Today’s connected-home platforms have come a long way from their roots as simple security systems, evolving to automate everything from our thermostats to our kitchen appliances. Now it’s time to also evolve the way we manage access to our connected homes, which is why we’re working on an approach that uses blockchain technology to give our customers unique control and peace of mind.

By 2020, Americans will have an average of 50 Wi-Fi-connected devices in their homes. In such ultra-connected homes, there are any number of situations in which we will want friends, or family members or guests to be able to control some features of our connected homes, without giving them access to everything.

For instance, you may want to let your kids unlock your home’s smart doors using an app on their phones, but not give them the ability to monitor your security cameras, or remotely change the thermostat. Or perhaps you want to make it easy for your neighbor to get into your garage while you’re away on vacation, but not give them access to your whole house.

Today’s smart home systems don’t have a way to provide that sort of pinpoint access. We can give our kids access to the whole system via an app, or keep the control to ourselves, but not pick and choose exactly what devices and services we want to make available or keep off limits. 

Working together with Comcast Labs, our information security team joined with Sridhar Solur’s digital home engineering team to improve that experience, and what we came up with was a new application for blockchains that puts the user at the center of the digital home experience.

Blockchains may be most commonly associated with cryptocurrencies, but the underlying technology provides a powerful, flexible and secure platform that can support many types of sensitive transactions where privacy and reliability are critical.

The approach we’ve developed puts customers in control of their digital homes by providing them a tool to easily grant, revoke and tailor access to any IoT device in a way that is safe, private and highly resistant to tampering.

The model we developed will allow us to create a unique digital identity for each customer, which will be associated with a permission-based blockchain ledger or “trunk”. Customers can then associate individual IoT devices –“leaves” – with their ledger and then set and revoke permissions as they see fit.

To give an example of how that might work, you may ask a neighbor to keep an eye on your dog when you have a long day away from home. To make that easy, you make a few taps on your phone to provide your neighbor temporary access to your living room camera and back-door lock. When you get back home, you make a couple more taps and turn off your neighbor’s access as easily as you turned it on. 

The beauty of this approach is that because blockchains are decentralized you can grant and revoke access dynamically from anywhere in a secure way.

We are excited to share more about the technology as we expand testing and move toward deploying it for our connected home customers. With our recent move to expand home automation services to more than 15 million customers at no additional cost, this has the potential to be yet another powerful tool to create connected home experiences that are simple, safe and secure. 

(This Comcast Labs project would not have been possible without the commitment of Asad Haque, Director, Information Security).