These characteristics, which we cover in depth in
Section 3.1
, include how those relationships are influenced by the following factors detailed in the same section:
-
Platform
-
Location
-
Protocols
-
Programming language
-
Invocation patterns
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Security
-
Service versioning
-
Service model
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Information model
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Data format
Enterprise services share some or all of these characteristics that impact what actions the service performs, how it does so, and whom it interacts with. These services can be reclassified in the SOA model and placed into new domains that describe what function they perform in the overall model. An analysis of the preceding list identifies at least four different domains of architecture, along with subdomains that influence where a service can exist and the function it performs. These domains and subdomains, discussed later in this chapter, are as follows:
It is essential to maintain a separation of concerns and domains. In an enterprise, these domains can have separate implementations using any permutation of packaged applications, custom applications, existing infrastructure, and external or outsourced services.