Enterprise Architecture in cloud service era using mixed software as service

By reading this article, it architects will learn how to use the EA tag and IBM Rational System Architect to communicate effectively with business users and other stakeholders, including service providers.

Good Enterprise Architecture (EA) is the main driver of effective adoption of a service-oriented architecture (SOA), which was proposed a few years ago, and many customers have paid for project failure or half failure due to lack of "due diligence" on EA. The main components of the architecture (End-to-end connectivity between business processes and IT services) and the ongoing governance mechanisms provided by the established enterprise architecture are essential elements for an SOA to maintain its technical commitment to transforming the business and the enterprise.

Now, I can hear your head buzzing, and you may be thinking, "I must have opened the wrong article." This was supposed to be about cloud computing, not an article about SOA. ”

The fact is, whether we're talking about cloud or SOA, we have to deal with services.

"Service" means that we are willing to admit that the granularity of architectural IT may not be optimal for a particular problem at hand, and we are willing to accept some of the Over-engineer (the part of the excessive design) to support more flexible, rescheduled business operations. (Take the standardized interface for example.) It is not free and will only be rewarded if you really reuse its functionality. This level of flexibility is itself a means of achieving flexible business processes. Again, these processes provide meaningful economic rewards only when they support flexible, sensible business strategies.

When implementing a cloud (or SOA) architecture, this causal chain must be placed in front of the architect. Otherwise, their decisions will always lack the consideration of some key aspects of the problem.

This means that transforming the Enterprise architecture model in this domain is the execution of due diligence to identify the relationship, dependencies, requirements, and constraints of the business to it.

In this article, we will explore how to represent this model from the perspective of the consumer of cloud services, and how to understand what needs to be done and why. The consumer could be an organization that wants to use cloud technology to inject higher levels of flexibility into its operations.

Cloud Services Consumer Scenario

Cloud reference architectures, such as the cloud Reference Architecture provided by the National Institute of Standards and Technology (NIST) at IBM or the United States Department of Commerce, start the architecture cloud business from the set of roles involved. Each operator has a clear role.

Figure 1. IBM Cloud Reference Architecture, similar to the NIST Cloud Reference Architecture

The IBM Reference Architecture identifies the following roles:

Cloud Service Creator (Cloud service creator), develop new services that will be used through the cloud infrastructure Cloud service Provider (cloud service provider), manage and operate cloud infrastructure Cloud Service Consumer (Cloud service consumer), using services hosted in the cloud infrastructure

NIST lists the following roles:

Cloud Provider (cloud provider, IBM-like cloud service provider) Cloud Consumer (cloud Consumer, same) Cloud auditor (Cloud Auditor), can independently evaluate cloud services Cloud broker (Cloud Broker), Be able to mediate, compose Provider service, and make its value-added Cloud Carrier (cloud operator), capable of providing transport services connected to Cloud service Provider

As you can see, Provider (supplier) and Consumer (consumer) are core roles. Although the vendor's business and IT models are very similar to the traditional outsourcing model, consumers are the ones who make the most of the cloud innovation capabilities.

Back to IBM Cloud Reference architecture, consumers can choose from four types of services:

infrastructure Services (known as "infrastructure as a service", or IaaS), consumers use service platform services (PaaS, platform, or service) equivalent to a hardware system where services are equivalent to a complete hardware and software infrastructure software service (SaaS, software as a service), Consumers use business application business processes as services (sometimes referred to as BPaaS), and consumers outsource part of their business processes to external suppliers

The provider and the consumer may be two departments in the same company (for example, IT operations and IT development) who use a private cloud; they may also be two separate business entities, one of which is responsible for delivering services through the cloud. The latter is the most interesting example, because it involves changes to the business model of the enterprise, not just the model changes of one of its organizational entities.

Of these four types of services, this article focuses on specific scenarios that use business applications provided through cloud services (public SaaS) to gain new business functionality.

The last point involved in the ability of the cloud model is "platform." The goal, of course, is to provide services, but the quality of the services provided depends on the technical and business support capabilities provided by the platform (two pink squares in IBM Reference architecture).

IBM Cloud Reference Architecture recognizes the following support services:

Service product catalog and Management Service request management order and subscription management contracts and agreements management pricing, metering and billing customer account management level settlement and payment, accounts payable, Accounts Receivable service delivery directory service Automation management change and configuration management Image Lifecycle management configuration events and issues management IT service level management Monitoring and event Management IT Asset and license management capacity and performance management platform and virtualization management

Some of these services explicitly support the business and technical processes of the provider, some of which require consumer involvement, and for them, some services may actually be new services, such as payment bills for services, links to external monitoring information (to control the quality of the services purchased), and so on.

Note：
Even though we recommend that their (EA) analysis be part of a technical due diligence process that uses any cloud-based service, this article is limited in length and does not focus on them.