By Steve Dunn June 2020 

In late 2016 whilst we were attending an IoT accelerator in Venice, Italy, we received an email from Vodafone asking us if we were interested in exploring their new NarrowBand Internet of Things (NB IoT) technology to see if we could use it in our Smartlock Software Development Kit (SDK). Vodafone had seen our SDK mentioned in a European Commission (EC) newsletter (we had just received a EC R&D Grant). 

Video: Building our NB IoT smartlock prototype in the Vodafone NB IoT lab in 2017

The first thing that excited us about NB IoT was the high levels of security built into it. The other thing NB IoT offered, which our SDK with One Time Password Technology (OTP) and Near Field Communication (NFC) Technology didn’t have, was the ability to directly communicate with the locks online in real-time.  OTP is a technology commonly used by banks in online banking, and as a security feature with website account passwords. In short, OTP algorithms enabled us to essentially pre-program smartlocks in the lab with millions of unique identifiers/codes for specific future dates and times, which could be accessed from software and apps when required and used as time-limited digital keys. But OTP didn’t enable live interactions with the lock. In addition to improving the security in our smartlock SDK, NB IoT also meant we could offer added features such as;

  • remote unlocking from apps and software (OTP/NFC enabled us to only share the digital key with someone’s phone, not directly unlock the door from anywhere)

  • canceling digital keys at anytime (OTP/NFC meant you had to physically visit the lock to cancel the digital key with an override code).  

We also noticed that by bringing the lock online with NB IoT we could offer a more interoperable solution - that is better interfaces with other hardware and software. For example, adding a motion detector to the lock (connected by NB IoT) could easily be set up and monitored in the same software we use to manage the smart locks.


We spent the first part of 2017 in the Vodafone NB IoT lab at their Headquarters in Newbury UK exploring their new NB IoT technology. Our team travelled back and forth from the IoT accelerator in Venice to Newbury on a weekly basis, only a 45 minute flight, and when the IoT accelerator finished in March, we moved into the lab and nearby accommodation full-time. In the NB IoT lab, we were grateful to receive full support from Vodafone. We worked alongside Vodafone engineers daily and we had full access to all of their cutting-edge prototyping and electronic equipment.  We also had support from Vodafone partner company engineers (such as from Taoglas Antenna company and NB IoT chipsets manufacturer U-Blox) who often frequented the lab.

By June 2017, we finished building our first prototype.  We were excited to achieve a world first by successfully sending the first ever unlock command over the NB IoT network to unlock a lock. Previously the NB IoT network had been mostly used by utility companies for smart electricity meters, and smart water meters, so Vodafone were as excited as us to see a new functioning application for NB IoT. Over the last couple of years, Vodafone like many other telecommunication companies in Europe, had invested heavily in developing NB IoT and they were keen to see how far the technology could go. NB IoT is a software upgrade on existing mobile network towers so it doesn’t involve the need to install new equipment like 5G, however that’s not to say that significant investment had not gone into developing this technology. One of IoT managers at Vodafone had this to say about our achievement in a Vodafone blog;


“Solutions like this with an intelligent lock, highlight the multiple applications offered by our NB-IoT network, which opens up a new world of possibilities for IoT projects like this one and it allows the market to bring innovative solutions that bring efficiency and security to customers”


In July, Vodafone invited us to demonstrate our prototype at their Innovation day at their Headquarters. We performed hundreds of successful demos that day, and got the interest of a number of senior IoT managers, including being able to demo to the CTO and COO of Vodafone. Our aim was to convince everyone of how appropriate NB IoT was for use with smartlocks. Many officers were unsure about the high latency of some NB IoT products (the time it takes for communications to go from apps and over the NB IoT network to the devices. Many officers in Vodafone thought NB IoT may not be appropriate for access control and smart locks as there could be long latencies of a few seconds. But we proved them wrong with a low latency of 1-3 seconds.

Image above and right: NB IoT smart padlock MVP 2018

We worked hard on the latency issue early on in our product development. For example we had to try sending the lock commands into several different communication ports over a couple of week period (apparently there are thousands of ports where signals can go in the mobile network, and some are more optimised than others for certain features, such as voice, apps, texts etc)


We took a short summer break when the lab closed and returned more determined than ever to build the next iteration of our smartlock - our Minimal Viable Product (MVP).  For the prototype we were concerned about simply using the NB IoT network for sending unlock commands to the lock, and extracting the live audit back from the lock. But for our MVP we wanted to introduce some new opening methods in coordination with NB IoT.


The two opening methods we began working on was with NFC technology and time-sensitive PIN. The idea was to use the NB IoT network once to program the locks to accept unique digital keys from certain users for certain periods, as part of a batch of locks, when the digital keys were first generated in our software and apps. The locks CPU would then remember the unique digital key details, so users could unlock locally, and not have to go over the NB IoT network everytime they wanted to unlock. This is typically how wired keycards in offices and hotels worked – that is, the receptionist logs into software when you first check in to a hotel, or when you arrive at a large office building as a visitor, and generates you a keycard (with a unique ID). The keycard software communicates over the wiring to the particular room that you are to stay in (or visit), to say please accept this keycard only for this set period of time. The locks don’t need to go back to the computer at the reception desk everytime a card is presented at the door and ask ‘is this keycard acceptable’ – the lock CPU simply remembers that this is an acceptable keycard at this time (lock has internal clock), and other keycards are not acceptable. 








We spent the latter half of 2017 further refining and optimising our product. A considerable amount of testing time was devoted to interfacing to a specially built NB IoT Device Management platform. This platform interfaces meant we could better track data flowing throughout the system, increase security (such as adding IP security and a private VPN), and offer a more reliable solution for multiple lock management. This platform also meant we could use Vodafone SIM’s inside the lock and plug into Vodafone’s Global Data Service Platform software for managing connectivity on their network or their partners network anywhere in the world. We also began preparing marketing and support material such as manuals, instruction sheets and software explainer videos. We also ran various sales and marketing training sessions in Madrid with Vodafone sales teams. Around this time we also attended a number of conferences and trade shows to demo our product, including at the Mobile Broadband World Forum in London and an IoT conference in Iceland (see images below).















In early 2018, we sent some of our locks to another lab in Germany to begin NB IoT certification testing. It was a condition that all NB IoT device partners pass certification before they take their product to market. After over 5000 unlock commands in the lab, and a lot of back-end tweaking and firmware updates, we reached 99% successful remote unlocking over the NB IoT network in 1-3 seconds (1% in 3-10 seconds). We also further optimized our antenna for better signal strength and determined the exact workable NB IoT signal strength levels (this information was useful to supply to Vodafone and other telco's to ensure the signal strength at local towers was set at a minimum level to make our smartlock operable).

Finally in March 2018, we received the coveted NB IoT market ready certification. The next step was to replicate these same lab tests results in the field with a pilot. Vodafone asked all device partners to pilot test in Spain, as it was the country with the most reliable and extensive NB IoT network at the time. Spain is commonly used by Vodafone as a testing bed for new technologies (for example it was one of the first countries in the world to get a commercial 5G network switched on in mid 2019. 


Vodafone introduced us to a system integrator/re-seller in Malaga Spain (a company with experience developing IoT products, and a re-seller of access control products) and with their support we began pilot tests in their offices.


By April we finished the field pilot tests, with several firmware upgrades/configurations to our back-end to integrate with the local Spanish NB IoT network.


We also polished our API’s some more and provided them to our system integrator partners in Spain, so they could customerise some access control management software specifically for Vodafone Spain salespeople.


At this time, we were determined to see if our product worked on other NB IoT networks around the world, so we made arrangements with Vodafone Australia, Telia Norway, and Duetche Telekom in Poland, and successfully connected our product to their NB IoT networks.  We also demonstrated our product at Mobile World Congress (see below right) and our video was featured on Vodafone's home page. This was part of Vodafone's marketing drive to their existing enterprise customers.


The final test that Vodafone supported us to pass before we were ready to sell our product was what we called ‘monkey crash tests’. That is, we had to deliberately try to cause our system to crash as if we were 'monkeys playing with it'. These tests were about making the product more robust and user friendly. During the monkey crash tests, we identified a couple of user behavioral issues, and improved the UX/UI to the apps and software.   


We completed the monkey crash tests in June 2018 and after one and half years of building and testing, we we’re finally ready to start manufacturing the world’s first complete end-to-end NB IoT smart access control solution and take it to the market.


We’ve began negotiations with manufacturing partners, and designed a new iteration of product in readiness for the commercial release.  

In early 2019, we had the first 100 locks manufactured and shipped off to our system integrator/re-seller partners in Spain who installed 5-20 products in 3 hotels, 2 office buildings, a bank, a University, and a football club in Madrid. Following a couple of months of field trials, and constant tweaking and optimising, we finally shipped 1000 units off to our Spainish re-sellers, where they were sold to various customers for use in commercial buildings in Spain.  See the images below of the locks being prepared for shipping.


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