Select a Pattern Agnostic Capability Agnostic Context Agnostic Sub-Controller Asynchronous Queuing Atomic Service Transaction Brokered Authentication Canonical Expression Canonical Protocol Canonical Resources Canonical Schema Canonical Schema Bus Canonical Versioning Capability Composition Capability Recomposition Compatible Change Compensating Service Transaction Composition Autonomy Concurrent Contracts Contract Centralization Contract Denormalization Cross-Domain Utility Layer Data Confidentiality Data Format Transformation Data Model Transformation Data Origin Authentication Decomposed Capability Decoupled Contract Direct Authentication Distributed Capability Domain Inventory Dual Protocols Enterprise Inventory Enterprise Service Bus Entity Abstraction Event-Driven Messaging Exception Shielding Federated Endpoint Layer File Gateway Functional Decomposition Intermediate Routing Inventory Endpoint Legacy Wrapper Logic Centralization Message Screening Messaging Metadata Metadata Centralization Multi-Channel Endpoint Non-Agnostic Context Official Endpoint Orchestration Partial State Deferral Partial Validation Policy Centralization Process Abstraction Process Centralization Protocol Bridging Proxy Capability Redundant Implementation Reliable Messaging Rules Centralization Schema Centralization Service Agent Service Broker Service Callback Service Data Replication Service Decomposition Service Encapsulation Service Facade Service Grid Service Instance Routing Service Layers Service Messaging Service Normalization Service Perimeter Guard Service Refactoring State Messaging State Repository Stateful Services Termination Notification Three-Layer Inventory Trusted Subsystem UI Mediator Utility Abstraction Validation Abstraction Version Identification Overview     History     Acknowledgements     Podcasts     Notification Form     Feedback Form     Press Release #1     Press Release #2     Press Release #3 Master SOA Design Pattern Catalog     Master Pattern List (alphabetical)     Master Pattern List (by category)     Master Pattern List with Page Numbers (PDF)     Master Pattern List (Text)     Pattern Notation     Pattern Profiles     Symbol Legend     Pattern Contribution Form SOA Candidate Patterns     SOA Patterns Review Committee     Candidate Patterns Overview     Candidate Patterns List     Candidate Pattern Contribution Form     Candidate Pattern Feedback Form     SOA Pattern Template Design Pattern Basics     What's a Design Pattern?     What's a Design Pattern Language?     What's a Compound Pattern? Supplemental     SOA Patterns and Application Technologies     SOA Design Patterns Historical Influences     SOA Design Patterns and Design Principles     SOA Design Patterns and Design Granularity     Legal Resources     Design Patterns Publications     Reference Posters     SOAPrinciples.com     WhatIsSOA.com     SOA Visio Stencil Dual Protocols (Erl) Home > Inventory Implementataion Patterns > Dual Protocols How can a service inventory overcome the limitations of its canonical protocol while still remaining standardized?   Problem Canonical Protocol requires that all services conform to the use of the same communications technology; however, a single protocol may not be able to accommodate all service requirements, thereby introducing limitations. Solution The service inventory architecture is designed to support services based on primary and secondary protocols. Application Primary and secondary service levels are created and collectively represent the service endpoint layer. All services are subject to standard service-orientation design considerations and specific guidelines are followed to minimize the impact of not following Canonical Protocol. Impacts This pattern can lead to a convoluted inventory architecture, increased governance effort and expense, and (when poorly applied) an unhealthy dependence on Protocol Bridging. Because the endpoint layer is semi-federated, the quantity of potential consumers and reuse opportunities is decreased. Principles Standardized Service Contract, Service Loose Coupling, Service Abstraction, Service Autonomy, Service Composability Architecture Inventory, Service Regardless of protocol, all services must invoke each other via their official service contracts (A, B). Bypassing the contract may seem convenient when the underlying service logic of the primary service supports the same protocol as the secondary service (C), but it is an anti-pattern that will eventually inhibit the application of this pattern and further weaken the overall service inventory foundation. Related Patterns in This Catalog Canonical Protocol (Erl), Concurrent Contracts (Erl), Contract Centralization (Erl), Logic Centralization (Erl), Protocol Bridging (Little, Rischbeck, Simon), Redundant Implementation (Erl) Related Service-Oriented Computing Goals Increased Intrinsic Interoperability, Increased Vendor Diversification Options, Increased Organizational Agility, Reduced IT Burden This page contains excerpts from: SOA Design Patterns by Thomas Erl Foreword by Grady Booch With contributions from David Chappell, Jason Hogg, Anish Karmarkar, Mark Little, David Orchard, Satadru Roy, Thomas Rischbeck, Arnaud Simon, Clemens Utschig, Dennis Wisnosky, and others. (ISBN: 0136135161, Hardcover, Full-Color, 400+ Illustrations, 865 pages) For more information about this book, visit www.soabooks.com.

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