¶ … Object Oriented Hypermedia design model and the four-step process involved in the development of the model. This section will provide an explanation for each step in the process. Then we will discuss the past, present and future business uses of the model. This will explore the importance of the model in business applications that are conducted through the Internet. We will also provide details about the compatibility of the model and compare the model to similar applications such as HDM and OOHM. Finally, we will discuss the strengths and weaknesses of the model. Including that navigational design of the model and the costly overhead and training involved in implementing the application. There will be several types of sources used during the course of this discussion. Most of these sources will be essays and articles written by Rossi and Schwabe who invented the Object Oriented Hypermedia Design Method. In addition there will be a myriad of article written by computer programming specialists and researchers.

Brief overview of the Object Oriented Hypermedia Design Model

The Object Oriented Hypermedia Design Model uses "abstraction and composition devices in an object oriented framework to allow a concise description of complex information items, and on the other hand, allow the specification of complex navigation patterns and interface transformations." (Rossi and Schwabe 1998) OOHDM is developed through a four step process which includes; conceptual design, navigational design, abstract interference design and implementation. (Rossi et al.)

Conceptual Design Phase

During the conceptual design phase the model of the application domain is created using object oriented modeling principles. The creation of the application domain determines the discourse of the application. There are two types of objects that are represented in this phase: the objects that provide computational support and the objects that will be perceived as nodes in the navigational design phase. (Rossi et al.)

The navigational design phase is very important to the success of any hypermedia application because navigation is what separates hypermedia design from other applications. Navigation allows users to navigate a space created of objects. During this phase transformations are specified which determine how navigation will operate

The third phase is the abstract interface design phase specifies interface objects that are responsible for mediating user interaction with navigation objects. The interface model specifies which interface objects the user will perceive; which interface objects will activate navigation; how multimedia interface objects will be synchronized; and the interface transformations that will take place. (Rossi et al.)

During the final phase of implementation the mapping is created for the objects in the conceptual, navigational and abstract interface phases. All of the proceeding phases are done independently of the implementation platform. (Rossi et al.)

Past Present and Future Business Uses

Past Uses

Theodor Holm Nelson created the Hypermedia Design Model in the mid-60's. He hoped to create a system by which the reading of different documents was not subject to sequence. (Hypermedia 2001, ¶1) In the past the Hypermedia model was used to simply create web-based applications. The primary use of Hypermedia was to reduce file transfer times and compile information into a format that would be accessible to people over the World Wide Web. Hypermedia also helped to create networks and early navigation systems for businesses.

The OOHDM model was created to simplify the hypermedia model and to address some of the problems presented by the model. OOHDM did this by creating a navigational system and navigational patterns that allow businesses to provide customers with valuable content over the Internet.

Present Uses

The current uses of OOHDM involve creating e-commerce solutions. E-commerce is fast becoming popular as a way of delivering of business processes and applications over the Internet. An increasing number of organizations require the performance of web-based solutions with functionality to complete commercial transactions over the World Wide Web. These transactions include the acceptance of credit cards so that customers can make purchases over the net and the ability to provide customers will valuable content information about the business. (Abrahao, Fons, Pastor 2000, ¶ 2)

A well-designed application is important because business owners understand that how a website functions will either create repeat customers or discourage customers from visiting the site. It is essential that a website is easy to navigate and that it functions in an efficient manner. It is also important for a business to be able to correct problems with the system quickly, which will prevent the loss of customers and profits. As a result of the demands that are placed on business to have an efficient website a precise software production process...

(Abrahao, Fons, Pastor 2000, ¶ 2) The OOHDM process provides the stability needed to accommodate an e-commerce site.
OOHDM is also used to improve the functions of Web information systems through the use of design patterns, which make websites easier to navigate. OOHDM is used in this area because it provides for a clear separation of conceptual, navigational and interface designs. These distinctions are imperative because it allows programmers to concentrate on the hypermedia metaphor of Web Information Systems. (Rossi, Schwabe, Lyardet 1999, ¶ 3)

Future Uses

OOHDM will continue to be used to aid business with e-commerce solutions and structuring Web Information Systems. It is evident that the method will continue to grow and more research will be done to make the method even more efficient. This efficiency would make the system less expensive to maintain and make Web Pages even easier to navigate. In addition there will inevitably be new applications that are discovered and used instead of OOHDM.

Compatibility

User's hardware requirements for text- and graphics-based hypermedia is very modest, and most new PCs and Macs have sufficient speed to play video clips. Conversely there is a problem that is created when the model is used on a network. This is because the application is extremely complex and needs large amounts of bandwidth to operate properly. The fact that the infrastructure of bandwidth solutions is improving on a consistent basis does no negate the fact that application can outstrip the network bandwidth. (Tissue, ¶ 4)

Experts believe that bandwidth constraints will most likely continue for many years. In addition the limitations are used to place sensible restrictions on the nature of the material that can be successfully dispersed over the World Wide Web. It is important to remember that bandwidth considerations also include the end users network connections, which may produce a variety of file-transfer speeds. (Tissue, ¶ 4) The OOHDM application itself can be implemented on most hypermedia-supported platform. (Ashman, Bieber, Kukkonen 1999, ¶ 7)

Comparisons

The following comparison of OOHDM with other approaches such as HDM, ADM, OOHM, OOWS and OOH is based on conceptual design and navigational design and interface design. The purpose of this comparison is to clearly explain the differences that the Object Oriented Design Method has with these other applications. This comparison is taken from the article "Building E-Commerce Applications from Object-Oriented Conceptual Models"

During the conceptual design phase, the Hypermedia Design Model approach is based on E-R diagrams and does not utilize the Object Oriented model. The Araneus Design Model (ADM) is not based on a conceptual model and depends on the navigational model. The Object Oriented Hypermedia Design Model uses an Object Oriented conceptual model based on modifications of the Unified Modeling Language these modifications do not permit the objects of the application to offer services to the end user. The OOWS and OOH-Method use the Object Oriented Method as a conceptual model. (Abrahao, Fons, Pastor 2000,)

In the navigational design phase, all of these applications introduce node and link concepts as the fundamental structures for the explanation of hypermedia systems. Conversely, the explanation is considered by the approaches in different ways. These approaches to the explanations can be separated into two categories. The Hypermedia Design Model and the Araneus Design model represent the first category. The second category includes the OOWS, OOHDM and OOH-Methods. (Abrahao et al.)

The first category does not make any distinction between the conceptual and navigational models, but instead they represent navigational characteristics in a conceptual model based on E-R design. On the other hand the second category distinguishes between an Object Oriented conceptual model and a navigational model, which regulates the observation of each user of the information system. (Abrahao et al.)

Within the second group, there is also a difference in the navigational unit in OOWS and OOHDM (navigational context and node, respectively), which is an element, made up of several groups from the conceptual model. While, in OOH-Method, the navigational unit is a class from the conceptual model (navigational class). Additionally, a building block (navigational target) is used to group classes. This building block does not imply that there be any necessary navigation; it is simply used for the organizational purposes of the method. This notion is also defined in Object Oriented Hypermedia Design Model application as navigational context. (Abrahao et al.)

The final aspect of navigational design involves the dynamic behavior of the various models. Neither Hypermedia Design Model nor Object Oriented Hypermedia Design Model makes any declaration about the likelihood of including services in their systems. The only dynamic behaviors that these methods…