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{{other uses|Enterprise integration}}
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'''Enterprise application integration (EAI)''' is the use of [[software]] and computer systems architectural principles to integrate a set of enterprise computer applications.
 
== Overview ==
Enterprise application integration is an integration framework composed of a collection of technologies and services which form a [[Middleware (distributed applications)|middleware]] to enable integration of systems and applications across the enterprise.
 
[[Supply chain management]] applications (for managing inventory and shipping), [[customer relationship management]] applications (for managing current and potential customers), [[business intelligence]] applications (for finding patterns from existing data from operations), and other types of applications (for managing data such as [[human resources]] data, health care, internal communications, etc.) typically cannot communicate with one another in order to share data or business rules. For this reason, such applications are sometimes referred to as [[islands of automation]] or [[information silo]]s. This lack of communication leads to inefficiencies, wherein identical data are stored in multiple locations, or straightforward processes are unable to be automated.
 
Enterprise application integration is the process of linking such applications within a single organization together in order to simplify and automate business processes to the greatest extent possible, while at the same time avoiding having to make sweeping changes to the existing applications or data structures. In the words of the [[Gartner Group]], EAI is the “unrestricted sharing of data and business processes among any connected application or data sources in the enterprise.”<ref>In its April 2001 report for AIIM International, "Enterprise Applications: Adoption of E-Business and Document Technologies, 2000–2001: Worldwide Industry Study," Gartner defines EAI as "the unrestricted sharing of data and business processes among any connected applications and data sources in the enterprise."<br />{{cite journal |url=http://findarticles.com/p/articles/mi_qa3937/is_200203/ai_n9019202 |title=Enterprise application integration |journal=Information Management Journal |date=March/April 2002 |last=Gable |first=Julie |accessdate=2008-01-22 }}</ref>
 
One large challenge of EAI is that the various systems that need to be linked together often reside on different [[operating system]]s, use different [[database]] solutions and different [[computer language]]s, and in some cases are [[legacy system]]s that are no longer supported by the vendor who originally created them. In some cases, such systems are dubbed "[[stovepipe system]]s" because they consist of components that have been jammed together in a way that makes it very hard to modify them in any way.
 
== Improving connectivity ==
 
If integration is applied without following a structured EAI approach, [[Link (telecommunications)#Point-to-point|point-to-point connections]] grow across an organization. Dependencies are added on an impromptu basis, resulting in a complex structure that is difficult to maintain. This is commonly referred to as spaghetti, an allusion to the programming equivalent of [[spaghetti code]]. For example:
 
The number of connections needed to have fully meshed point-to-point connections, with <math>n</math> points, is given by <math>\frac{n(n-1)}{2}</math>. Thus, for ten applications to be fully integrated point-to-point, <math>\frac{10\times9}{2}</math>, or 45 point-to-point connections are needed.
 
However, EAI is not just about sharing data between applications; it focuses on sharing both business data and business process. [[Middleware analyst]]s attending to EAI involves looking at the [[system of systems]], which involves large scale [[inter-disciplinary]] problems with multiple, [[heterogeneous]], distributed [[systems]] that are embedded in [[computer networking|networks]] at multiple levels. One of the biggest mistakes that organizations make to solve this problem is excessively focusing on low-level bottom-up IT approaches, often driven from development-oriented technical teams. In contrast, a paradigm shift is emerging to start EAI rationalization efforts with effective top-down business-oriented analysis found in disciplines such as Enterprise Architecture, Business Architecture, and Business Process Management. The business oriented approach can enable a cohesive business integration strategy which is supported by, instead of dictated by, technical and data integration strategies.
 
== Purposes ==
EAI can be used for different purposes:
 
*[[Data integration]]: Ensures that information in multiple systems is kept consistent. This is also known as [[enterprise information integration]] (EII).
*Vendor independence: Extracts business policies or rules from applications and implements them in the EAI system, so that even if one of the business applications is replaced with a different vendor's application, the business rules do not have to be re-implemented.
*Common facade: An EAI system can front-end a cluster of applications, providing a single consistent access interface to these applications and shielding users from having to learn to use different software packages.
 
== Patterns ==
 
=== Integration patterns ===
There are two patterns that EAI systems implement:
 
;[[Data mediation|Mediation]] (intra-communication):Here, the EAI system acts as the go-between or broker between multiple applications. Whenever an interesting event occurs in an application (for instance, new information is created or a new transaction completed) an integration module in the EAI system is notified. The module then propagates the changes to other relevant applications.
;[[Federation (information technology)|Federation]] (inter-communication):In this case, the EAI system acts as the overarching facade across multiple applications. All event calls from the 'outside world' to any of the applications are front-ended by the EAI system. The EAI system is configured to expose only the relevant information and interfaces of the underlying applications to the outside world, and performs all interactions with the underlying applications on behalf of the requester.
 
Both patterns are often used concurrently. The same EAI system could be keeping multiple applications in sync (mediation), while servicing requests from external users against these applications (federation).
 
=== Access patterns ===
EAI supports both asynchronous and synchronous access patterns, the former being typical in the mediation case and the latter in the federation case.
 
=== Lifetime patterns ===
An integration operation could be short-lived (e.g. keeping data in sync across two applications could be completed within a second) or long-lived (e.g. one of the steps could involve the EAI system interacting with a human [[work flow]] application for approval of a loan that takes hours or days to complete).
 
== Topologies ==
There are two major topologies: [[Hub and spoke|hub-and-spoke]], and [[Enterprise service bus|bus]]. Each has its own advantages and disadvantages. In the hub-and-spoke model, the EAI system is at the center (the hub), and interacts with the applications via the spokes. In the bus model, the EAI system is the bus (or is implemented as a resident module in an already existing message bus or [[message-oriented middleware]]).
 
== Technologies ==
Multiple technologies are used in implementing each of the components of the EAI system:
 
;Bus/hub: This is usually implemented by enhancing standard middleware products ([[application server]], message bus) or implemented as a stand-alone program (i.&nbsp;e., does not use any middleware), acting as its own middleware.
;Application connectivity: The bus/hub connects to applications through a set of '''adapters''' (also referred to as '''connectors'''). These are programs that know how to interact with an underlying business application. The adapter performs two-way communication, performing requests from the hub against the application, and notifying the hub when an event of interest occurs in the application (a new record inserted, a transaction completed, etc.). Adapters can be specific to an application (e.&nbsp;g., built against the application vendor's client libraries) or specific to a class of applications (e.&nbsp;g., can interact with any application through a standard communication protocol, such as [[SOAP]], [[SMTP]] or [[Action Message Format]] (AMF)). The adapter could reside in the same process space as the bus/hub or execute in a remote location and interact with the hub/bus through industry standard protocols such as message queues, web services, or even use a proprietary protocol. In the Java world, standards such as [[J2EE Connector Architecture|JCA]] allow adapters to be created in a vendor-neutral manner.
;[[File format|Data format]] and [[data transformation|transformation]]: To avoid every adapter having to convert data to/from every other applications' formats, EAI systems usually stipulate an application-independent (or common) data format. The EAI system usually provides a data transformation service as well to help convert between application-specific and common formats. This is done in two steps: the adapter converts information from the application's format to the bus's common format. Then, semantic transformations are applied on this (converting zip codes to city names, splitting/merging objects from one application into objects in the other applications, and so on).
;Integration modules: An EAI system could be participating in multiple concurrent integration operations at any given time, each type of integration being processed by a different integration module. Integration modules subscribe to events of specific types and process notifications that they receive when these events occur. These modules could be implemented in different ways: on [[Java (programming language)|Java]]-based EAI systems, these could be [[web application]]s or [[Enterprise JavaBean|EJBs]] or even [[POJO]]s that conform to the EAI system's specifications.
;Support for [[Database transaction|transaction]]s: When used for process integration, the EAI system also provides transactional consistency across applications by executing all integration operations across all applications in a single overarching distributed transaction (using [[two-phase commit protocol]]s or [[compensating transaction]]s).
 
== Communication architectures ==
Currently, there are many variations of thought on what constitutes the best infrastructure, component model, and standards structure for Enterprise Application Integration. There seems to be consensus that four components are essential for a modern enterprise application integration architecture:
 
#A centralized broker that handles security, access, and communication. This can be accomplished through integration servers (like the [[Schools Interoperability Framework|School Interoperability Framework (SIF)]] Zone Integration Servers) or through similar software like the [[enterprise service bus]] (ESB) model that acts as a SOAP-oriented services manager.
#An independent data model based on a standard data structure, also known as a [[Canonical Model|canonical data model]]. It appears that XML and the use of XML style sheets has become the ''[[de facto]]'' and in some cases ''[[de jure]]'' standard for this uniform business language.
#A connector, or agent model where each vendor, application, or interface can build a single component that can speak natively to that application and communicate with the centralized broker.
#A system model that defines the APIs, data flow and rules of engagement to the system such that components can be built to interface with it in a standardized way.
 
Although other approaches like connecting at the database or user-interface level have been explored, they have not been found to scale or be able to adjust. Individual applications can publish messages to the centralized broker and subscribe to receive certain messages from that broker. Each application only requires one connection to the broker. This central control approach can be extremely [[scalable]] and [[Event-driven SOA|highly evolvable]].
 
Enterprise Application Integration is related to middleware technologies such as message-oriented middleware ([[message-oriented middleware|MOM]]), and data representation technologies such as [[XML]]. Other EAI technologies involve using [[web service]]s as part of [[service-oriented architecture]] as a means of integration. Enterprise Application Integration tends to be data centric. In the near future, it will come to include [[Enterprise Content Integration|content integration]] and [[business process]]es.
 
== Implementation pitfalls ==
In 2003 it was reported that 70% of all EAI projects fail. Most of these failures are not due to the software itself or technical difficulties, but due to management issues. Integration Consortium European Chairman Steve Craggs has outlined the seven main pitfalls undertaken by companies using EAI systems and explains solutions to these problems.<ref>{{cite web|title=Dancing Around EAI 'Bear Traps'|date=2003-12-15|first=Gian|last=Trotta|url=http://www.ebizq.net/topics/int_sbp/features/3463.html|accessdate=2006-06-27}}</ref>
 
#Constant change: The very nature of EAI is dynamic and requires dynamic project managers to manage their implementation.
#Shortage of [[middleware analyst|EAI expert]]s: EAI requires knowledge of many issues and technical aspects.
#Competing standards: Within the EAI field, the paradox is that EAI standards themselves are not universal.
#EAI is a tool paradigm: EAI is not a tool, but rather a system and should be implemented as such.
#Building interfaces is an art: Engineering the solution is not sufficient. Solutions need to be negotiated with user departments to reach a common consensus on the final outcome. A lack of consensus on interface designs leads to excessive effort to map between various systems data requirements.
#Loss of detail: Information that seemed unimportant at an earlier stage may become crucial later.
#Accountability: Since so many departments have many conflicting requirements, there should be clear accountability for the system's final structure.
#Lack of centralized co-ordination of EAI work.<ref>{{cite web|title=Avoiding Pitfalls of Integration Competency Centers|date=2013-10-25|first=Antti|last=Toivanen|url=http://integrationwarstories.com/2013/10/25/avoiding-pitfalls-of-integration-competency-centers/}}</ref>
 
Other potential problems may arise in these areas:
*Emerging Requirements: EAI implementations should be extensible and modular to allow for future changes.
*Protectionism: The applications whose data is being integrated often belong to different departments that have technical, cultural, and political reasons for not wanting to share their data with other departments
 
== Future ==
 
Integration market is growing due to the "best-of-breed" thinking in buying new CRMs, ERPs and other enterprise systems. Instead of consolidating everything to one big ERP, specialized systems are used to serve business better. This has led to increase in integration market as the systems are more and more heterogeneous. Another driver is current [[cloud computing]] adoption. "Best-of-breed" -buying pattern and cloud adoption go nicely hand-in-hand as it is easy to deliver specialized best-of-breed solutions via cloud.
 
Cloud also leverages the integration markets to smaller companies than before as new system can be bought as a service instead of large investment in the beginning. Cloud services are mostly [[Multitenancy|multi-tenant]] - which allows cloud service providers to offer them with less costs per user.<ref>{{cite web|title=Future of EAI|date=2013-10-27|first=Antti|last=Toivanen|url=http://integrationwarstories.com/2013/10/27/future-of-eai/}}</ref>
 
== See also ==
*[[Enterprise architecture framework]]
*[[Business semantics management]]
*[[Data integration]]
*[[Enterprise information integration]]
*[[Enterprise integration]]
*[[Enterprise Integration Patterns]]
*[[Enterprise service bus]]
*[[Generalised Enterprise Reference Architecture and Methodology]]
*[[Integration appliance]]
*[[Integration competency center]]
*[[Integration platform]]
*[[Straight through processing]]
*[[System integration]]
 
=== Initiatives and organizations ===
*[[Health Level 7]]
*[[Open Knowledge Initiative]]
*[[OSS through Java]]
*[[Schools Interoperability Framework]] (SIF)
 
=== Commercial products ===
*[[Adeptia]] ESB Suite
*[[Amtrix]]
*[[Informatica]] Cloud Data Integration
*[[WebSphere Message Broker|IBM WebSphere Message Broker]]
*[[Information Builders]] iWay ISM
*[[Intersystems]] Ensemble
*[[Jitterbit Integration Server]]
*[[Magic Software Enterprises|Magic Software xpi Integration Platform]]
*[[Microsoft BizTalk Server]]
*[[Mule (software)|Mule Enterprise]]
*[[Oracle SOA Suite]]
*[[SAP AG|SAP]] NetWeaver Process Integration (PI)
*[[SnapLogic]]
*[[Tibco Software|Tibco ActiveMatrix/Business Works]]
*[[WebMethods]]
 
=== Open-source projects ===
*[[UltraESB]]
*[[Apache ActiveMQ]]
*[[Mule ESB]]
*[[Apache Camel]]
*[[Guaraná DSL]]
*[[Apache ServiceMix]]
*[[Apache Synapse]]
*[[Fuse ESB]] (based on Apache ServiceMix)
*[[Fuse Mediation Router]] (based on Apache Camel)
*[[Fuse Message Broker]] (based on Apache ActiveMQ)
*[[MuleSoft]]
*[[Niklas Integration Platform]]
*[[Openadaptor]]
*[[OpenESB]]
*[[Petals ESB]]
*[[Talend]]
*[[Virtuoso Universal Server]]
 
== References ==
<references/>
 
<!-- Categories -->
[[Category:Enterprise application integration]]

Revision as of 20:23, 12 February 2014

I like Driving. Appears boring? Not!
I also to learn Norwegian in my spare time.

Feel free to surf to my weblog; Crazy Taxi City Rush Hack