Middleware
Encyclopedia
Middleware is computer
software that connects software components or people and their applications. The software consists of a set of services that allows multiple processes running on one or more machines to interact. This technology evolved to provide for interoperability
in support of the move to coherent distributed architectures, which are most often used to support and simplify complex distributed application
s. It includes web server
s, application server
s, and similar tools that support application development and delivery. Middleware is especially integral to modern information technology based on XML
, SOAP
, Web service
s, and service-oriented architecture
.
Middleware sits "in the middle" between application software
that may be working on different operating system
s. It is similar to the middle layer of a three-tier
single system architecture, except that it is stretched across multiple systems or applications. Examples include EAI
software, telecommunications software, transaction monitors
, and messaging-and-queueing software.
The distinction between operating system and middleware functionality is, to some extent, arbitrary. While core kernel functionality can only be provided by the operating system itself, some functionality previously provided by separately sold middleware is now integrated in operating systems. A typical example is the TCP/IP stack for telecommunications, nowadays included in virtually every operating system.
In simulation technology, middleware is generally used in the context of the high level architecture (HLA) that applies to many distributed simulations. It is a layer of software that lies between the application code and the run-time infrastructure. Middleware generally consists of a library of functions, and enables a number of applications–simulations or federates in HLA terminology—to page
these functions from the common library rather than re-create them for each application.
and data integration
software.
ObjectWeb defines middleware as: "The software layer that lies between the operating system
and applications on each side of a distributed computing system in a network."
, Red Hat
, Oracle Corporation
and Microsoft
are major vendors providing middleware software. Vendors such as Axway, SAP
, TIBCO, Informatica
, Pervasive
and webMethods
were specifically founded to provide Web
-oriented middleware tools. Groups such as the Apache Software Foundation
, OpenSAF
and the ObjectWeb Consortium
(now OW2) encourage the development of open source
middleware. Microsoft .NET “Framework” architecture is essentially “Middleware” with typical middleware functions distributed between the various products, with most inter-computer interaction by industry standards, open APIs or RAND software licence. Solace Systems
provides middleware in purpose-built hardware for implementations that may experience scale or speed limitations when using software.
s to allow an application to:
when compared to the operating system and network services.
Middleware offers some unique technological advantages for business and industry. For example, traditional database systems are usually deployed in closed environments where users access the system only via a restricted network or intranet
(e.g., an enterprise’s internal network). With the phenomenal growth of the World Wide Web
, users can access virtually any database for which they have proper access rights from anywhere in the world. Middleware addresses the problem of varying levels of interoperability
among different database structures. Middleware facilitates transparent access to legacy database management system
s (DBMSs) or applications via a web server
without regard to database-specific characteristics.
Businesses frequently use middleware applications to link information from departmental databases, such as payroll, sales, and accounting, or databases housed in multiple geographic locations. In the highly competitive healthcare community, laboratories make extensive use of middleware applications for data mining
, laboratory information system
(LIS) backup, and to combine systems during hospital mergers. Middleware helps bridge the gap between separate LISs in a newly formed healthcare network following a hospital buyout.
Wireless networking developers can use middleware to meet the challenges associated with wireless sensor network
(WSN), or WSN technologies. Implementing a middleware application allows WSN developers to integrate operating systems and hardware with the wide variety of various applications that are currently available.
Middleware can help software developers avoid having to write application programming interface
s (API) for every control program, by serving as an independent programming interface for their applications.
For Future Internet
network operation through traffic monitoring in multi-domain scenarios
, using mediator tools (middleware) is a powerful help since they allow operators
, searchers and service providers to supervise Quality of service
and analyse eventual failures in telecommunication services.
Finally, e-commerce uses middleware to assist in handling rapid and secure transactions over many different types of computer environments. In short, middleware has become a critical element across a broad range of industries, thanks to its ability to bring together resources across dissimilar networks or computing platforms.
In 2004 members of the European Broadcasting Union
(EBU) carried out a study of Middleware with respect to system integration in broadcast environments. This involved system design engineering experts from 10 major European broadcasters working over a 12 month period to understand the effect of predominantly software based products to media production and broadcasting system design techniques. The resulting reports Tech 3300 and Tech 3300s were published and are freely available from the EBU web site.
(MOM) is middleware where transactions or event notifications are delivered between disparate systems or components by way of messages, often via an enterprise messaging system
. With MOM, messages sent to the client are collected and stored until they are acted upon, while the client continues with other processing.
is a type of middleware that facilitates message passing between disparate systems or components in standard formats, often using XML
, SOAP
or web services.
Part of an enterprise messaging system
, message broker software may queue, duplicate, translate and deliver messages to disparate systems or components in a messaging system.
(ESB) is defined by the Burton Group as "some type of integration middleware product that supports both MOM
and Web services".
(IMW) provides real-time intelligence and event management through intelligent agents. The IMW manages the real-time processing of high volume sensor signals and turns these signals into intelligent and actionable business information. The actionable information is then delivered in end-user power dashboards to individual users or is pushed to systems within or outside the enterprise. It is able to support various heterogeneous types of hardware and software and provides an API for interfacing with external systems. It should have a highly scalable, distributed architecture which embeds intelligence throughout the network to transform raw data systematically into actionable and relevant knowledge. It can also be packaged with tools to view and manage operations and build advanced network applications most effectively.
middleware, as well as the Content-centric networking
paradigm.
middleware, a client makes calls to procedures running on remote systems. Can be asynchronous or synchronous
.
middleware, it is possible for applications to send objects and request services in an object-oriented system.
Computer
A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...
software that connects software components or people and their applications. The software consists of a set of services that allows multiple processes running on one or more machines to interact. This technology evolved to provide for interoperability
Interoperability
Interoperability is a property referring to the ability of diverse systems and organizations to work together . The term is often used in a technical systems engineering sense, or alternatively in a broad sense, taking into account social, political, and organizational factors that impact system to...
in support of the move to coherent distributed architectures, which are most often used to support and simplify complex distributed application
Distributed application
-Introduction:Where classic software systems of the past century were mostly based on Client–server models and Client-centric application development, both ultimately run on one single computer, be it the client computer or the server....
s. It includes web server
Web server
Web server can refer to either the hardware or the software that helps to deliver content that can be accessed through the Internet....
s, application server
Application server
An application server is a software framework that provides an environment in which applications can run, no matter what the applications are or what they do...
s, and similar tools that support application development and delivery. Middleware is especially integral to modern information technology based on XML
XML
Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....
, SOAP
SOAP
SOAP, originally defined as Simple Object Access Protocol, is a protocol specification for exchanging structured information in the implementation of Web Services in computer networks...
, Web service
Web service
A Web service is a method of communication between two electronic devices over the web.The W3C defines a "Web service" as "a software system designed to support interoperable machine-to-machine interaction over a network". It has an interface described in a machine-processable format...
s, and service-oriented architecture
Service-oriented architecture
In software engineering, a Service-Oriented Architecture is a set of principles and methodologies for designing and developing software in the form of interoperable services. These services are well-defined business functionalities that are built as software components that can be reused for...
.
Middleware sits "in the middle" between application software
Application software
Application software, also known as an application or an "app", is computer software designed to help the user to perform specific tasks. Examples include enterprise software, accounting software, office suites, graphics software and media players. Many application programs deal principally with...
that may be working on different operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
s. It is similar to the middle layer of a three-tier
Multitier architecture
In software engineering, multi-tier architecture is a client–server architecture in which the presentation, the application processing, and the data management are logically separate processes. For example, an application that uses middleware to service data requests between a user and a database...
single system architecture, except that it is stretched across multiple systems or applications. Examples include EAI
Enterprise application integration
Enterprise Application Integration is defined as the use of software and computer systems architectural principles to integrate a set of enterprise computer applications.- Overview :...
software, telecommunications software, transaction monitors
Transaction Processing System
A transaction processing system is a type of information system. TPSs collect, store, modify, and retrieve the transactions of an organization. A transaction is an event that generates or modifies data that is eventually stored in an information system. To be considered a transaction processing...
, and messaging-and-queueing software.
The distinction between operating system and middleware functionality is, to some extent, arbitrary. While core kernel functionality can only be provided by the operating system itself, some functionality previously provided by separately sold middleware is now integrated in operating systems. A typical example is the TCP/IP stack for telecommunications, nowadays included in virtually every operating system.
In simulation technology, middleware is generally used in the context of the high level architecture (HLA) that applies to many distributed simulations. It is a layer of software that lies between the application code and the run-time infrastructure. Middleware generally consists of a library of functions, and enables a number of applications–simulations or federates in HLA terminology—to page
Paging
In computer operating systems, paging is one of the memory-management schemes by which a computer can store and retrieve data from secondary storage for use in main memory. In the paging memory-management scheme, the operating system retrieves data from secondary storage in same-size blocks called...
these functions from the common library rather than re-create them for each application.
Definitions
Software that provides a link between separate software applications. Middleware is sometimes called plumbing because it connects two applications and passes data between them. Middleware allows data contained in one database to be accessed through another. This definition would fit enterprise application integrationEnterprise application integration
Enterprise Application Integration is defined as the use of software and computer systems architectural principles to integrate a set of enterprise computer applications.- Overview :...
and data integration
Data integration
Data integration involves combining data residing in different sources and providing users with a unified view of these data.This process becomes significant in a variety of situations, which include both commercial and scientific domains...
software.
ObjectWeb defines middleware as: "The software layer that lies between the operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
and applications on each side of a distributed computing system in a network."
Origins
Middleware is a relatively new addition to the computing landscape. It gained popularity in the 1980s as a solution to the problem of how to link newer applications to older legacy systems, although the term had been in use since 1968. It also facilitated distributed processing, the connection of multiple applications to create a larger application, usually over a network.Organizations
IBMIBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
, Red Hat
Red Hat
Red Hat, Inc. is an S&P 500 company in the free and open source software sector, and a major Linux distribution vendor. Founded in 1993, Red Hat has its corporate headquarters in Raleigh, North Carolina with satellite offices worldwide....
, Oracle Corporation
Oracle Corporation
Oracle Corporation is an American multinational computer technology corporation that specializes in developing and marketing hardware systems and enterprise software products – particularly database management systems...
and Microsoft
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
are major vendors providing middleware software. Vendors such as Axway, SAP
SAP AG
SAP AG is a German software corporation that makes enterprise software to manage business operations and customer relations. Headquartered in Walldorf, Baden-Württemberg, with regional offices around the world, SAP is the market leader in enterprise application software...
, TIBCO, Informatica
Informatica
Informatica Corporation is a NASDAQ listed company with ticker INFA. Founded in 1993, its headquarters is in Redwood City, California. Founded by Diaz Nesamoney and Gaurav Dhillon...
, Pervasive
Pervasive Software
Pervasive Software develops and distributes data infrastructure software and ETL tools that integrate, analyze, secure, manage and harvest data from disparate sources. Pervasive Data Integrator and Pervasive Data Profiler are the flagship integration products, and the Pervasive PSQL relational...
and webMethods
WebMethods
webMethods is an enterprise software company, acquired by Software AG, focused on application integration, business process integration and B2B partner integration. Founded in 1996, the company pioneered the use of web services to connect software applications together within a single organization...
were specifically founded to provide Web
World Wide Web
The World Wide Web is a system of interlinked hypertext documents accessed via the Internet...
-oriented middleware tools. Groups such as the Apache Software Foundation
Apache Software Foundation
The Apache Software Foundation is a non-profit corporation to support Apache software projects, including the Apache HTTP Server. The ASF was formed from the Apache Group and incorporated in Delaware, U.S., in June 1999.The Apache Software Foundation is a decentralized community of developers...
, OpenSAF
Opensaf
OpenSAF is an Open Source Project established to develop High Availability middleware consistent with specifications, under the LGPLv2.1 license. The OpenSAF Foundation was established by leading Communications and Enterprise Computing Companies to facilitate the OpenSAF Project and to accelerate...
and the ObjectWeb Consortium
ObjectWeb
The OW2 Consortium is a not-for-profit, international consortium mainly devoted to producing open source middleware, EAI, e-business, clustering, grid computing. It was founded by INRIA, Groupe Bull, and France Télécom...
(now OW2) encourage the development of open source
Open source
The term open source describes practices in production and development that promote access to the end product's source materials. Some consider open source a philosophy, others consider it a pragmatic methodology...
middleware. Microsoft .NET “Framework” architecture is essentially “Middleware” with typical middleware functions distributed between the various products, with most inter-computer interaction by industry standards, open APIs or RAND software licence. Solace Systems
Solace systems
Solace Systems is a content networking company based in Kanata, Ontario, Canada that manufactures and sells middleware appliances. Middleware appliances are rack-mountable network devices that implement message-oriented middleware and content-based routing in purpose-built hardware...
provides middleware in purpose-built hardware for implementations that may experience scale or speed limitations when using software.
Use of middleware
Middleware services provide a more functional set of application programming interfaceApplication programming interface
An application programming interface is a source code based specification intended to be used as an interface by software components to communicate with each other...
s to allow an application to:
- Locate transparently across the network, thus providing interaction with another service or application
- Filter data to make them friendly usable or public via anonymization process for privacy protection (for example)
- Be independent from network services
- Be reliable and always available
- Add complementary attributes like semanticsSemanticsSemantics is the study of meaning. It focuses on the relation between signifiers, such as words, phrases, signs and symbols, and what they stand for, their denotata....
when compared to the operating system and network services.
Middleware offers some unique technological advantages for business and industry. For example, traditional database systems are usually deployed in closed environments where users access the system only via a restricted network or intranet
Intranet
An intranet is a computer network that uses Internet Protocol technology to securely share any part of an organization's information or network operating system within that organization. The term is used in contrast to internet, a network between organizations, and instead refers to a network...
(e.g., an enterprise’s internal network). With the phenomenal growth of the World Wide Web
World Wide Web
The World Wide Web is a system of interlinked hypertext documents accessed via the Internet...
, users can access virtually any database for which they have proper access rights from anywhere in the world. Middleware addresses the problem of varying levels of interoperability
Interoperability
Interoperability is a property referring to the ability of diverse systems and organizations to work together . The term is often used in a technical systems engineering sense, or alternatively in a broad sense, taking into account social, political, and organizational factors that impact system to...
among different database structures. Middleware facilitates transparent access to legacy database management system
Database management system
A database management system is a software package with computer programs that control the creation, maintenance, and use of a database. It allows organizations to conveniently develop databases for various applications by database administrators and other specialists. A database is an integrated...
s (DBMSs) or applications via a web server
Web server
Web server can refer to either the hardware or the software that helps to deliver content that can be accessed through the Internet....
without regard to database-specific characteristics.
Businesses frequently use middleware applications to link information from departmental databases, such as payroll, sales, and accounting, or databases housed in multiple geographic locations. In the highly competitive healthcare community, laboratories make extensive use of middleware applications for data mining
Data mining
Data mining , a relatively young and interdisciplinary field of computer science is the process of discovering new patterns from large data sets involving methods at the intersection of artificial intelligence, machine learning, statistics and database systems...
, laboratory information system
Laboratory information system
A lab information system is a class of software that receives, processes, and stores information generated by medical laboratory processes. These systems often must interface with instruments and other information systems such as hospital information systems...
(LIS) backup, and to combine systems during hospital mergers. Middleware helps bridge the gap between separate LISs in a newly formed healthcare network following a hospital buyout.
Wireless networking developers can use middleware to meet the challenges associated with wireless sensor network
Wireless sensor network
A wireless sensor network consists of spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperature, sound, vibration, pressure, motion or pollutants and to cooperatively pass their data through the network to a main location. The more modern...
(WSN), or WSN technologies. Implementing a middleware application allows WSN developers to integrate operating systems and hardware with the wide variety of various applications that are currently available.
Middleware can help software developers avoid having to write application programming interface
Application programming interface
An application programming interface is a source code based specification intended to be used as an interface by software components to communicate with each other...
s (API) for every control program, by serving as an independent programming interface for their applications.
For Future Internet
Future Internet
Future Internet is a general term for research activities on new architectures for the Internet.-History:While the technical development of the Internet has been an extensive research topic from the beginning, an increased public awareness of several critical shortcomings in terms of performance,...
network operation through traffic monitoring in multi-domain scenarios
Network management
Network management refers to the activities, methods, procedures, and tools that pertain to the operation, administration, maintenance, and provisioning of networked systems....
, using mediator tools (middleware) is a powerful help since they allow operators
Telecommunications Service Provider
A telecommunications service provider or TSP is a type of communications service provider that has traditionally provided telephone and similar services...
, searchers and service providers to supervise Quality of service
Quality of service
The quality of service refers to several related aspects of telephony and computer networks that allow the transport of traffic with special requirements...
and analyse eventual failures in telecommunication services.
Finally, e-commerce uses middleware to assist in handling rapid and secure transactions over many different types of computer environments. In short, middleware has become a critical element across a broad range of industries, thanks to its ability to bring together resources across dissimilar networks or computing platforms.
In 2004 members of the European Broadcasting Union
European Broadcasting Union
The European Broadcasting Union is a confederation of 74 broadcasting organisations from 56 countries, and 49 associate broadcasters from a further 25...
(EBU) carried out a study of Middleware with respect to system integration in broadcast environments. This involved system design engineering experts from 10 major European broadcasters working over a 12 month period to understand the effect of predominantly software based products to media production and broadcasting system design techniques. The resulting reports Tech 3300 and Tech 3300s were published and are freely available from the EBU web site.
Message-Oriented Middleware
Message-Oriented MiddlewareMessage-oriented middleware
Message-oriented middleware is software or hardware infrastructure supporting sending and receiving messages between distributed systems. MOM allows application modules to be distributed over heterogeneous platforms and reduces the complexity of developing applications that span multiple...
(MOM) is middleware where transactions or event notifications are delivered between disparate systems or components by way of messages, often via an enterprise messaging system
Enterprise messaging system
An enterprise messaging system is a set of published Enterprise-wide standards that allows organizations to send semantically precise messages between computer systems. EMS systems promote loosely coupled architectures that allow changes in the formats of messages to have minimum impact on...
. With MOM, messages sent to the client are collected and stored until they are acted upon, while the client continues with other processing.
Enterprise messaging system
An enterprise messaging systemEnterprise messaging system
An enterprise messaging system is a set of published Enterprise-wide standards that allows organizations to send semantically precise messages between computer systems. EMS systems promote loosely coupled architectures that allow changes in the formats of messages to have minimum impact on...
is a type of middleware that facilitates message passing between disparate systems or components in standard formats, often using XML
XML
Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....
, SOAP
SOAP
SOAP, originally defined as Simple Object Access Protocol, is a protocol specification for exchanging structured information in the implementation of Web Services in computer networks...
or web services.
Message broker
Part of an enterprise messaging system
Enterprise messaging system
An enterprise messaging system is a set of published Enterprise-wide standards that allows organizations to send semantically precise messages between computer systems. EMS systems promote loosely coupled architectures that allow changes in the formats of messages to have minimum impact on...
, message broker software may queue, duplicate, translate and deliver messages to disparate systems or components in a messaging system.
Enterprise Service Bus
Enterprise Service BusEnterprise service bus
An enterprise service bus is a software architecture model used for designing and implementing the interaction and communication between mutually interacting software applications in Service Oriented Architecture...
(ESB) is defined by the Burton Group as "some type of integration middleware product that supports both MOM
Message-oriented middleware
Message-oriented middleware is software or hardware infrastructure supporting sending and receiving messages between distributed systems. MOM allows application modules to be distributed over heterogeneous platforms and reduces the complexity of developing applications that span multiple...
and Web services".
Intelligent Middleware
Intelligent MiddlewareMiddleware
Middleware is computer software that connects software components or people and their applications. The software consists of a set of services that allows multiple processes running on one or more machines to interact...
(IMW) provides real-time intelligence and event management through intelligent agents. The IMW manages the real-time processing of high volume sensor signals and turns these signals into intelligent and actionable business information. The actionable information is then delivered in end-user power dashboards to individual users or is pushed to systems within or outside the enterprise. It is able to support various heterogeneous types of hardware and software and provides an API for interfacing with external systems. It should have a highly scalable, distributed architecture which embeds intelligence throughout the network to transform raw data systematically into actionable and relevant knowledge. It can also be packaged with tools to view and manage operations and build advanced network applications most effectively.
Content-Centric Middleware
Content-centric middleware provides a simple provide/consume abstraction through which applications can issue requests for uniquely identified content, without worrying about where or how it is obtained. Juno is one example, which allows applications to generate content requests associated with high-level delivery requirements. The middleware then adapts the underlying delivery to access the content from the source(s) that are best suited to matching the requirements. This is therefore similar to Publish/subscribePublish/subscribe
Publish–subscribe is a messaging pattern where senders of messages, called publishers, do not program the messages to be sent directly to specific receivers, called subscribers. Published messages are characterized into classes, without knowledge of what, if any, subscribers there may be...
middleware, as well as the Content-centric networking
Content-centric networking
Content-centric networking is an alternative approach to the architecture of computer networks...
paradigm.
Hurwitz classification system
Judith Hurwitz created a classification system for middleware in her article Sorting Out Middleware.Remote Procedure Call
With Remote Procedure CallRemote procedure call
In computer science, a remote procedure call is an inter-process communication that allows a computer program to cause a subroutine or procedure to execute in another address space without the programmer explicitly coding the details for this remote interaction...
middleware, a client makes calls to procedures running on remote systems. Can be asynchronous or synchronous
Synchronization (computer science)
In computer science, synchronization refers to one of two distinct but related concepts: synchronization of processes, and synchronization of data. Process synchronization refers to the idea that multiple processes are to join up or handshake at a certain point, so as to reach an agreement or...
.
Object Request Broker
With Object Request BrokerObject request broker
In distributed computing, an object request broker is a piece of middleware software that allows programmers to make program calls from one computer to another via a network...
middleware, it is possible for applications to send objects and request services in an object-oriented system.