The right communication protocol can involve the performance, scalability, reliability, and security of the application. The options include MQTT and HTTP. Yet both protocols have different requirements for communication. This understanding is essential when choosing an IoT app development company that can build secure, scalable, and reliable connected applications.
MQTT is a lightweight protocol used for the transmission of small messages, while HTTP follows a request-response model ideal for APIs, web applications and server communication.
In IoT application development, the choice of protocol will be based on factors such as devices, network, data and frequency. This article provides a comparison between MQTT and HTTP in terms of performance, applications, architecture, and security for Internet of Things app development.
MQTT is usually good for lightweight and real-time communication, while HTTP works better for API and web integration purposes.
What Are MQTT and HTTP?
MQTT and HTTP represent some popular IoT communication protocols, they each operate on a completely different communication model and serve their own purposes.
What Is MQTT?
MQTT stands for Message Queuing Telemetry Transport protocol that is a messaging protocol designed for the use with IoT devices only. MQTT for IoT follows the publish/subscribe pattern where devices interact with each other through the broker. This helps to minimize communication traffic and can work well with constraint devices.
According to the OASIS MQTT Version 5.0 specification, MQTT is designed for constrained environments where a small code footprint and efficient use of network bandwidth are important.
What Is HTTP?
HTTP (Hypertext Transfer Protocol) has a client/server design where requests are made and responses are received. HTTP for IoT is mostly applied in websites, RESTful APIs, and cloud computing services. This design of HTTP is very convenient for integration of the IoT system with Web technologies.
The IETF RFC 9110 specification defines HTTP as a stateless request/response protocol and explains how clients send requests while servers return responses.
What is the difference between MQTT and HTTP?
MQTT works on lightweight publish-subscribe message passing, while HTTP operates on request-response message passing. MQTT works best with continuous messaging of devices, while HTTP is helpful with APIs.
How MQTT Works in IoT Applications
MQTT uses the publish/subscribe messaging pattern to communicate data between IoT devices and applications. Instead of communicating directly with each other, devices send messages through an MQTT broker.
MQTT Architecture
The basic flow is:
IoT Device → MQTT Broker → IoT Application
The device that publishes data is referred to as the publisher. It publishes a message on a particular topic. The message is then received by the MQTT broker and is forwarded to the subscribers who are listening to that topic. For example, a temperature sensor can publish messages on the factory/temperature topic.
MQTT was created with connectivity between devices which may be constrained in terms of capabilities or unreliable networks. The Publish/Subscribe pattern, Topics, Quality of Service, persistence, and small message sizes make the communication very efficient. MQTT has low bandwidth requirements, making it an ideal protocol for applications sending frequent sensor measurements.
In the case of a connected device application that is always sending data from sensors, there may be fewer communications overheads using MQTT compared to always creating request-response connections.
How HTTP Works in IoT Applications
The HTTP protocol uses a request-response process to facilitate data transfer between Internet of Things devices and servers. The basic flow is:
IoT Device → HTTP Request → Server/API → Response
IoT devices initiate an HTTP request to the server or API endpoint. GET fetches data from the source, POST submits data, PUT modifies data, and DELETE deletes data. RESTful APIs generally employ these HTTP methods to facilitate connectivity between devices and backend systems.
For example, a temperature sensor can send:
POST → /api/device/temperature
The backend gets the request, processes it along with the data of the temperature, and sends back the response.
HTTP is useful for IoT when there is a requirement for API compatibility with web-based dashboard interfaces, mobile applications, cloud servers, or external service providers. HTTP is frequently used for IoT application development if devices have to interact with web-based systems.
Companies developing connected systems can use IoT app development solutions to connect the devices, REST APIs, databases, and applications using standard HTTP communication.
MQTT vs HTTP: Key Differences
While MQTT and HTTP both help connect IoT devices to applications, there is a difference in their design purposes.
| Factor | MQTT | HTTP |
| Communication model | Publish/Subscribe | Request/Response |
| Overhead | Low | Higher |
| Real-time communication | Excellent | Possible |
| Bandwidth efficiency | High | Lower |
| Persistent connection | Supported | Usually request-based |
| IoT suitability | Excellent | Good |
| Device constraints | Well suited | Less optimized |
| Web/API integration | Requires additional architecture | Excellent |
| Large-scale messaging | Strong | Depends on architecture |
| Learning curve | Moderate | Familiar to most developers |
The main difference is how they communicate. MQTT allows the device to publish data on a particular topic, and the subscribers are updated by the broker. MQTT is therefore suitable for regular sensor measurements and IoT communication.
HTTP requires the device or software to make a request and await a response. It works perfectly with REST APIs, websites, mobile applications, and cloud-based solutions.
MQTT also provides reduced communication overhead and uses the available bandwidth efficiently, making it ideal for resource-constrained IoT devices. HTTP is relatively simpler to implement within the existing web infrastructure.
Is MQTT better than HTTP for IoT?
MQTT would be a better choice for regular communication between devices and/or cloud services, whereas HTTP remains an extremely valuable choice for APIs and web services.
MQTT vs HTTP: Which Is Better for IoT?
There is no universal winner between MQTT and HTTP. The better choice depends on the device → network → data → application → scalability → security requirements of the IoT system.
MQTT is generally better when:
- Devices frequently send small messages
- Low bandwidth is important
- Network conditions are unreliable
- Real-time communication is required
- Large numbers of devices need messaging
MQTT is particularly useful for connected devices that continuously exchange lightweight data. Its publish/subscribe model and persistent connections can make frequent communication more efficient.
HTTP is generally better when:
- You need REST APIs
- Applications communicate with web services
- Third-party API integration is important
- Request-response communication is sufficient
- Existing web infrastructure is being reused
However, HTTP may be the best option if there is a need for an IoT solution to interface with Web sites, apps, or clouds.
The final decision should consider how the devices function, the available network, the nature and periodicity of the data, the requirements of the application, and the growth of the devices, among others. Both protocols can be efficient when applied properly for the intended IoT use.
When Should You Use MQTT for IoT App Development?
MQTT is an excellent protocol for IoT app development if there is a need for frequent and reliable transmission of small packets of information. MQTT will help in reducing bandwidth usage and enables real-time information sharing.
MQTT is a strong choice for:
- Smart home applications
- Industrial IoT
- Fleet monitoring
- Remote equipment monitoring
- Sensor networks
- Smart agriculture
- Real-time monitoring
- Connected devices
MQTT is suitable in resource-constrained environments where devices do not have sufficient resources or where network connectivity is not reliable. Moreover, MQTT’s publish-subscribe architecture makes it easy to gather data from various connected devices.
Companies that have IoT app development services will find it useful to implement MQTT for connecting devices, sensors, brokers, and applications effectively. MQTT may be integrated with APIs and cloud computing through IoT application development services where applications require real-time communication and more.
When Should You Use HTTP for IoT Applications?
HTTP can be a practical choice when IoT applications need to communicate with APIs, web services, or existing backend systems. It is commonly used for:
- IoT REST APIs
- Mobile applications
- Web dashboards
- Backend integrations
- Third-party systems
- Device configuration
- Data retrieval
HTTP works well when request-response communication is enough and applications need to exchange data with a server. It also supports integration with existing web infrastructure.
HTTP does not need to be avoided in IoT. The use of both MQTT and HTTP in a modern IoT application is possible.
For example:
MQTT: Device → Cloud for real-time telemetry
HTTP: Mobile App → Backend API for data retrieval or device management
MQTT and HTTP in a Modern IoT Architecture
A modern IoT architecture can use MQTT and HTTP together, with each protocol handling a different communication need.
IoT Sensors
↓
MQTT Broker
↓
IoT Backend
↓
Database
↓
API
↓
Mobile/Web Application
MQTT supports real-time telemetry data transfer from sensors to backend systems, whereas HTTP integrates applications with backend systems via REST APIs.
Mobile App ↔ REST API ↔ Backend
With the use of both these protocols, the IoT can select the best way for communication. The protocol of MQTT works well with device communication, while HTTP is a suitable choice for application-based requests, data fetching, configuration, and third-party integration.
This combined approach can support flexible and scalable IoT application architectures.
Security Considerations for MQTT and HTTP
Security is one of the important factors that should be taken care of while creating the connection between the Internet of Things system. Some of the security practices used in MQTT include TLS Encryption, authentication, authorization, access control, and secure broker configuration.
In HTTP, HTTPS using TLS secures the data transmission process, while authentication, authorization, APIs, and token-based authentication help secure access to backend systems.
Security should be developed for the entire IoT ecosystem and not just the communication protocols. Security for devices, brokers, API’s, clouds, applications, credentials, and storage is necessary. In addition, security planning includes updating, monitoring, and reviewing accesses to mitigate any risk that comes with growth in the IoT ecosystem.
How to Choose the Right Protocol for Your IoT Project
| Requirement | Recommended Approach |
| Frequent sensor messages | MQTT |
| Low bandwidth | MQTT |
| Real-time telemetry | MQTT |
| REST API | HTTP |
| Web integration | HTTP |
| Mobile/backend API | HTTP |
| Mixed architecture | MQTT + HTTP |
An IoT app development company can select the protocol based on device and application needs. IoT app development services may combine both for flexible architectures.
Planning an IoT application? Talk to our IoT app development experts to choose the right communication architecture for your devices, data and business requirements.
Wrapping It Up
MQTT and HTTP are used for different reasons when developing an IoT application. MQTT is best for real-time communication, whereas HTTP is better suited for APIs. There are many IoT applications where both MQTT and HTTP could be used effectively.
FAQs
CEO, Techerudite
