What Is Azure Service Bus


You can use a messaging platform to send messages between different parts of your application or business. Azure Service Bus is the technology used to implement messaging and eventing in cloud-based applications. It is one of the services in the Azure cloud platform, which uses the Advanced Message Queuing Protocol (AMQP) for Microsoft. AMQP is supported by Windows Server Service Bus through .NET 4.5 and above.

Azure Service Bus is the technology used to implement messaging and eventing in cloud-based applications

Azure Service Bus is a cloud-based messaging platform. It's one of the services in the Azure cloud platform, and it allows you to build highly scalable distributed systems that can send messages between applications or devices. For example, let's say you want to add an IoT device to your application so it can perform automated tasks based on sensor input. You could use Azure Service Bus to send those messages from your app to the IoT device. Azure Service Bus uses Advanced Message Queuing Protocol (AMQP) for its communication protocol, which was created specifically for interoperability between systems running on different platforms and environments.

Azure Service Bus is one of the services in the Azure cloud platform

Azure Service Bus is a service of Azure that provides reliable and scalable messaging for applications. It uses the Advanced Message Queuing Protocol (AMQP) to communicate between cloud applications, as well as on-premises resources. Using the service bus, you can send and receive messages from other systems. You can use it to create a custom protocol, or you can use one of the existing protocols that are supported in this service: AMQP 1.0/1.1 (Advanced Message Queuing Protocol), MQTT 3.1 (MQ Telemetry Transport), OpenWire 2, 0MQ 2, STOMP 1.2, or HTTP 1..1

Azure Service Bus uses the Advanced Message Queuing Protocol (AMQP)

AMQP is a standard protocol for messaging. It's used by many different systems, including Microsoft's own Azure Service Bus, and it's supported by many different languages. AMQP has been around since 2004, but even though its popularity has grown over the years and it seems like a technology that should be widely known, it isn't universally understood by IT professionals. This article aims to explain what AMQP is and why you might need it in your applications.

Azure Service Bus provides a secure and reliable communication for disconnected systems

You can send messages to other applications, even if they are not running in the same datacenter. You can send messages to other applications, even if they are not running at the same time. You can send messages to other applications, even if they are not running on the same machine.

In addition to messaging, you can also implement publish-subscribe and request/reply patterns. Pub-sub is a pattern where messages are sent to multiple recipients. Request/reply is a pattern where you send a request and get a response. Both publish-subscribe and request/reply use the same underlying technology in Azure Service Bus, so they work together seamlessly!

Azure service bus has a partner offering called on-premise service bus that allows you to host your own messaging infrastructure

On-premise service bus (also known as Azure Service Bus on prem) is an offering that allows you to host your own messaging infrastructure. You can use it if you want to keep data private and control access, or if you need to send messages across the internet. Some common scenarios for using on-premise service bus are: Sending messages between different parts of your application or business Streamlining interaction with partners and customers You can use Azure Service Bus to send messages between different parts of your application or your business. You can use Azure Service Bus to send messages between different parts of your application or your business. You may want to send messages between different applications, different systems inside your organization, or even between user devices and back-end services.

Azure Bus Service - How it works! 

Messages are used to move data between various apps and services. A message is a data-filled container that has metadata on it. Any type of information can be used as the data, including structured data stored in popular formats like JSON, XML, Apache Avro, and plain text.

Typical message situations include,


Transfer company information, such as journals, inventory movements, or sales or purchase orders.

Decouple applications.

Applications and services should be more scalable and reliable. It is not necessary for both producers and consumers to be online or available at the same time. The load is leveled such that traffic surges don't overtax a service.

Load balancing.

Permit many concurrent consumers to safely claim exclusive ownership of individual messages while reading from a queue.

Topics and subscriptions.

Enabling 1: n relationships between publishers and subscribers will allow subscribers to select messages from a published message stream.

Transactions. enables you to perform many operations inside the context of a single atomic transaction. The following operations, for instance, can be carried out inside the parameters of a transaction.

  • Messages from one queue should be obtained.
  • Processing results should be posted to one or more queues.
  • The input message should be moved from the original queue.

Only upon success, including the successful settlement of the input message, do the results become apparent to downstream consumers, enabling once-only processing semantics. The compensatory transactions pattern in the larger solution context has a solid foundation in this transaction model.

Message sessions.

Implement high-level process coordination and multiplexed transfers that call for message deferral or stringent message ordering.

The ideas of the Service Bus are comparable to those of other message brokers, such as Apache ActiveMQ. One significant distinction is that because Service Bus is a platform-as-a-service (PaaS) solution, you don't have to worry about performing the following tasks. Azure handles those errands for you.

  1. Concerned about hardware malfunctions
  2. Keeping the products or operating systems patched
  3. Managing disc space and adding logs
  4. managing a backup
  5. Switching to a backup machine

Let's look at various components used on Azure Service Bus.


Queues are used for both sending and receiving messages. Messages are held in queues until the receiving application is ready to accept and handle them.

What is Azure Service Bus?

On arrival, messages in queues are sorted and timestamped. If the namespace is zone-enabled, the message is always held durably in triple-redundant storage after being accepted by the broker. Until a client reports a message as accepted, Service Bus retains it in memory or other volatile storage.

Pull mode message delivery only sends messages in response to requests. Contrary to some other cloud queues' busy-polling models, the pull operation can last a long time and is only finished when a message is ready.


Topics can be used to send and receive messages as well. For point-to-point communication, a queue is frequently utilized, however, topics are helpful in publish/subscribe applications.

What is Azure Service Bus?

Multiple, independent subscriptions are possible for topics. These subscriptions attach to the topic and otherwise function precisely like queues from the receiver side. Each message sent to a subject can be copied and sent to a subscriber of that topic. Named entities are subscriptions. Although subscriptions are designed to last indefinitely, they can be set to expire and then be deleted automatically. You can also build volatile subscriptions with Service Bus Premium using the Java Message Service (JMS) API, which is active only while the connection is active.

On a subscription, rules can be set. A filter to specify the prerequisites for a message to be copied into the subscription and an optional action to change message information are both included in a subscription rule. See Topic filters and actions for additional details. The following situations call for the use of this feature:

  1. A subscription shouldn't be set up to receive every message published on a topic.
  2. When messages go through a subscription, you want to mark them up with additional metadata.


All messaging components are contained in namespaces (queues and topics). A namespace can contain many queues and topics; thus, namespaces frequently act as containers for applications.

A namespace can be compared to a server in the terminology of other brokers, but the concepts aren't directly equivalent. A Service Bus namespace is your own capacity slice of a large cluster made up of dozens of all-active virtual machines. It may optionally span three Azure availability zones. So, you get all the availability and robustness benefits of running the message broker at an enormous scale. And you don't need to worry about underlying complexities. Service Bus is serverless messaging.

Advanced features

Additionally, Service Bus includes sophisticated features that let you handle trickier messaging issues. These major characteristics are explained in the sections below:

Message sessions

Use sessions to implement a first-in, first-out (FIFO) guarantee in Service Bus. The combined and organized handling of unlimited sequences of linked messages is made possible by message sessions.


You can chain a queue or subscription to another queue or topic that is a part of the same namespace using the auto-forwarding capability. When auto-forwarding is activated, Service Bus automatically moves messages from the first subscription (source) or queue (topic) to the second queue (topic) (destination).


Dead-letter queues (DLQs) are supported by Service Bus and are used to store messages that cannot be processed or delivered to any receiver. After that, you can examine and remove messages from the DLQ.

Scheduled delivery

For further processing, you can add messages to a queue or topic. To plan a job, for instance, so that it becomes accessible for processing by a system at a specific time.

Message deferral

When a queue or subscription client receives a message that it wants to process but it can't right now due to unique conditions in the application, the entity might postpone retrieving the message until a later time. The message is placed aside but is still in the queue or subscription.


A transaction creates an execution scope by combining two or more operations. Within the context of a transaction, Service Bus supports grouping operations against a single messaging entity (queue, topic, or subscription).

Filtering and actions

Subscribers can specify which messages from a subject they want to receive. In the form of one or more named subscription rules, these messages are described. The subscription generates a copy of the message under each matching rule condition, which may be annotated differently for each matching rule.

Auto-delete on idle

You can define an idle interval with auto-delete on idle, after which the queue will be automatically erased. When there is an activity in the queue, the interval is reset. Five minutes is the bare minimum.

Duplicate detection

Multiple detections eliminate uncertainty in these cases by allowing the sender to transmit the same message again, and the queue or topic discards any duplicate copies if an error occurs that leaves the client uncertain about the outcome of a send operation.

Shared access signature (SAS), Role-based access control, and managed identities

For Azure resources, Service Bus provides security protocols like Managed identities, Role Based Access Control, and Shared Access Signatures (SAS).

Geo-disaster recovery

Geo-disaster recovery enables data processing to carry on in another Azure region or data center when those regions or data centers go down.


Standard HTTP/REST and Advanced Message Queuing Protocol (AMQP) 1.0 protocols are supported by Service Bus.

Compliance with standards and protocols

Advanced Messaging Queueing Protocol (AMQP) 1.0, an open ISO/IEC standard, is the main wire protocol for Service Bus. Customers can use it to create programmed that interact with Service Bus and locally installed brokers like ActiveMQ or RabbitMQ. If you desire to construct such an abstraction, the AMQP protocol guide offers comprehensive guidance.

The Java Message Service (JMS) 2.0 API for Java/Jakarta EE is completely compliant with Service Bus Premium. Also supported by Service Bus Standard is the queue-focused subset of JMS 1.1. JMS is a typical message broker abstraction that works with a wide range of programs and frameworks, including the well-known Spring framework. You simply need to reconfigure the queue and topic structure, update the client provider dependencies, and configure Azure Service Bus to replace other brokers. See the ActiveMQ migration guide for an illustration.

Client libraries

The Azure SDK offers fully supported Service Bus client libraries.

  1. .NET Azure Service Bus
  2. Libraries for Azure Service Bus in Java
  3. Java JMS 2.0 provider for Azure Service Bus
  4. Modules for JavaScript and TypeScript in Azure Service Bus
  5. Microsoft Azure Service Bus libraries

Any AMQP 1.0 compatible protocol client can use Azure Service Bus’s main protocol, AMQP 1.0. There are samples available for several open-source AMQP clients that specifically show Service Bus compatibility. To learn how to directly use Service Bus capabilities with AMQP 1.0 clients, consult the AMQP 1.0 protocol guide.


Service Bus seamlessly connects with a variety of Azure and Microsoft services, including:

  1. Event Grid
  2. Logic Apps
  3. Azure Functions
  4. Power Platform
  5. Dynamics 365
  6. Azure Stream Analytics

Features of Azure Bus Service

Simplify business messaging on the cloud

Count on Service Bus if you require extremely dependable cloud messaging between apps and services, even when those services aren't running. This completely managed solution, which is accessible in all Azure regions, removes the responsibilities of server management and licensing. Asynchronous operations, structured first-in, first-out (FIFO) messaging, and publish/subscribe capabilities provide you more freedom when brokering messaging between client and server.

Construction of scalable cloud solutions

Use the strength of asynchronous messaging patterns to scalable your enterprise systems with dependability. Integrate Service Bus communications with cloud resources like Azure SQL Database, Azure Storage, and Web Apps to get stable operation under variable loads and the resilience to withstand intermittent failures.

Implement complex messaging workflows

Build messaging structures with complicated routing to increase availability. Utilize Service Bus to fan out message delivery at scale to downstream systems and deliver messages to a variety of subscribers.

Enable your existing Java Message Service (JMS 2.0) applications to talk to Service Bus over AMQP

Without worrying about license prices or operating expenses associated with running your messaging broker in an on-premises or infrastructure as a service (IaaS) environment, get a fully managed corporate messaging solution with native JMS support.

Service Bus pricing

Connect across private and public cloud environments

A messaging architecture called Azure Service Bus stands in between applications, enabling message exchange for increased scalability and resilience.

For more details, please check the link below.



Message queues and publish-subscribe topics are features of the fully managed enterprise message broker Azure Service Bus (in a namespace). The following advantages are available when using Service Bus to decouple applications and services from one another:

  • Distributing tasks among rival employees.
  • Exchanging data and control across service and application boundaries in a secure manner.
  • Coordinating transactional work that requires a high degree of reliability.

Messages are used to move data between various apps and services. A message is a data-filled container that has metadata on it. Any type of information can be used as the data, including structured data stored in popular formats like JSON, XML, Apache Avro, and plain text.