Smart Homes are among the most enticing areas of the Internet of Things that are in high demand. The system conveniently allows users to control their home appliances from anywhere in the world using internet connectivity and have them automate their work based on your preference as if you were physically at home.
Smart devices are at least ten times more expensive than regular ones, like the smart bulb. With higher price tags, many customers are rather reluctant to buy them. Let’s amplify this into something that you really would like to have, and the decisions that you are faced with.
In this article, we highlight the protocols (the language) needed for your Smart Home to function well to your specific needs. You already know 2 protocols very well. WiFi and Bluetooth. And yes, there are more protocols that we introduce here for your Smart Home requirements. Great! So, which protocol do you need?
We kick off with Z-Wave:
In basic terms, Z-Wave is a network design that allows reliable transmissions of short messages from a control unit to other nodes. An interoperable, wireless communication language designed for use in residential and commercial environments, the standard for control and monitoring applications. It is recognized as the world market leader in wireless control, with more than 70 million products sold worldwide and over 450 manufacturers supporting it.
Z-Wave devices to be either slaves or controllers. The slave responds to requests from the controller and executes commands. The maximum number of nodes in the network is 232. It also offers a maximum range of 30 meters, resulting in the need to add more devices to increase coverage. As a result of adding more repeaters and routers, the total cost of operating the network increases. A slower data transmission rate of 100 kbps sounds quite, primitive really. But, slower speeds are usually used for monitoring and controlling functions. It is necessary to have knowledge of technology in order to protect it from unauthorized users. Since Z-wave uses radio frequency (RF), between 868 and 928 MHz (region dependant) and it can be accessed from any location.
With a vast compatibility range, all smart home devices can connect to each other and communicate. Even devices outside the router's range can connect to the network. To do this, the mesh-like configuration will require a large number of devices to ensure reliable operation and with this setup, expect a high latency.
The cost of Z-wave chips is typically higher since they are manufactured by a single manufacturer. Even though there are some weaknesses attached to this option, it is widely accepted and a very reliable solution when configured properly. If implemented well, it appears to be a very solid solution and an excellent option in the home products arena.
So, let’s sum this up for the Z-Wave protocol:
Cons
- Node limitations
- Signal transmission limitations
- Costly
- Communication speed
- Requires a Smart Hub
- More devices are required to cover wider areas
- Closed system - one manufacturer.
- Battery intensive on all devices
Pros
- Excellent device communication between 15 and 30 meters from each other
- Flexible to ever-changing products
- Operates at 908.42 MHz - efficient without any 2.4Gz or WiFi interference
- Suitable for inside use, at home, or a small office
- Secure using AES-128 encryption - easy setup
- Solid communication speeds of up to 100kbps between devices
Let’s introduce the second protocol on our list - ZigBee:
This is a wireless standard for low-power, low-rate communication designed for interoperability
and encompasses devices from different manufacturers. It is an open-source protocol stack that any company or developer can use.
Through the coordinator, Zigbee transmits messages to the router, which then forwards them to the end device capable of performing the task. Because of its short-range capabilities, this technology can be used for short-range wireless communication.
ZigBee has three stack profiles: ZigBee, ZigBee PRO, and ZigBee IP. ZigBee PRO comparing to ZigBee is optimized for larger networks, but it is more expensive and requires more memory
Three types of ZigBee networks:
- Star Topology - simplest and least expensive.
All device endpoints are directly linked to the coordinator, and there are no routers. If the coordinator fails, the whole network will crash, and there will be no one to instruct the end devices. Similarly, star networks are also limited by the ranges of the coordinators and are therefore only suitable for smallnetworks made up of just a few devices.
2.Mesh Topology
There are nodes connecting to neighboring nodes, except end devices that are only connected to their parent, the router. Using the coordinator, the routers closest to the coordinator are connected to the other routers closest to them. As a result, some routers might have connections to the coordinator and one other router, while others might be connected to as many as four routers, depending on the size of the network. Communication between devices involves hops from one to another, taking the shortest possible route. Even if a particular node fails, the network can simply re-route the message using a different path if the node fails. The process is known as "self-healing". This topology is optimal for smart homes since these homes usually have more devices than a star topology can accommodate.
- Tree Topology
With the largest difference being the fact that the routers aren't interconnected, tree topologies are very similar to mesh topologies. Essentially, routers and coordinators are connected, but these connections are as broad as they will go. The coordinator and routers do not interact with one another. Alternatively, “cluster tree” networks allow routers to communicate with one another, thus expanding the range of the network.
ZigBee works on the same principles as Z-Wave, one universal language for all the different smart home products, and setting this protocol up is quite simple, really. Unfortunately, there is no guarantee that if you buy a device from one manufacturer that it will work with another device from another manufacturer. When trying to set up your Smart Home effortlessly, it can be a bit daunting because we know, in general, everything should, well, just work!
The process of setting up the network is pretty straightforward. Using a remote control, you can also monitor and control your home appliances. By replacing existing devices that use infrared technology, it will eliminate the need for existing devices. Since only lithium batteries are used, this will reduce the cost of battery replacement. In addition to its scalability, the network can accommodate remote ZigBee end devices easily.
When it comes to ZigBee compatible smart home products, it is extremely limited. The data transmission rate is also lower than that of Z-Wave. Owners of ZigBee-compliant devices must know how to operate them. In certain locations, 9002 MHz to 928 MHz and 868 MHz to 868.6 MHz are the three unlicensed frequency bands used. There are 16 channels in the 2.4 GHz band, each of which is 5 MHz, 10 channels in the 915 MHz band, and one channel in the 868 MHz band.
Besides only having a range of 10 meters, numerous disadvantages are exposed. Data speed is low, and complexity is low. Despite this, this standard supports more nodes than Z-Wave - a total of 65000 nodes. We believe this is way too much to ask from any smart house; however, it is not impossible.
Low network stability, high maintenance costs, and a lack of a comprehensive solution are also some of its disadvantages. It lacks the same security level as its WiFi equivalent. A ZigBee Smart Home can only be controlled from inside the home due to its limitations. It may be understated to assume that Z-Wave is more expensive than its counterparts. Continuous replacements of home products and appliances can be quite costly. Like other mesh networks, there is a downside - many devices are required for reliable operation and latency is high. Another advantage is that this protocol is already widely available and adopted, and it works as long as all of your devices are compliant. The technology can be used for many different purposes thanks to its low power use and low data transfer rate. Wireless sensor networks, home automation, industrial control systems, medical data collection, and smoke and intruder detection are some of the most common. Zigbee was developed primarily for the purpose of collecting data from buildings or controlling certain functions within them.
This is a good choice for consumers who are looking to buy low-cost products.
The technology can be used for many different purposes thanks to its low power use and low data transfer rate. Wireless sensor networks, home automation, industrial control systems, medical data collection, and smoke and intruder detection are some of the most common. Zigbee was developed primarily for the purpose of collecting data from buildings or controlling certain functions within them.
Our final protocol - 433 MHz technology - sounds a little like the Dinosaur era, doesn’t it?
We all know this one, “Where is the remote for the TV?” or any other remote! Running around looking for remotes has always kept us busy and while doing this, we missed an important feature in the movie! And some of us are on the hunt for a smartphone that can offer RF technology to create an inexpensive smart home. Let’s give it a shot!
Radiofrequency 433MHz is used for wireless communication. It’s the frequency at which household devices can transmit their signals. 433MHz is used by many companies that manufacture products with remote controls.
Now, this is a fine and affordable technology, but not the whole world runs on it.
The biggest advantage of 433 MHz technology is its overall range. This technology uses a frequency lower than Z-wave (868-928 MHz), Zigbee (2.4 GHz), and Wi-Fi (192.168 or 52.368 GHz). In other words, it is less capable of holding information but can move through walls better. This translates into a pretty impressive range of devices that can operate on 433 MHz. This is especially true for devices such as motorized blinds that send commands via 433 MHz hubs. In this case, the signal can cross numerous devices and distances at the same time over 100m away.
Despite its many advantages such as its ease of use and low cost, 433 MHz also has its share of disadvantages. The technology itself is very primitive. One-way signals are typically the norm. This means the device only sends and receives data. Furthermore, the receiver is not able to confirm commands. Unless otherwise specified, we must assume the command has been executed. Devices and sensors using 433 MHz are less reliable than those connected to Zigbee or Z-Wave.
Furthermore, devices operating at 433MHz do not build a 'mesh network'. It is like walking forward and backward whenever a button is pushed. So, we can only assume that with this protocol, you would need quite a few remote controls to create a useful smart home as well as a very small budget.
Despite mesh networking being a great technology, 433MHz devices are not compatible. Also, the amount of information sent is very limited. The bandwidth of 433.3MHz is usually limited. There is only a limited set of commands available. It might not even be possible for your roller blind to move to a certain percentage, but only up, down, and stop. It is also rare to find information about batteries or energy consumption. Even though 433MHz devices can operate on batteries, there is nowhere to watch for low batteries, so you'll have to keep an eye out.
As a final note, 433MHz devices cannot be directly connected to your smartphone. The phone you are using does not have a 433 MHz antenna. For these devices to connect and be automated, you must have a smart home hub. Nevertheless, this is also the case with high-end technologies like Zigbee and Z-Wave.
Data volume and transmission rate are among the other differences as we discovered with Z-Wave and ZigBee. Utilizing a one-way technology protocol is quite a simple protocol that allows you to control your lights, TVs, blinds, and remote doors, for example. This technology is not new but neither has it aged.
Here is a complete form for you, helps you grow your understanding of Z-Wave 、 Zigbee and433MHz
| Category | 
|
 |
433RF |
| Network config | Wireless mesh network | Wireless mesh network |
|
| Open or closed protocol standard | Closed | Open | Closed |
| Included in 2020 smart home open source standard alliance | No | Yes | No |
| Compatible with other products | Yes | Most of the time | 433 MHz device, Examples are motorized blinds from Somfy |
| Security | High (AES128 encryption) | High (AES128 encryption) | High (AES128 encryption) |
| Power usage | Low | Low | Low |
| Frequency | 908.42 MHz | 2.4 GHz | 433MHz |
| Wi-Fi interference | No | Possibly, but likely negligible | Possibly, but likely negligible |
| Max Data Rate | 100 Kbps | 250 Kbps | 3000bps |
| Range of network |
Line of sight: Up to 100+ meters (328 ft) Indoors: Up to 9 meters (30 ft) |
Line of sight: Up to 100+ meters (328 ft) Indoors: Up to 9 meters (30 ft) |
Line of sight: Up to 100+ meters (328 ft) Indoors: Up to 9 meters (30 ft) |
| Total devices supported on one network | 232 devices | 65,000 devices | add 16 devices and 64 buttons |
| Number of products on the market | 3,200 | 3,500 | |
| Number of certified products sold | 100 million | 300 million | |
| Hub required | Yes | Yes | Yes |
In a word
With the above guidance, hopefully you will be able to figure out which protocols are most important to your home. In terms of price or power, Zigbee is far ahead in two pure categories. Z-wave is the clear winner in terms of reliability, interoperability, and signal range. Of course, your decision should be entirely personal. Whatever your choice, you will have a Smart Home that you’ve never had before!