System Integration

Hub-and-Spoke Integration Disadvantages

Additional overhead and latency Scalability can be limited because of all burden is on the Hub

SOA Based Integration Advantages

Allows maximum flexibility and reusability; Reduces development cost;

Web Applications Architecture

Web Application Layers: Web Clients Web Server Application Server EIS (database, ERP, ...)

Integration Infrastructure

A collection of common facilities and services to support enterprise integration: Network services Meta-data repository Middleware: containers, messaging, adapters, service bus ... Security services Directory and naming services Job scheduling and management systems System management and monitoring

Elements of Systems Integration

Business Architecture and Domain Subject Architecture and Patterns (Point to point; Hub and spoke; SOA; Sync & Async) Integration Infrastructure (Meta-data; Messaging; Enterprise service bus); Standards and Governance;

Major Components of Web Platform

Client Browser - allow users to consume contents Web Servers - to generate and host contents Connectivity - deliver contents Communications Protocol - allows clients and servers to talk to each other

Why Standards?

Consistence Interchangeability Plug-and-play Support and Maintainability Vendor independence

Hub-and-Spoke Integration Advantages

Decouples sending and receiving applications and allow them to change independently.

Point-to-Point Integration Characteristics

Direct, tightly-coupled connections between two systems; Specialized interface developed for specific purpose; Requires intimate knowledge about format of information to be exchanges.

Characteristics of Integration Architecture

Distributed Computing Standards Components based Reuse and Sharing Decoupling/Loose-Coupling Configurability Extendibility and Scalability

Characteristics of Enterprise Information System (EIS)

Enterprise Grade System Business Critical Impact Multiple Business Units and Processes Requires High Quality of Service Handles Large Volume of Data

Challenges to Systems Integration

Distributed Computing; Multiple Operating Systems; Different Databases; Different Programming Languages; Large Number of Interfaces; Inconsistent Data Types and Formats; Different Application Architecture;

Challenges for system integration

Distributed computing; Multiple OS; Different dB's; Different programing languages; Large number of interfaces; Inconsistent data types and formats; Different application architecture

Levels of Integration - Extended enterprise integration

Enable collaboration beyond enterprise (with partners, suppliers, ...)

Levels of Integration - Application level integration

Enable sustainable interoperations between diverse applications with stable well-defined interfaces

Technical Objectives of Integration

Establish a clear vision and direction for evolution of enterprise systems and technologies; Standardize and streamline enterprise level systems and data architecture; Reduce ripple effects of system changes; Harmonize collaboration and integration between diverse systems and applications; Improve effective utilization of IT resources; Enable agile business via agile IT; Turn IT into a strategic business partner;

Point-to-Point Integration advantages

Fast and efficient

Benefits of Application Servers

Housekeeping services provided by application servers relieve application developers from low level system programming and let them focus on business logic and functionality. Applications can be easily ported between different application server as long as the same standards are followed: written once, run anywhere. This also prevents vendor lock-in. Separate layer offers more flexibility and scalability. Enables effective management and monitoring of enterprise applications and components across the enterprise.

Hub-and-Spoke Integration Characteristics

Hub acts as the middleman (middleware) when applications communicate with each other. Usually implemented with a Message Broker. Centralized monitoring and control because all message transformation, routing, mapping, are done in the Hub.

Importance of bD design

Importance of data; dB design defines the domain of the applications; a well designed dB is critical for the function and performance of applications;

Enterprise Technology Landscape

Infrastructure: Network, data center, HW, BCDR, security, systems management; Enterprise Information Systems; Reporting, data warehouse, data mining, and business intelligence; Middleware and Messaging; Shared services; Client and mobile platforms; Industry specific applications; Governance and policies;

Levels of Integration - Business process integration

Integration and orchestration between different business processes to provide seamlessly unified services to customers

SOA Based Integration Characteristics

Integration processing distributed among end points; Technology independent services allows plug-and-play (Lego); Use of adapters and Enterprise Service Bus (ESB);

Loose-Coupling

Interfaces based on semantics rather than syntax; Conform to standards; Asynchronous integration; Utilize integration middleware;

Classic Problems of IT

Lack of coherent, well defined enterprise architecture; Silos and stovepipes of systems; Redundant data across different systems out of sync; Customized, ad-hoc, point-to-point integrations difficult to reuse; Duplication of functionalities; Error prone manual interventions; Tightly-coupled and monolithic code result in fragile systems that are hard and awkward to change; Lack of standards and processes for technology selection and adoption;

Web Platform Disadvantages

Less functionality compared to fat client/server applications such as rich UI Security concerns

Loose-Coupling benefits

Minimize interdependence among systems; Time; Information format; Technology; Reduce ripple effects and enable plug-and-play.

Point-to-Point Integration disadvantages

Number of connections and complexity grow exponentially; Interdependence causes ripple effects and hard to change; High maintenance cost;

Business Objectives of Integration

Provide unified executive view of enterprise. Provide integrated, streamlined service to customers. Improve operations efficiency by sharing information, resources, and services. Enable business to adapt to changes of market and competitive forces - Faster time-to-market.

Features of Application Servers

Provides runtime environment to enterprise applications and components; Provides capability for managing and monitoring applications and components - deploying, starting, stopping, replication, access control ...; Provides low level system support services such as memory management, logging, transaction, security, etc.; Highly scalability and availability with advanced features such as clustering, load balancing, workload management, and session persistence, etc.

SOA Based Integration Disadvantages

Requires investment and can be hard to make the paradigm shift; Something got to give (performance, limitations);

Advantages of Layered Architecture

Specialization of application components Flexibility of deployment Loose-coupling Scalability

Levels of Integration - Data level integration

Understand semantics and syntax of each data source. Identify redundant and inconsistent data Define standard data dictionary Develop tools for data transformation, sharing, and analysis

Web Platform Advantages

Universal existence of web browsers No need for separate versions for different platforms Central update and maintenance. No client software to distribute, install, and upgrade Extend the traditional corporate boundaries

dB design steps

identify the domain objects, which will be modeled with dB tables; Deciding data elements (data dictionary); define the relations between data objects (ERD); Perform/examine normalization of data relations; Entity=data object=table