ERP Architecture: Why Study Enterprise Systems Architecture?
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Help Help manageme management nt and the imple implemen mentat tation ion teams teams underst understand and in detail detail the the feature featuress and components of the enterprise system. Prov Provid idee a visu visual al repr repres esen enta tati tion on of the the comp comple lex x syst system em inte interf rfac aces es amon among g the the ERP ERP application and databases, operating systems, legacy applications, and networking. Mana Managem gement ent can devel develop op a bette betterr IT plan if the the syst system em infras infrastr truc uctu ture re requ requir irem ement ents, s, trai traini ning ng requi require reme ment nts, s, chang changee mana manage geme ment nt requ requir irem emen ents ts,, and and busi busine ness ss proce process ss reengineering requirements, among others are clarified.
Layered Architecture:
ERP system architecture is organized in layers or tiers to manage system complexity in order to provide scalability scalability and flexibility. flexibility. Traditiona Traditionall ERP architectur architecturee generally generally has three layers, with each responsible for a particular system function. • •
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Data Data Tier Tier (Dat (Dataa Man Manag agem emen ent) t) Business Tier (Business logic of functional modules) Presen Presentat tation ion Tier Tier (End-U (End-User ser Interf Interface ace—GU —GUI) I)
The business tier feeds data into the presentation tier. The data tier focus is on structure of all organizational data and its relationships with both internal and external systems. The busine business/ ss/appl applica icatio tion n tier tier consis consists ts of a Web browse browserr and report reporting ing tool tool where where business processes and end-users interact with the system. Via the presentation tier, a Web-based portal allows users the ability to access and analyze information through their Web browser.
Types of ERP Architecture:
ERP applications are most commonly deployed in a distributed and often widely dispersed manner. While the servers may be centralized, the clients are usually spread to multiple locations throughout the enterprise. Generally there are three functional areas of responsibility that is distributed among the servers and the clients. First, there is the database component - the central repository for all of the data that is transferred to and from the clients. Then, of course, the clients - here raw data gets inputted, requests for information are submitted, and the data satisfying these requests is presented. Lastly, we have the application component that acts as the intermediary between the client and the database. Where these components physically reside and how the processes get distribut distributed ed will vary somewhat from one implement implementation ation to the next. The two most commonly commonly implemented architectures are outlined below. Two-tier Implementations
In typical typical two-tier two-tier architecture, architecture, the server server handles handles both application application and database database duties. duties. The clients are responsible for presenting the data and passing user input back to the server. While there may be multiple servers and the clients may be distributed across several types of local and wide area links, this distribution distribution of processing responsibilities remains remains the same. Some of the benefits are easy to use and access, low cost, high performance.
Three-tier Client/Server Implementations
In three-tier architectures, the database and application functions are separated into independent operating units. This is very typical of large production ERP deployments. In this scenario, satisfying client requests requires two or more network connections. Initially, the client establishes communications with the application server. The application server then creates a second connection to the database server. Some of the benefits are scalability, reliability, flexibility, maintainability, reusability, security.
Web-based architecture:
The Web-based architecture often described as a fourth tier where the Presentation tier is split into Web Services tier and Web Browser tier. End-users have access to ERP applications over the Web. Easily integrate ERP applications with existing systems. Web-based architectures also allow better system-to-system integration. PeopleSoft’s Server-Centric internet architecture.
Service-Oriented Architectures
Also known as object-oriented architectures for Web platforms. Breaks the business tier into smaller, distinct units of services, collectively supporting an ERP functional module. Allows message interaction between any service consumer and service provider. A consumer from a device using any operating system in any language can use this service. Service-oriented architecture separates the service provider from the service consumer.
Generally the architecture of an ERP system influences the cost, maintenance, and the use of the system. If purchased, ERP architecture is often driven by the vendor (Package-Driven Architecture). Two types of ERP architectures: Logical focuses on the supporting needs of the end users. Physical focuses on the efficiency of the system. Logical Architecture of an ERP System:
Physical Architecture of an ERP System:
System Configuration:
Implications for Management
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Enterprise architecture is an important technology for the long-term functioning of the organization.
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ERP architecture decisions are complex because their impact goes beyond systems and technology to people, organizational policy, and business processes.
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ERP architecture must be flexible to support a diverse set of hardware and software platforms.
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Management must learn how to filter out the hyped technologies that do not provide value to their organization.
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Top management must therefore be involved in designing the architecture from the very beginning of the ERP implementation project.
