Service-oriented modeling and archi

Service-oriented modeling and architecture
How to identify, specify, and realize services for your SOA
Ali Arsanjani, Ph.D. ([e-mail])
Chief Architect, SOA and Web services Center of Excellence, IBM
09 Nov 2004
This article discusses the highlights of service-oriented modeling
and architecture; the key activities that you need for the analysis
and design required to build a Service-Oriented Architecture (SOA).
The author stresses the importance of addressing the techniques
required for the identification, specification and realization of
services, their flows and composition, as well as the enterprisescale
components needed to realize and ensure the quality of
services required of a SOA.
Introduction
There has been a lot of buzz and hype -- some factual, some not so well-founded
-- surrounding the opportunities presented by Service-oriented Architectures
(SOA) and its implementation as Web services. Analysts have predicted, pundits
have professed, professors have lectured, companies have scurried to sell what
they had, as SOA products -- often missing the point that SOA is not a product.
Itís about bridging the gap between business and IT through a set of businessaligned
IT services using a set of design principles, patterns, and techniques.
ZDNet recently said, "Gartner predicts that by 2008, more than 60 percent of
enterprises will use SOA as a "guiding principle" when creating mission-critical
applications and processes."
A huge demand exists for the development and implementation of SOAs. So if
SOA is not just about the products and standards that help realize it, for example
through Web services, then what additional elements do you need to realize a
SOA? Service-oriented modeling requires additional activities and artifacts that
are not found in traditional object-oriented analysis and design (OOAD). The
article ìElements of Service-oriented Analysis and Design" describes an initial set
of reasons why you need more than OOAD. It also describes how business
process management or enterprise architecture (EA) and OOAD are inadequate
means of conducting analysis and design. Also, in the IBM Redbook entitled
ìPatterns: Service-Oriented Architecture and Web Services", I illustrate the major
activities of this service-oriented modeling approach.
2 29 January 2005
From http://www-128.ibm.com/developerworks/webservices/library/ws-soa-design1/
However, additional important considerations exist that you need to take into
account. For one thing, current OOAD methods do not address the three key
elements of a SOA: services, flows, and components realizing services. You also
need to be able to explicitly address the techniques and processes required for
the identification, specification and realization of services, their flows and
composition, as well as the enterprise-scale components needed to realize and
ensure the quality of services required.
Second, a paradigm shift needs to occur, in order to appreciate the distinct
requirements of the two key roles in a SOA: the service provider and service
consumer. Third, applications assumed to be built for one enterprise or line of
business must now aspire to be used in a supply chain and be exposed to
business partners who might compose, combine, and encapsulate them into new
applications. This is the notion of the service ecosystem or service value-net.
This is a slight step up from just "distributed objects". Itís about the value created
through the network effect: for example, when parties leverage a combination of
Amazon.com with Googleís search services and combine them with eBay
services to build their own hybrid solutions. Or when a travel agency reaches
deep into an airline reservation system and coordinates it with a rental car
agency and hotel chain, updating their records and sending the itinerary to your
electronic organizer. Whatever the application, you need much more than just
good tools and standards to successfully create a SOA. You need some
prescriptive steps to support your SOA life cycle; techniques for the analysis,
design, and realization of services, flows, and components. Therefore, for
anyone interested in enterprise application development, itís crucial to
understand the detailed steps involved in service-oriented modeling and
architecture.
Before I describe these steps in detail, letís first understand what you are aiming
to produce: what is a SOA, and what does it look like? After defining the notion
and concepts behind a SOA, Iíll describe the layers of a SOA and how you need
to record key architectural decisions about each of those layers that help you in
building a blueprint for the SOA that is right for your project, line of business,
enterprise-wide effort, or value-chain that you are trying to integrate and come up
with a set of services, flows, and components that implement the SOA.

Results (Vietnamese) 1:

Mô hình hướng dịch vụ và kiến trúcLàm thế nào để xác định, chỉ định, và thực hiện các dịch vụ cho SOA của bạnAli Arsanjani, tiến sĩ ([e-mail])Dịch vụ kiến trúc sư trưởng, SOA và Web ở trung tâm xuất sắc, IBM09 tháng mười một năm 2004Bài viết này thảo luận về những điểm nổi bật của dịch vụ theo định hướng mô hìnhvà kiến trúc; Các hoạt động quan trọng mà bạn cần cho các phân tíchvà thiết kế cần thiết để xây dựng một kiến trúc Service-Oriented (SOA).Tác giả nhấn mạnh tầm quan trọng của địa chỉ các kỹ thuậtyêu cầu để xác định, đặc điểm kỹ thuật và thực hiện cácDịch vụ, dòng chảy của họ và thành phần, cũng như enterprisescalethành phần cần thiết để nhận ra và đảm bảo chất lượngDịch vụ yêu cầu của một SOA.Giới thiệuĐã có rất nhiều buzz và hype - một số thực tế, một số không phải như vậy tốt thành lập-xung quanh các cơ hội trình bày của kiến trúc hướng dịch vụ(SOA) và thực hiện của nó là dịch vụ Web. Nhà phân tích đã dự đoán, học giảcó công khai, giáo sư đã giảng dạy, công ty có scurried để bán những gìhọ đã có, như là sản phẩm SOA - thường mất điểm SOA đó không phải là một sản phẩm.ITIS về bridging the gap giữa kinh doanh và nó thông qua một tập hợp các businessalignedDịch vụ bằng cách sử dụng một tập hợp các nguyên tắc thiết kế, mô hình, và kỹ thuật.ZDNet mới nói, "Gartner dự báo rằng đến năm 2008, hơn 60 phần trăm củaCác doanh nghiệp sẽ sử dụng SOA là một nguyên tắc hướng dẫn"" khi tạo nhiệm vụ quan trọngapplications and processes."A huge demand exists for the development and implementation of SOAs. So ifSOA is not just about the products and standards that help realize it, for examplethrough Web services, then what additional elements do you need to realize aSOA? Service-oriented modeling requires additional activities and artifacts thatare not found in traditional object-oriented analysis and design (OOAD). Thearticle ìElements of Service-oriented Analysis and Design" describes an initial setof reasons why you need more than OOAD. It also describes how businessprocess management or enterprise architecture (EA) and OOAD are inadequatemeans of conducting analysis and design. Also, in the IBM Redbook entitledìPatterns: Service-Oriented Architecture and Web Services", I illustrate the majoractivities of this service-oriented modeling approach. 2 29 January 2005From http://www-128.ibm.com/developerworks/webservices/library/ws-soa-design1/However, additional important considerations exist that you need to take intoaccount. For one thing, current OOAD methods do not address the three keyelements of a SOA: services, flows, and components realizing services. You alsoneed to be able to explicitly address the techniques and processes required forthe identification, specification and realization of services, their flows andcomposition, as well as the enterprise-scale components needed to realize andensure the quality of services required.Second, a paradigm shift needs to occur, in order to appreciate the distinctrequirements of the two key roles in a SOA: the service provider and serviceconsumer. Third, applications assumed to be built for one enterprise or line ofbusiness must now aspire to be used in a supply chain and be exposed tobusiness partners who might compose, combine, and encapsulate them into newapplications. This is the notion of the service ecosystem or service value-net.This is a slight step up from just "distributed objects". Itís about the value createdthrough the network effect: for example, when parties leverage a combination ofAmazon.com with Googleís search services and combine them with eBayservices to build their own hybrid solutions. Or when a travel agency reachesdeep into an airline reservation system and coordinates it with a rental caragency and hotel chain, updating their records and sending the itinerary to yourelectronic organizer. Whatever the application, you need much more than justgood tools and standards to successfully create a SOA. You need someprescriptive steps to support your SOA life cycle; techniques for the analysis,design, and realization of services, flows, and components. Therefore, foranyone interested in enterprise application development, itís crucial tounderstand the detailed steps involved in service-oriented modeling andarchitecture.Before I describe these steps in detail, letís first understand what you are aimingto produce: what is a SOA, and what does it look like? After defining the notionand concepts behind a SOA, Iíll describe the layers of a SOA and how you needto record key architectural decisions about each of those layers that help you inbuilding a blueprint for the SOA that is right for your project, line of business,enterprise-wide effort, or value-chain that you are trying to integrate and come upwith a set of services, flows, and components that implement the SOA.