Enterprise Architecture in the cloud service era: using mixed software as a service (SaaS)

Brief introduction

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 you buzzing in your head, 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) to develop new services that will be used through the cloud infrastructure

Cloud Service Provider (cloud service provider), managing and operating the 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), which enables independent evaluation of cloud services

Cloud broker (Cloud Broker), can act as intermediary, make up Provider service and add value to it

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 using services equivalent to the hardware system

Platform Services (PaaS, Platform-service) where services are equivalent to a complete hardware and software infrastructure

Software services (SaaS, software as a service), consumers use business applications

Business processes are 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).