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  • Business Object Design and Implementation
    time we did not think of database designs as being database objects in hindsight they were There were databases for EMPLOYEEs PROJECTs TEACHERs COURSEs STUDENTs FACILITIES FINANCEs etc Each database was founded on a well known coherent business concept As each object that is the employee project teacher course and student moved through well known states certain data structures were valued modified and or deleted To accomplish these state transformations whole information systems were created These information systems either employed their own database transformation logic or used the DBMS self contained database processes to accomplish the state transformations Independent Logical File DBMS A third set of DBMSs also arose by the late 1960s These DBMSs were all about making traditional file access easier through the standard 3GL Adabas from Germany certainly exemplified these systems If you have files then after a quick and easy data loading operation you have a database The common expression was Database in a Day These DBMSs typified by Adabas Model 204 Focus RAMIS Nomad and Inquire allow several levels of data structure nesting the operations of select project divide join etc RAMIS FOCUS and Nomad have a full complement of Joins and Unions These systems I call Independent Logical File systems ILF all existed and were running production databases before 1970 These ILF systems were characterized by shallow data structures and index based or sequential l file access through 3GLs These DBMSs however did not completely model business data objects as completely as the other two DBMS classes did Relational DBMS By the time relational was discovered in 1970 every viable DBMS concept was already in some production class DBMS of one type or another What relational did however was to cause two very valuable concepts activities database design and business policy based database objects to be forgotten During the 1970s and through the end of the 1980s databases just plain grew The awards seemed to go to the one who could build the largest most number of tables and rows database who could push through the most number of rows transactions in a second who could have the most number of columns in a table and the like All the while the concept of business policy analysis coherent database design etc fell by the wayside All this is understandable as we ve always believed technology to be the source of all answers X3H2 X3H2 was charted in 1978 to standardize the CODASYL network data model The DDL work was completed two years later The subschema copied from COBOL s subschema language and the DML work a complete new invention compliments of Len Gallagher was completed by 1983 The standard Network Data Language was delayed a year so that the SQL standard started as the Relational Data Language RDL could catch up Both became standards in 1986 The NDL is characterized by flat records with contained vectors and groups that are able to form structures through single and multiple member sets a subschema language and

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  • Business Object Design and Implementation
    October 1995 Austin TX Abstract After an evaluation of the Common Object Request Broker Architecture CORBA we plan to introduce a CORBA based 3 tier architecture for the development of different systems The evaluation has been carried out in order to verify the this architecture in a large scale financial environment including legacy systems Facing this challenge we implemented several client and server applications based on different legacy systems The server applications run on UNIX machines access other UNIX CTOS and MVS machines allowing access from UNIX and Windows 3 1 as well as Windows NT They are based on IMS and DB2 transactions different interfaces to these transaction systems Sybase Open Servers a document generator and an interface to an electronic document management system We believe that this approach can beneficially be used today in large scale systems In our case one of the main benefits is that CORBA can help to solve current problems integration of legacy systems use of heterogeneous development tools etc as well as future problems migration to an open systems architecture allowing to use new and legacy systems at the same time The 3 tier approach we plan to introduce in different projects consists

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  • The Architecture Reference Model
    As depicted above each category is a grouping of relevant components In the Reference Model only the types of components are shown while in the actual Business Architecture specific components would be identified For example the Business Process category might include processes for selling a product while the Business Component category may contain an Address Component The question then arises how does one identify the proper set of components The answer varies according the to category For the Technical Infrastructure Category we can look to industry and standards organizations for support For example IBM s Open Blueprint OMG s CORBA and Microsoft s COM OLE When we move up to the Business Components category we find no standards but we do see work going on in OMG Therefore key to the success of the Reference Model will be its ability to incorporate new standards as they emerge so as to identify a proper set of components Components are however only one aspect of an architecture The dynamics of the architecture must also be captured the way components are configured together to solve a problem To that end we incorporate patterns and frameworks and like components they exist in each of the categories of the reference model These provide standard designs configurations to specific problems Frequently there may be several alternatives each offering a different trade off on performance and cost By cataloguing this information with the architecture developers have a mechanism to go back to their business partner and explain the issues they face the trade off available thus including the partner in the decision making process If we look at each category we can see that each one implies a different skill the Business Strategy requires those with strong business and strategic skill the Business Process category requires those

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  • Business Object Design and Implementation
    nations The notion of a legally recognized enterprise is important because it is associated with security and authentication mechanisms that are required to be able to fully specify security semantics for the ObjectCosmos We utilize the notation Cover to represent a cover in a textual description For example Figure 1 depicts the Composition cover over the ObjectUniverse The notation is suggestive of hierarchical nesting of covers The notation is capable of unambigously identifying a specific cover as in for example Composition BNR Ottawa which identifies the composition cover identifying the BNR Ottawa objects A separate cover over the ObjectCosmos which is orthogonal to Composition is Class Class consists of meta information specifying the class or type information for the ObjectUniverse We note that OMG s IDL MODULE construct is capable of specifying Class over the ObjectCosmos 2 2 Being We refer to Composition and Class as Being ie it specifies completely the existential semantics for the ObjectUniverse These existential semantics are in a sense analogous to the notion of objects and their distribution in space in the real cosmos 2 3 Doing Each sparc operative as a causal agent in the ObjectCosmos is coupled to a Doing meta object that describes its current state and sphere of influence in the ObjectCosmos A Doing cover effectively describes sparcs and their operations on objects within the lifetime of each sparc Doing effectively completely specifies the operational semantics for the ObjectUniverse These are in a sense analogous to the notion of causal change agents and their effects in time in the real cosmos Sparcs are ultimately traceable to persons having legal authority within an Enterprise cover Sparcs are also primitives used to specify Consistency and Security semantics further described below 2 4 Consistency Consistency deals with consistency semantics in the ObjectCosmos under conditions of sparcs with intersecting colliding Doing meta objects 2 5 Security Security semantics specify the security semantics operative in the ObjectCosmos by specifying the keys held by sparcs that permit them to open the appropriate locks covering the objects they wish to access 3 Object Schema The framework deals with multiple schema analogous to the ANSI SPARC 3 schema model for data These schema are a CosmicSchema an ImplementationSchema and a ViewSchema These correspond approximately to the ANSI SPARC conceptual schema internal schema and external sub schema 3 1 CosmicSchema The CosmicSchema is a description of the ObjectCosmos in terms of its orthogonal covers of Being Doing Consistency and Security Figure 1 above is a CosmicSchema representing the Composition sub cover of Being It deals with conceptual notions rather than implementation notions 3 2 ImplementationSchema Figure 2 depicts the ImplementationSchema It is a separate independent layer on top of which resides the CosmicSchema represented by Figure 1 The CosmicSchema is mapped into the ImplementationSchema by the various implementations of portions of the ObjectCosmos AE AE M m DE DE m M m DE DE m AE AE Figure 1 Internal Schema Platform At the InternalSchema there are a number of

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  • Business Object Design and Implementation
    in the Financial Data Warehouse Project of IBM Japan In its uncompromised or epistemologically adequate form an REA model views the enterprise as a series of value added processes each of which contains at the abstraction level deemed appropriate for a particular enterprise a stereotypical object constellation with eight entities and seven relationships We estimate that an accountability infrastructure built in object oriented form by repeated use of this process model could account for well over half of the data definitions needed in a typical corporate enterprise Some of the open workshop questions that have REA implications are these 1 Specification of business objects We use microeconomic primitives starting with the definition of an economic resource something which is scarce has economic utility and is under the control of the enterprise 2 Do we need large grained object design patterns We answer in the affirmative and offer a full process model of economic phenomena that equates to a Porter type value chain 3 How do we identify a business object As instances of the general classes of economic phenomena such as economic resources economic events economic agents stock flow relationships control relationships and duality relationships 4 How do business objects interface with legacy systems We have developed a methodology for judging the semantic expressiveness of a given set of legacy implementations in other words how much compromising went on during its analysis and design These measures show where the uncompromised object oriented structures and accounting file systems for instance could possibly be coupled 5 Where do we put business rules and control structures We propose using existing accounting concepts of internal control specified semantically and integrating them with the REA accountability infrastructure that is the enterprise object architecture We suspect that many of the semantic business frameworks that other workshop

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  • Business Object Design and Implementation
    communicate Classes The templates for defining types of objects The strength of the object oriented approach lies in encapsulation and enabling reuse This reuse promotes the evolution of systems over time as compared to redeveloping systems from scratch thus reducing the impact of ongoing maintenance Object Oriented Early Experiences Confusion in the area of object oriented techniques was introduced when object oriented was confused with GUI interfaces client server marketing departments who arbitrarily called their products object oriented and programming languages Traditional languages and databases allowed object oriented techniques to be applied however the majority of systems development efforts reverted to structured techniques at some point Object oriented languages have evolved to support class and object use Some of the early languages had difficulty navigating traditional relational database management systems Several methodologies have evolved to support development within the object oriented framework Current Trends in Object Oriented The initial difficulties with data access experienced by object oriented applications have been overcome with more advanced interfaces as well as the advent of object database management systems Of the major accepted methodologies a convergence is apparent with respect to the impact of concerted analysis and design Requirements Although current client server technology is sufficient for small projects it fails to meet today s need for the same abilities on a large scale Any future development must be able to meet the demands for flexibility and complexity and still accommodate both application and technological requirements The following table describes the requirements for future development Requirement Support distributed transaction management Purpose To maintain data and transaction integrity Description A system must prevent the data in a database from ever being corrupted even when different parts of complex transactions run on different servers A system must be able to access more than one server process and select the most appropriate server process for each transaction or part of a transaction Requirement Support distributed systems management Purpose To administrate the components of a distributed enterprise Description A system must enable the configuration monitoring and management of distributed systems components These components include the networks servers gateways and database servers Requirement Utilize standard open interfaces Purpose To allow the use of flexible platform components Description A system must allow the utilization of specialized components in a heterogeneous environment To enable this to take place on a continuous basis the system must adhere to known standard open interfaces Requirement Allow processes to access static data locally Purpose To use communications networks more efficiently by reducing the number of messages for each request Description A process must be able to access the static data it needs to formulate or complete a request with minimal network traffic Requirement Manage development complexity Purpose To accommodate increasing application complexity Description A system must enable the use of object oriented techniques which minimize application re engineering during the evolution of more complex systems Requirement Support and enforce business rules Purpose To speed up processing of requests and to consistently enforce business standards Description

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  • Business Object Design and Implementation
    not as obvious we can cite the mapping between SNMP and OSI SM where different models of network management do exist Although using the SNMP model in an OSI environment is not difficult the solution has to be nonetheless creative NMForum 4 0 The components of a model and an example Providing an information model is ultimately providing successive level of semantics with at the core a common understanding of the goals of a system Some of the components of an information model are well known and require little expansion The initial components of identification of purpose through to the analysis of requirements and the final component of building the hardware and software solution have been well explored The intermediate components of conceptual design and stylistic design have been less well explored In the following we will examine the components of an information model which includes provisions for semantic description We will illustrate the different components of the model by drawing an analogy between building architectures and telecommunication architectures 4 1 Purpose Building A church to meet the requirement of communal worship Telecommunications AManagement System to meet the requirement of remotely managing distributed systems In any development process the first step is requirements analysis As mentioned requirements analysis is well understood Jacobson Brooks The importance of this phase of development to our current argument is in insuring that the rest of the information model meets these requirements 4 2 Conceptual Design Building An arch provides support allowing the creation of open space within a building Telecommunications a notification is an event report originating from a managed object reporting its status to a managing object An architectural concept identifies a particular mechanism required to meet one or more requirements Its semantics must be well defined The identification of architectural concepts does not necessarily preclude any implementation technology it should be technology independent It does however provide a point to which different implementation can trace common semantics We know that an arch will provide support to an overhanging structure Conceptually it is irrelevant if the arch is round lancet or basket handle Similarly we know that a notification will carry information from a managed object to a managing object The exact manner in which this interaction is begun and carried out does not enter into consideration in this component of the model 4 3 Stylistic Design Building Gothic a recognizable architectural style with provides a certain form and function Telecommunications alarm notifications by event forwarding Style is an important step in model refinement It is akin to design patterns Gamma JOOP with the exception that the semantics are an integral part of the style Design patterns are normally devoid of semantics to enhance reusability Choice in building style may affect effectiveness width and weight ratios in the case of our Gothic arch similarly the choice of software style notifications by event forwarding versus notifications by polling also affect the effectiveness of the solution For example in large networks alarm notification by polling

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  • Business Object Design and Implementation
    operations and life cycle states are relevant for an actor in the context of a certain business process In this two tiered manner information objects are integrated with the workflow model 2 Business processes define the chains of organizational activity threading through different business units A process is defined in terms of a sequence of process steps each of which may again be a process at a lower level A process step requires a set of resources actors objects and has a duration a value addition and satisfies an organizational goal The trigger for a process to happen is the occurrence of an event An event may either be a state change of an object a condition becoming true a time event or an external event e g a phone call from a customer However the occurrence of an event in itself may not be enough to trigger a process The precondition rule for the step must also be satisfied Apart from pre and postconditions rules may be state rules or integrity rules In order to support enhanced animation and simulation of business models it is important that the meta model defined has an operational basis This requires an event based model where triggers and rules are defined as the precise conditions governing process execution Furthermore instances of objects and actors must form an integral part of the model In order to aid the definition of an interpreter for business models it is beneficial to map the meta model to an underlying formal representation e g state transition systems or Petri nets 4 5 Although OO methods in general pay little attention to business modelling as such e g 6 the methods of Odell 4 and recently Jacobson 3 cover at least part of this domain We are investigating the possibility of mapping the underlying meta models of these approaches or at least a major part of them to our own model If successful this would enable CASE tools to display alternative notations based on the user s method preference Tool Requirements In essence an integrated object toolset poses requirements far beyond paper based methodologies The true problem is one of integrating many different partially overlapping views in a flexible manner Therefore a set of integrated model based development tools can only be constructed effectively on the basis of an underlying active repository This repository provides the data integration and consistency of the meta model supported by the tools In addition it must notify tools of relevant changes caused by some other tool through an event mechanism Furthermore extensibility e g for mapping existing methods requires an open repository environment The primary goals of an Object Business Modelling toolset must be to make modelling easier to understand for domain experts and end users and furthermore to aid them in the transition to application design As discussed a meta model geared towards their communication requirements is essential It also requires that the model information is presented in a graphical fashion by

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