Building SOA portfolio Business Services, part 7th: Multi-rent support for composite business services

Introduction

The previous article in this series describes the concept of a composite business service (CBS) and discusses some of the core elements of the deployment environment it needs. This article describes multiple-rent (that is, the ability to provide services to multiple organizations (customers) from a shared public hosting environment). It will also introduce a network delivery method for the software as a service (SOFTWARE-AS-A-SERVICE,SAAS) and different user types that may take advantage of SaaS multiple-sublet. We will describe the principles and technology implementations that support multiple sublet in a SaaS hosting environment. This article provides a multi-tenant platform implementation that uses the cloning and configuration implementation pattern of websphere®process Server and WebSphere portal, virtual portals, and portlets. With the example, we can also learn how to make changes to the Portlet implementation to support extended profile information for portal roles. This article will focus on the design changes to the software services and the Portlet-based user interface to support subscribers and end users.

Multi-Rent

In Software as a service (SaaS) model (also known as on-demand software), the delivery of services (such as services described using WSDL) is based on network-based access to the service provider's software products. This approach contrasts with the delivery of traditional compressed packaged software through installation mechanisms. A typical service provider hosts its software in a large data center and delivers business services using the Internet. Although the example in this article focuses on specific cases where a service provider is a stand-alone enterprise, a service provider can also be a department in a large enterprise.

Figure 1 depicts a SaaS example. Where the bank account Opening service provider hosts the implementation of the Account Opening service, and each Subscriber (tenant) of the service is a bank, such as the one and Second Canadian bank. Each bank will, in turn, deliver the bank-specific account Opening service configuration to its customers.

Figure 1. SaaS Example

Building SOA portfolio Business Services, part 1th: Developing a SOA composite application to support business services by giving detailed examples of roles in a banking SaaS application. The ability of part 1th to support multiple Business service subscribers (lessees) from a service provider's public shared hosting environment is called a multiple-sublet.

Multi-sublet support is a design idea that is considered in the whole run-time stack. It requires careful consideration of all levels of the runtime Environment topology, service implementation, and user interface. The Multiple Tenant platform implementation options cover a wide range of aspects: from hardware-based to virtualization technology. In extreme cases, each Subscriber may be hosted by a set of dedicated hardware and software. This topology provides subscribers with the greatest flexibility by selecting the various options available in the actual hardware used in the hosting environment. For example, you can select a specific performance by selecting the CPU. You can also select a reliability level based on server hardware. However, this topology may be the most expensive because it forces the provider to manage a series of dedicated servers for subscribers. Providers can achieve cost savings by sharing hardware for many customers. For example, a provider can reduce costs by installing multiple databases on a database (one database per customer). The provider can also share instances of the application server to host multiple instances of the business service.

Conceptually, the range of options for a multi-tenant platform can be roughly categorized as one of the following categories:

Not shared at all

Sharing physical Servers

Sharing applications

It is important to recognize that even in a completely unshared environment, you can benefit from well-defined topologies, public hardware/software product definitions, and roadmap maps for reference. The shared server classes are fairly extensive, including the following options:

Share only support infrastructure (provided by products such as tivoli®provisioning Manager)

Share security features implemented using products such as Tivoli access Manager and WebSeal

Share database services that use products such as DB2

Shared middleware, such as applications, processes, and portal servers

This article discusses the last shared application: In this environment, the entire stack (including hardware and software) is reused throughout the user base; You can configure the software for individual subscribers (while preserving custom options).

In the context of this article, we will learn how to achieve multiple-sublet support. Next, we will focus on the three core service types needed to assemble the application, as shown in Figure 2.

Figure 2. Composite Application Services