Popular IoT Protocols 2019: An Overview & Comparison [updated]

It’s time to peek behind the scenes of connected things and talk about the protocols used in IoT.

The IoT protocol world is complex – legacy protocols, emerging technologies, different layering methodologies and many use cases. There are hundreds of protocols, too many to compare them all.

In 2017, when we first wrote this post we focused on data transmitting protocols, comparing 5 of the most used IoT protocols.

In our 2019 update, we’re adding IoT communications protocols as well. Why now? It’s become clear that cellular networks, 4G and the upcoming 5G protocols, in particular, are not best suited for mass adoption of IoT. Leaner communication protocols that enable low-cost modules and consume less power are critical for IoT sensors.

Communication Protocols

Today’s cellular networks are designed for high-bandwidth mobile communication for high-resolution smartphone screens. They do an excellent job but aren’t overly concerned with power consumption, or the cost of phone’s communication components, which can reach as high as $35 for a 4G module.

In contrast, most IoT devices require very little bandwidth, as low as a few kilobytes of data, a few times a day. They’re field deployed and hard to replace, so long battery life is critical. In addition, lower component costs than those offered by cellular comms are a must for large scale deployments.

Enter communication protocols designed for IoT. LPWAN (Low Power Wide Area Network) protocols define the network & physical layer access in the TCP/IP model.

Protocol	Description	Advantages	Disadvantages
NB-IoT (Narrow Band IoT): Nokia+Ericsson	3GPP is still defining the NB-IoT standard, which probably won’t be finalized until 2023. Nokia and Ericsson are proposing a lower power version of 4G.	Interoperable with existing 4G devices and networks Encrypted	Power is not very low Moderately expensive
NB-IoT (Narrow Band IoT): Huawei+Vodafone	Huawei+Vodafone are championing a clean slate approach to NB-IoT that could result in very low power & low-cost cellular components.	Very low power that can extend IoT device battery life May end up costing as low as $1 per cellular component Encrypted	Requires a dedicated band for deployment, which cellular operators don’t like Not interoperable with any existing infrastructure
LoRaWAN	A multi-vendor eco-system for low power & low bandwidth communication modules.	Anyone can create their own private LoRa network with a radius of 5K Included in the Raspberry Pi community Symmetric link is good for bidirectional communications Encrypted	Very low data rates, may be too low for some applications Overlapping LoraWAN networks interfere with one another Limited to 5-10 km distance with line of sight Not ideal for moving applications
Sigfox	A low power, low bandwidth communication protocol developed by a private French company	Lowest bandwidth costs Lowest power requirements	Only limited deployment, mostly in Europe Limited to where Sigfox has deployed a network Constrained base station to endpoint comms Not suitable for mobility applications No encryption

 

Data Transmission Protocols

Before we dig in, let’s go over a couple of basic terms:

1. Overhead- an excess or indirect computation time, memory, bandwidth, or other resources required to attain a specific goal.
2. Latency – Delay between the stimulation and response

There are protocols we aren’t discussing today but will occasionally show up in IoT applications:

1. HTTP – the foundational protocol of the WWW but with limited use for IoT due to, it not being able to support bi-directional communication, and its high overhead.
2. TCP & UDP – Old kids on the block. Most of the IoT protocols based on these two and add IoT-specific features on top of the basic protocols.

 

Protocol	Advantages	Disadvantages
MQTT	Easy toimplement Useful for connections with remote location Small code footprint Lightweight Asymmetric client-server relationship	No error-handling Hard to add extensions Basic message queuing implementations Doesn’t address connection security
CoAP	Multicast support Low overhead Minimizing the complexity of mapping with HTTP Communication models flexibility Low latency	Doesn’t enable communication level security Few existing libraries and solution support
AMQP	Complex message queuing implementations ISO standard High routing reliability and security Easily extensible Symmetric client-server relationship	Larger package size than other protocols Doesn’t support Last Value Queue (LVQ)
Websocket	Simplifies the web communication and co-network compatibility Connection management	Specific  hardware  requirements No useful open source implementations targeted at embedded systems
XMPP-IoT	Real time Low latency Easily understandable Easily extensible Any XMPP server may be isolated	XML-based  protocol,  heavy data overhead Not suitable for embedded IoT applications

Our platform can handle any of these communication and data transmission protocols, as well as many others. We use a protocol and data gateway that can ingest data in any protocol, current or future, and standardizes this for communication within the Axonize cloud. Contact us to learn more.