSION
There is no single definition for a smart building and differ-ent buildings have distinct requirements. Some buildings aimsto reduce energy consumption and upfront cost, while othersmay strive to improve resident satisfaction and operationalefficiency. For example, in 2016, Intel created its first IoT-enabled smart building in Bangalore, India with the aim toreducing resource usage, improving operational efficiency, and increasing occupant comfort [2]. Different requirements leadsto different design principles and system structures. Moreover,the definition and functionalities of a smart building willalso be continuously evolving with time. Clearly, EMIoT isnot a solution that can meet the requirements of any BIoTsystem. With this in mind, we discuss the advantages anddisadvantages of EMIoT in this section.The goal of EMIoT is to provide a uniform backbonenetwork for low-power and low data rate objects in a smartbuilding in a low cost way. The benefits of EMIoT are detailedbelow. • Uniform Backbone Network.
Many buildings have acombination of proprietary systems that do not talk toeach other. EMIoT addresses this problem by buildingan uniform backbone network that is ubiquitous in thewhole building. Any third party sensors, actuators andmeters can be connected to EMIoT network. • Low Cost.
The installation/maintenance cost can begreatly reduced, as existing emergency lights with powersupply are utilised as backbone by replacing the con-trol module. Even though cable-based systems providereliable and high bandwidth, they require cable instal-lation and maintenance, which costs a lot of effort andinvestment. In contrast, our system uses meshed LoRawireless communication technology which features lowpower communication and strong penetration capability.No additional equipment is necessary in the building asthe gateway possesses independent 4G mobile connec-tion. • Full Building Coverage.
As emergency lights are ubiq-uitous in any building by law for safety, they are widelydistributed. Thus, EMIoT can provide the full networkcoverage to realise ubiquitous connectivity. • Environmental friendly.
Eco-friendly smart building so-lutions are imperative as buildings consumes more than50 % of the electricity load in the world. In Australia,up to of CO2 emissions is attributed to energyconsumption of buildings. EMIoT enables large-scaleenergy-output monitoring and intelligent actuation insmart buildings which will reduce energy consumptionand greenhouse gas emissions significantly.In EMIoT, the ubiquitous communication is achieved byubiquitous emergency lights and LoRa which has strongpenetration communication ability. The emergency lights canbe replaced by other mandatory safety equipment installedin buildings such as smoke detectors. The other LPWANcommunication technologies such as NB-IoT can also be usedto replace LoRa. But in our solution, the advantage of LoRaover NB-IoT is that we can set up and manage our ownnetwork (i.e., one gateway for one building) while NB-IoTis dependent on cellular network coverage.Despite the advantages above, EMIoT is not a mast keyto any smart building solution. The application of EMIoT islimited by its low data rate. The communication technologyused in EMIoT is LoRa which is considered to be the futurewireless communication standard for IoT. However, the longrange of LoRa is achieved by sacrificing bandwidth and data rate. Compared to legacy communication technologies such asWi-Fi and ZigBee whose bandwidth is in the order of Kbpsand Mbps, the bandwidth of LoRa only varies from severalhundreds of bps to several Kbps depending on parametersetting. The limited bandwidth available in LoRa makes itunsuitable for high data rate applications such as camerasurveillance and file transferring. Therefore, EMIoT is onlysuitable for application scenarios that require low data outputsuch as smart meters.VII. C ONCLUSION
BIoT is an an important component of future smart buildingsystems since it is closely related to people’s daily lives. Inthis paper, we present a novel IoT networking solution namedEMIoT. EMIoT is built on top of ubiquitous emergency lightsfor cost effectiveness and ease of deployment. With our novelLoRa mesh network, EMIoT achieves ubiquitous connectivitythat can server as a backbone network for smart objects inthe building. Our deployment in Sydney serves as an exampleto demonstrate its performance over two years. We also sharesome hands on experience from our deployment. Currently,EMIoT has been deployed in more than 50 buildings in Sydneyand we are working closely with our partners to bring it intomany new types of buildings. We hope that our work canprovide new ideas, insights and inspirations for practitionersto facilitate the development of BIoT.A
CKNOWLEDGEMENTS
This research was supported by Australian Research Coun-cil Linkage Project LP160101260.R
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Weitao Xu (GS’16-M’17) is currently an Assistant Professor at the Depart-ment of Computer Science, City University of Hong Kong. He received hisPhD degree from the University of Queensland in 2017.
Jin Zhang (GS’14) is currently a postdoc at Shenzhen Institutes of AdvancedTechnology Chinese Academy of Sciences. He received PhD from theUniversity of New South Wales (UNSW) in 2017.
Jun Young Kim (GS’14) received PhD from the University of New SouthWales (UNSW) in 2017. His main research consists of security and manage-ment of the Internet of Things (IoT). He is now leading the R & D team at theWBS technology in Sydney to develop a smart building service.
Walter Huang is the director of WBS Technology Australia. WBS Technol-ogy is recognised as Australia’s leading manufacturer of high quality LEDEmergency Lighting, LED Exit Signs and LED Lighting Systems.
Salil S. Kanhere is currently a Professor with the School of ComputerScience and Engineering, University of New South Wales. His current researchinterests include pervasive computing, crowdsourcing, and sensor networks.
Sanjay K. Jha (SM’08) is a Professor, head of NetSyS and director ofCySPri Laboratory at the School of Computer Science and Engineering atthe University of New South Wales.
Wen Hu (S’04M’06SM’12) is an Associate Professor with the School ofComputer Science and Engineering, the University of New South Wales. Hisresearch interests include sensor networks, IoT and low power communica-tions.