In the early days of web application development, monolithic frontends and backends were perfectly fine. But the emergence of the cloud has changed expectations. Developers want to build applications that exchange information with APIs (Application Programming Interfaces). Business owners want faster development times. End users expect zero downtime. This new paradigm enabled the rise of service-oriented architecture (SOA) and, along with it, microservices and web services.
At first glance, microservices and web services seem very similar, and it may be hard to tell the difference between them. They both fall under the category of API representation tools. That is, they are both ways to deliver and share information via APIs. It's common to find applications that use both microservices and web services, but they serve different needs. The first thing to understand is that microservices and web services deal with different concepts in modern application design.
In practice, however, both microservices and web services are important concepts in services-oriented application architectures. Understanding how both fit into the bigger picture of modern app design is essential.
Here are the key differences between microservices and web services:
Some basic definitions of microservices and web services are:
Looking at those definitions, the functions of microservices and web services can look the same. That's because web services can be seen as microservices in and of themselves. But they're microservices that strictly function on the web and other internet services.
However, microservices and web services are not synonymous, and the biggest difference is in how they build application architectures. Here's a look at their respective architectural styles:
It’s common for modern, services-oriented application architectures to include a mix of microservices and monolithic applications. It’s also common for them to use a combination of APIs and web services to integrate the apps and microservices services that comprise them.
The microservices application architecture breaks a traditional monolithic application into its component functions.
Rather than programming all application functions into a single piece of source code – as a monolith does – the microservices architecture isolates each function as small, autonomously-running applications. These small and independent applications are microservices, which typically run in a containerized environment.
This design philosophy is what is known as componentization. The major advantage of componentization is that all services of an application be deployed independently. In traditional monolithic development, all of an application's functions and services rely on a single large code base. Changes to the code can affect all parts of the application. But when services are developed as components, they are independent of each other and can be upgraded or replaced as needed without affecting the application as a whole.
A group of microservices that make up a microservices-based application usually interconnect with each other through APIs. When developing a microservices-based application like this, developers can use an API gateway – like DreamFactory – which offers an easy way to manage access to, and establish integrations with, the application's microservices.
APIs are the preferred method for connecting microservices because APIs support the widest variety of message formats (such as XML, XML-RPC, JSON, etc.) and the widest variety of message protocols (such as HTTP, HTTPS, MQTT, REST, and SOAP).
This flexibility in formats and protocols makes microservices and the microservices application architecture popular among developers.
As we’ll discuss in the next section, developers can also connect microservices apps via web services to form a web services application architecture.
Before we get into that, if you'd like a more detailed overview of how microservices work, please read our guide “What Are Microservices?”
Microservices offer several benefits that can positively impact your software development and deployment. With microservices, you can scale individual services independently, allocate resources efficiently, and handle varying workload demands effectively. Microservices also enable faster development cycles, allowing teams to work on different services concurrently and introduce new features and updates quickly. The loose coupling of microservices promotes improved fault tolerance and system resilience. Additionally, microservices allow for the adoption of different technologies for each service, promoting flexibility and the use of suitable tools for specific functionalities. The small, independent nature of microservices enhances modularity, making it easier to understand, update, and maintain individual services without affecting the entire system.
Instead of carrying out a specific function on behalf of a larger application, web services provide a standardized, web-based interface that makes the services available to other applications on the internet.
W3.org sums up the role of web services like this:
A web service is a software system designed to support interoperable machine-to-machine interaction over a network. It has an interface described in a machine-processable format (specifically WSDL). Other systems interact with the web service in a manner prescribed by its description using SOAP messages, typically conveyed using HTTP with an XML serialization in conjunction with other web-related standards.
Since web services allow various apps to connect and interact with each other, they are more like the glue that developers use to connect individual apps and build a web services application architecture. Web services are often equated with APIs as if the two are one and the same. A better way to look at it is that web services are one of the many representations of APIs. Artjoker Blog explains this distinction:
(A web service) is only one of the many API representations that use HTTP protocol for connection with third-party software solutions (for fairness’ sake, we’ll note that in rare cases, this connection is established via the other transport protocols like SMTP).
Another way of understanding web services is to view them as an “HTTP wrapper” around an API. This wrapper lets applications present their services through a web interface so other applications or microservices can interact with those services. Web services are popular because they allow this exchange of services and data, even when the connecting systems are written in different programming languages or running on different platforms.
In this way, a web service functions as a bridge–regardless of whether the connection is cloud-to-cloud, server-to-server, server-to-premises, cloud-to-premises, or client-to-server. This makes web services particularly valuable for enterprises that want to connect diverse software components running in different locations.
However, there are some conditions you’ll need to keep in mind when using web services:
Fortunately, an advanced iPaaS solution like DreamFactory can quickly overcome this lack of connection flexibility by converting messages from one format/protocol to another.
With that in mind, let's take a look at how web services work.
Here’s a quick overview of how a SOAP-based web service works to establish integrations between the application it offers services for and a third-party client:
Web services offer several benefits that positively impact system integration and interoperability. They enable seamless communication and integration between different platforms and technologies, ensuring interoperability regardless of the underlying systems. Web services follow standardized protocols, making them simple to implement and integrate into existing systems. This simplicity of implementation reduces development time and costs. Web services also enjoy broad industry support, compatible with various programming languages and frameworks, ensuring wide adoption and accessibility. Additionally, web services facilitate cross-platform communication, allowing different applications and systems to exchange data and services regardless of their operating systems or hardware platforms. Overall, web services provide organizations with interoperability, simplicity of implementation, cost-effectiveness, and broad industry support.
Let’s look at the similarities and differences between microservices and web services from several different angles:
A microservice carries out a highly specific service or task. This is known as "service specificity."
The Facebook Messenger platform includes a microservice that handles file attachments. You can access this particular functionality by using Facebook’s Attachment Upload API. As the microservice exists specifically to handle the process of uploading and attaching files, this is an example of a microservice with service specificity that many of us are familiar with.
In contrast, a web service can offer one or many services from a single application. This allows a web services architecture to organize access to the different services provided by an application.
For an e-commerce application, one web service could present customer-facing ordering and payment services, while another web service presents non-customer-facing inventory services. Even though separate web services offer access to these services, they belong to the same application.
This is an example of how web services can help you manage and control access to the various services that belong to the same application and are not bound by service specificity.
With architectures built on both microservices and web services, developers can easily add, remove, and upgrade the microservices and applications that form a larger application architecture. This modularity results in a more flexible, agile architecture because upgrades are faster, cheaper, and easier to achieve without disrupting the entire application.
With microservices, the APIs that connect them offer greater flexibility because they support both HTTP and HTTPS, and they can establish connections between dissimilar message formats and protocols.
Conversely, web services do not support HTTPS, and the connected components must share the same message format and protocol. That being said, an iPaaS like DreamFactory can easily overcome the message format and protocol requirements to ensure a successful exchange over web service connections.
Microservices often run in containers. Since multiple containers can run on the same operating system kernel, this reduces costs by requiring fewer operating system licenses to run the various microservices that comprise a larger app architecture.
Also, the universal connective capacity of APIs means that developers save time and money when establishing microservices API connections. This is because they can forego the labor required to build a hand-coded, point-to-point connection.
Since web services are an HTTP-based presentation of APIs, they also forego the time and expenses of hand-coded, point-to-point integrations.
Finally, the pluggable nature of both microservices and web services architectures makes upgrades faster, simpler, and more cost-effective.
In microservices and web services architectures, the failure of one microservice or application is less likely to result in a cascade failure that affects the rest of the ecosystem. With both architectures, developers can implement a circuit breaker design pattern to detect service failures and prevent them from disrupting other microservices or applications connected to the system.
Developers can create both microservices or web services architecture by connecting applications running on any platform written in virtually any programming language. This allows developers to choose the most suitable languages and platforms for the different microservices, apps, and web apps that comprise an architecture. It’s also easy for them to establish premises-to-premises, premises-to-cloud, and cloud-to-cloud integrations.
Microservices and web apps allow for smaller, more focused, and easier-to-manage development teams. Managers can assign ownership of each web service or microservice to a small development team. This allows teams to work independently and with granularity, perfecting a single aspect of the application without the fear of coding conflicts with other systems.
However, it should be noted that web services development teams must stay on the same page concerning the common messaging formats and protocols shared across web service integrations.
Here are the key differences between Microservices vs Web Services:
When considering the architectural design for your applications, it's important to evaluate whether microservices or web services align better with your specific needs. Both approaches have their advantages and considerations, so understanding the factors that impact your decision is crucial.
Microservices are an architectural style where applications are built as a collection of small, independent services that can be developed, deployed, and scaled independently. They promote loose coupling, flexibility, and agility, making them well-suited for complex and rapidly evolving systems. Microservices enable teams to work on different services concurrently, fostering faster development cycles. However, they require additional effort in terms of service discovery, inter-service communication, and managing a distributed system. Microservices may be a good fit if you prioritize scalability, flexibility, and have the resources to manage a distributed architecture effectively.
While it’s true that microservices and API connections are getting the most attention these days, there are some situations when web services are better for connecting applications:
In general, web services work well for complex projects that communicate information over a network. They are also a good choice for bigger enterprise application environments because they can integrate between many other applications and platforms that might otherwise not have interoperability. Of course, business and project requirements should always be the determining factor when choosing the ideal architecture for any software project.
The choice between microservices and web services depends on several factors, including budget, implementation complexity, and specific requirements. Consider the scalability and agility needs of your application, the availability of resources for managing a distributed architecture, and the level of interoperability required.
After reading this guide, you should have a better idea of what microservices and web services are — and how microservices and web services-based applications are different. You should also be able to recognize the situations when web service connections offer a better solution than APIs.
If you’re in the process of developing a new application or IT infrastructure, the DreamFactory iPaaS can blow through your integration bottlenecks. As an advanced API gateway and web services connection solution, DreamFactory can automatically convert XML to JSON and SOAP to REST for web services integrations. Moreover, the platform features a point-and-click interface to instantly generate REST API for any system you want to connect.
The main difference lies in their architectural design and scope. Microservices are an architectural style where applications are built as a collection of small, independent services, while web services refer to standardized approaches for interoperable communication between systems.
Microservices offer fine-grained scalability, allowing individual services to be scaled independently based on demand. In contrast, web services are typically designed to handle larger loads, often requiring the scaling of the entire system rather than specific components.
Microservices provide high flexibility and agility, as each service can be developed, deployed, and scaled independently. Web services, on the other hand, offer simplicity and ease of implementation but may have less flexibility for rapid changes or evolving system requirements.
Microservices enable teams to work on different services concurrently, facilitating faster development cycles and the ability to introduce new features more quickly. Web services often involve a more monolithic development and deployment approach, where changes may require coordination across the entire system.
Web services are specifically designed for system integration and interoperability, providing standardized protocols and communication mechanisms for seamless interaction between different platforms and technologies. Microservices prioritize internal service-to-service communication within a more cohesive architecture.
Microservices introduce additional complexity due to their distributed nature, requiring mechanisms for service discovery, inter-service communication, and fault tolerance. Web services are generally simpler to implement and manage, relying on well-defined protocols and standardized communication mechanisms.
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