Patterns: Serial Process Flows for Intra- and Inter-enterprise

70 Patterns: Serial Process Flows for Intra- and Inter-enterprise

Application pattern next. If the Extended Enterprise Business pattern is not

appropriate for your development efforts, review the Business patterns to

determine which pattern best addresses your e-business needs.

4.3 Application patterns

We present the Extended Enterprise Application patterns in order of increasing

flexibility and sophistication. As the Application patterns build on each other, their

capabilities and reliance on middleware increase, and they require less

application development effort. Select the following Application pattern that best

fits your requirements:

 Exposed Direct Connection Application pattern: Message/Call

Connection variations

 Exposed Broker Application pattern: Router variation

 Exposed Serial Process Application pattern: Also known as Managed

Public Processes

The diagram conventions shown in Figure 4-2 are used to describe these

successful approaches in the following Application patterns.

Figure 4-2 Application pattern diagram conventions

Note: The Exposed Parallel Process Application pattern is another possibility,

but it is not currently being observed in the Extended Enterprise domain. It is

expected to appear at some later stage.

Transient data

Work in progress

Cached committed

data

Staged data

(data replication flow)

Application node containing

existing code with no need

for modification for this project

or that cannot be changed.

Read/write data

Read only data

Application node

containing new or modified

code for this project.

A set of applications whose

characteristics are unspecified.

Only the means with which

to interact with them is specified.

A small solid circle indicates the initiating node.

A single arrow indicates that a response is not needed.

Double arrows indicate that a response is needed.

Chapter 4. Extended Enterprise pattern 71

Business and IT drivers

Table 4-3 and Table 4-4 summarize the business and IT drivers for the Extended

Enterprise Application patterns and their variations.

Table 4-3 Business drivers

Business drivers

Exposed Direct Connection

Message variation

Exposed Direct Connection

Call variation

Exposed Broker Router

variation

Exposed Broker

Exposed Serial Process

Exposed Serial Workflow

variation

Improve organizational efficiency üüüüüü

Reduce the latency of business events üüüüüü

Support a structured exchange with business partners üüüüüü

Support real-time one-way “message” flows to partner

processes

üüüüü

Support real-time request/reply “message” flows to partner

processes

üüüüü

Support dynamic routing of “message” between partners to

one of many target applications

üüüü

Support dynamic distribution of “message” between partners

to multiple target applications

üüü

Support automated coordination of business process flow

between partners

üü

Support human interaction and intervention within the

process flow between partners

ü

72 Patterns: Serial Process Flows for Intra- and Inter-enterprise

Table 4-4 IT drivers

QoS concerns

The following QoS concerns are of particular importance when working in the

Extended Enterprise domain.

Availability

High availability can be a particularly significant issue in the inter-enterprise

integration domain. It is important that you use careful availability management to

provide acceptable levels of customer service or, in some cases, to meet

contractual obligations regarding the availability of the application service being

provided.

IT drivers

Exposed Direct Connection

Message variation

Exposed Direct Connection

Call variation

Exposed Broker

Router variation

Exposed Broker

Exposed Serial Process

Exposed Serial Workflow

variation

Minimize total cost of ownership (TCO) üüüü

Leverage existing skills üüüüüü

Leverage the legacy investment üüüüüü

Enable back-end application integration üüüüüü

Minimize application complexity üüüüüü

Minimize enterprise complexity üüüü

Improve maintainability üüüü

Improve flexibility by externalizing process logic from

application logic

üü

Support long running transactions ü

Important: This profile is intended as a rough preliminary guide to QoS

concerns that differentiate this domain, suitable for high-level architectural

design. This is not a substitute for thorough analysis at a later design stage.