Does The Connected Home Needs Another Protocol?

  • Posted on: 21 December 2014
  • By: Patrick Oliphant

Depending on the smart appliance you buy you are also making a decision on what communication protocol you want to use.  With the growth in the Internet of Things (IoT) it is even more important because we want all of the devices in our homes to be able to communicate with each other securely.  This is on the backdrop that there are many protocols for the home at the moment.  To add to the complexity or to simplify things a new protocol 'Thread' has been introduced.

Thread is being introduced by the Thread Group which consists of Nest Labs, Freescale Semiconductor, Big Ass Fans, Yale Security, Silicon Labs, Samsung Electronics and ARM. The Thread protocol promises to be reliable, secure, need less power and will simplify connectivity.  With 6LoWPAN as its foundation, the group said IPv6 is at its core and will make IoT easier to implement into the home.

But, should we be introducing another protocol into the home, haven’t we got enough?  There is already DLNA, ZigBee, Z-Wave, 3G/4G, WiFi and Bluetooth, to name a few of the popular ones. So why spend time and money to develop a new wireless communication standard? One of the reason presented by the Thread Group, is that the connected home and IoT overall need a protocol that is built for both. Also, one of the key characteristics of IoT is that connected devices are more likely to send small pockets of data to and from many more devices something that some of today’s protocols were not designed for.

The Thread Group also pointed out that while currently available 802.15.4 networking technologies have their own advantages, each also has critical issues that prevent the promise of the Internet of Things from being realized.  These include lack of interoperability, inability to carry IPv6 communications, high power requirement that drain batteries quickly and “hub and spoke” models dependent on one device (if that device fails, the whole network goes down).

DLNA (Digital Living Network Alliance) is great plug and play solution but it is mainly focuses on interoperability between networked entertainment and media devices for personal media uses that involve images, audio and video and it is not IPv6 ready, which eliminate many other devices.

LTE 3G/4G are great, they are IPv6 ready but they are more suited for mobile broadband activities such as web browsing, video streaming and photo uploading from a smart phone.  They are a big drain on batteries, doesn’t make it optimal solution for what we are trying to achieve with the Internet of Things.

Bluetooth was developed by Nokia and introduced as Wibree in 2006, but became Bluetooth in 2010 when it merged with the original Bluetooth standard. It’s now been called Bluetooth smart. Bluetooth smart of is smaller and can run on small batteries.

In comparison to other connected home protocol Bluetooth is compatible with the most popular connected home devices such as tablets and smart phones, and use less power than WiFi.  Thus it is the chosen protocol for wearables and can now function as mesh network similar to ZigBee. It does not support IPv6 by default.

ZigBee has been an instrumental standard and protocol ushering the smart home and connected lifestyle.  ZigBee has a few things that make it a protocol of choice: It is an open standard; it uses a mesh network, meaning any new devices (nodes) join the network (such as light bulb) they can be used as a network extender. As a mesh network ZigBee can allow up to 65,000 nodes/devices to be connected, a big advantage over Bluetooth eight and WiFi 32.

Another thing is its power usage, its standby current can reach very low level and theoretically a remote control with ZigBee could last over 20 years on one coin cell battery.  This also means that ZigBee can be used in devices with no battery by using energy harvesting; available in some solutions, like Greenpeak prototype light switch.

The ZigBee protocol is not naturally IPv6 compatible and to facilitate IPv6 communication it has to be integrate with WiFi to extend connectivity to the Internet.

Z-wave protocol like ZigBee is based on 802.15 standards and also uses the mesh networking topology (with support for up to 232 nodes) and seminaries to ZigBee, with the exception that it is not open, it is licensed with Sigma Designs and can operate on their silicon receivers only. It is not IPv6 by default and focus focuses on home security as well as automation with short-range remote functions such as lighting, heating, monitoring motions, and playing an entertainment systems.

6LoWPAN is not a wireless standard but it is being used as part of the core of the new Thread protocol. What 6LoWPAN has that the others dont is that it allows IPv6 wireless traffic over devices with limited bandwidth capability.  It is hardware-agnostic and can connect any device via IPv6.

I think when you look at the arguments you can see where there are reasons for the new protocol and as Vint Cerf of Google puts it, “Existing wireless networking approaches were introduced long before the Internet of Things gained ground.  The Thread protocol takes existing technologies and combines the best parts of each to provide a better way to connect products in the home.”

Millions of existing 802.15.4 wireless devices already on the market can run Thread with just a software enhancement; no new hardware required, said the Thread Group. So how knows Thread could be the best thing to happen to wireless networking in the home.