This content is part of the Essential Guide: API integration tutorial: Latest trends and strategies

Exploring IBM API Management, middleware for app integration

IBM API Management, in the cloud or on premises, is application integration middleware that allows developers to subscribe to, publish, design, control and secure APIs.

IBM API Management, often referred to as APIM or IBM APIM, is application integration middleware that enables organizations to publish business services to internal and external application developers across on-premises and public and private cloud environments. The latest iteration of the on-premises version is 4.0.2. The cloud version is software as a service, often referred to as APIM SaaS. This product manages and enforces the consumption of APIs and includes usage analytics, lifecycle management, developer portal and API gateway integration for runtime enforcement.

IBM API Management focuses on the point of integration when businesses provide data to other application developers via a published and documented service outside their enterprise's organizational boundary. The service owners or API providers get full control of who can subscribe to their service, which user's organization is using which service, how much it's being used, version control and lifecycle management. To ensure proper security policies are applied and only the entitled levels of access are occurring, subscriptions are enforced at runtime.

APIM allows API management from different roles. Application developers can browse an integrated API portal, understand APIs, interactively try out APIs, register their application, subscribe to visible APIs, choose available API plans, request security keys, invoke APIs, analyze their application or API usage, participate in a built-in discussion forum, and comment on and rate APIs. On the IT operations side of the business, a user can manage the on-premises API environment infrastructure and monitor and scale it without disruption to the published service.

Specifically, API developers can design, secure and control RESTful and SOAP APIs on premises or in the cloud, stage APIs to an integrated API Gateway, publish APIs to select developer communities using varying rate limit plans, and analyze API usage and performance.

The middleware system lets organizations put their services under management control before sharing them with internal or external developers. It is most often used when providing an omnichannel view of business data and also when providing controlled and managed access to enterprise services and partners.

The on-premises deployment architecture consists of two components: management and the IBM DataPower Gateway. These are independently scalable and can be purchased separately. The API management component is a prerequisite for the gateway component.

APIM SaaS is an integrated hosted and managed service that does not reveal any separate components to the user. There is a portal for developers (API subscribers) to explore API documentation, request access to APIs, request application keys, and receive a self-service social and interactive experience. There is also an API administration portal for API developers (API providers) to define and manage APIs, create entitlement plans with varying rate limits, analyze API usage and manage API user communities.

The IBM API Management offering can discover services and APIs from IBM z/OS mainframe systems running CICS or IMS. As a result, existing RESTful or SOAP services on z/OS can be shared with application developers via a developer portal with full management and security control enforced. Additionally, APIM can discover services from IBM WebSphere Registry & Repository.

APIM is integrated with the IBM Integration Bus (IIB) message broker. This allows an integration developer using IIB Toolkit to push an API definition directly into APIM for management and security control before sharing with developers. APIM is also integrated with IBM Cast Iron so cloud integration developers using Cast Iron Studio can push API definitions directly into APIM for management and security control before sharing with developers.

IBM API Management is available both as a cloud service and also on premises. It is available either as a multi-tenant cloud service or as a service in Bluemix, IBM's cloud development platform, or as a dedicated single-tenant service. All installation and infrastructure monitoring is performed by IBM.

For on-premises deployments, the management and gateway components are packaged as virtual appliances that require either VMWare ESXi or vCenter, or Citrix XenServer or IBM PureApplication System.

Organizations of all sizes across all industries and geographies use IBM API Management.

A new feature in version 4 provides full support for Swagger 2.0 REST API description language, an integrated content management system-based portal for developers, lifecycle management for design-time for APIs and Plans, REST APIs to extend the solution, Bluemix integration, IIB integration and Cast Iron integration.

Variations of the APIM are available on premises and in the cloud, as well as in Bluemix, Bluemix Dedicated and Bluemix Local.

On-premises APIM is licensed using IBM's standard Processor Value Unit model.

APIM SaaS and Bluemix are licensed using a usage-based model: the number of API calls per month, number of API subscribers and amount of disk storage for detailed analytics data.

IBM API Management on Bluemix Dedicated and Local are licensed using a workload capacity model: the number of API calls per second.

A free, 30-day trial is available. It is a full-featured version and is the same as the paid cloud service offering. For on-premises deployment, the product is available for a 60-day evaluation. It is a full-feature version and is the same as the paid on-premises service offering.

Standard and premium support contracts are both available. Standard support costs are a percentage of the products' purchased price. Premium support is offered at a fixed price/term optional offering.

Next Steps

Middleware is just one of the few types of application integration products. Figure out which type is right for your company.

There's a big difference between traditional and mobile application integration.

Integrating with a service bus makes it easier for disparate systems to talk to each other and share data.

Dig Deeper on API management