CHAPTER 5 ENTERPRISE ARCHITECTURES

CHAPTER 5 ENTERPRISE ARCHITECTURES
1. What is information architecture and what is information infrastructure and how do they differ and how do they relate to each other?

Information architecture (IA) is the art of expressing a model or concept of information used in activities that require explicit details of complex systems. Among these activities are library systems, Content Management Systems, web development, user interactions, database development, programming, technical writing, enterprise architecture, and critical system software design. Information architecture has somewhat different meanings in these different branches of IS or IT architecture. Most definitions have common qualities: a structural design of shared environments, methods of organizing and labeling websites, intranets, and online communities, and ways of bringing the principles of design and architecture to the digital landscape. The term information architecture describes a specialized skill set which relates to the interpretation of information and expression of distinctions between signs and systems of signs.
In the context of information systems design, information architecture refers to the analysis and design of the data stored by information systems, concentrating on entities, their attributes, and their interrelationships. It refers to the modeling of data for an individual database and to the corporate data models an enterprise uses to coordinate the definition of data in several (perhaps scores or hundreds) of distinct databases. The "canonical data model" is applied to integration technologies as a definition for specific data passed between the systems of an enterprise. At a higher level of abstraction it may also refer to the definition of data stores.
An information infrastructure is defined by (Hanseth, 2002) as "a shared, evolving, open, standardized, and heterogeneous installed base" and by (Pironti, 2006) as all of the people, processes, procedures, tools, facilities, and technology which supports the creation, use, transport, storage, and destruction of information. Infrastructure architecture - includes the hardware, software, and telecommunications equipment that, when combined, provides the underlying foundation to support the organisation’s goals – this must be dynamic as it will change as the organisation changes.









2. Describe how an organisation can implement solid information architecture?
Information architecture has become synonymous with information architecture for the web. However, as more organizations are adopting content management systems to manage both web and enterprise content, there is a new area of information architecture emerging—the information architecture of content management. One of the key factors for a successful content management implementation is a solid information architecture. Too often organizations implement content management without identifying the authors' needs, without looking closely at the content to determine how it could be most effectively structured to support user/customer needs, and without analyzing their current and desired content life cycle. This results in resistance to adoption, increased costs, and failure to achieve the desired results. Information architecture can make a significant contribution to the success of your content management solution.

The components of information architecture:

There are a number of components of information architecture that are key in building a solid base for a content management implementation. They include analysis, content models, granularity, metadata, reuse and repository architectures, reuse management, and content management.
Analysis
Good information architecture requires that you start with a thorough analysis of your organizations' needs, your current and desired content life cycle, your customers' needs, the state of your current content, and your technological requirements. During the analysis phase, you need to look at your content very closely to determine how it's put together and the types of content it contains. This will help you to determine opportunities for reuse. You also need to talk to the people who create and use the content to learn what their issues are. This will help you to determine problem areas in work processes that can be addressed in workflow.
Content models
One of the most critical phases of your information architecture is building the content models on which your content management strategy is based. Content modeling involves identifying and documenting the structure of your content in detail. During the content modeling phase, you determine the elements required for each information product (or output) and how each information product will be designed for optimum usability and reuse. Content models define the structure and organization of your information products, indicating which individual elements they contain, their frequency, and their usage (e.g., is an element optional or mandatory). Models become the road map for your content and are used to develop DTDs/schemas (if you are using XML), or content frameworks and templates.
Granularity of content
Designing the granularity of your content can sometimes be problematic. Authors typically like content very granular so they know exactly what to put into an element (e.g., overview, procedure step). Very granular content usually results from more semantic models (models with tags that indicate the meaning of the element such as “overview” instead of tags with generic names such as “body” or “para”). Highly semantic models are more problematic for style sheet designers because all unique elements require an individual style. Because semantic names by their nature are unique, all semantically-named elements require their own styles.
Granularity also affects how you reuse content. Content that is too granular can be difficult to manage in your content management system, but content that is not granular enough may not be as reusable. Accordingly, CMS developers may push back on the level of granularity, opting for content that is not granular. Analysis of reusability, authoring processes, and tools is important when determining granularity and as you develop your information architecture, you will make changes to your granularity as you determine the optimum level of granularity for everyone.
Metadata
There are typically two types of metadata: categorization metadata and element metadata. Users tend to retrieve information based on categorization metadata, whereas authors tend to retrieve information based on element metadata. Categorization metadata is used extensively on web sites to categorize content for effective retrieval. It is also used extensively in document management to classify documents for storage. Authors, on the other hand, use element metadata to classify elements of content for reuse, retrieval, and tracking. Care should be taken to ensure that you can retrieve your elements once stored. Your ability to reuse information is only as good as your ability to find it. And if you employ systematic reuse (see Reuse architecture) your metadata must be very thorough so that the system can correctly find and populate the content into the required information products and into the required places within information products. Like granularity, metadata design also continues to develop as you refine your architecture.
Reuse architecture
Content can be reused within an information product, across information products, and potentially across the enterprise. Traditionally, the most common form of reuse has been opportunistic, meaning that authors make a decision whether to reuse content or not. However, opportunistic reuse is also the least efficient because it requires that authors know a reusable element exists and what it is called, then find the element and reuse it in their information product. In addition, if authors are not aware that an element already exists, they may recreate it causing multiple elements to proliferate in your content management system. This also makes it difficult to know which of the multiple elements is the definitive one.
Alternatively, systematic reuse is automatic reuse. Once specific content has been identified as reusable in a specific location, it is automatically inserted (auto-populated) into the appropriate locations. Authors do not have to determine if the reusable content exists or search for, retrieve it, and insert it into the appropriate places. Systematic reuse ensures that content is automatically reused where necessary, thus reducing the burden on authors. When designing your reuse architecture, considerable analysis of information products is required to decide which elements are systematically reusable and where.
Once you've decided which elements are systematically reusable, you create content and structure reuse maps as part of your reuse architecture. The content reuse maps identify where content can and should be reused and if it should be reused identically or can be used derivatively (with change). Content reuse maps are used by your content management system to programmatically (automatically) ensure that content is reused. In addition to identifying content reuse, you need to identify structural reuse as part of your reuse architecture. Structural reuse identifies where common structures are reused. For example, you might have a product description element in a brochure, but you would also have a product description element on the web. Even though those product description elements may be structurally the same, they may contain different content. Structure reuse maps are used by DTD/template developers in creating consistent structures for authors to follow.
Repository architecture
The repository architecture defines how you will structure your repository. For example you may have “building block” directories that include content that is frequently reused (e.g., glossary, procedures, product descriptions) and the remainder of your content stored in information product directories (e.g., all brochures) that are further organized by product. Or you may decide to organize your content by product with each of the information products as a subset of the product. You need to determine what is the most effective repository structure for your needs. Note, however, that the identified structure is not a physical file structure. Content is stored in the database, not in directories. The repository structure enables your authors to easily find information.
Reuse management
An area of information architecture that is frequently overlooked is that of reuse management. If authors opportunistically reuse content and create derivatives of the content, it quickly becomes difficult to identify which element is the definitive one. Your content management system will end up looking like your current file structure and you will have no clear idea of what is source content, where content is reused, and if there are multiple versions of the same piece of content. Reuse management means creating rules to manage your reusable content. The reuse rules are formalized in your content management system through workflow and in your system configuration.
Content control
Content control, as part of your information architecture, identifies how your content should be managed. You need to determine how content should be controlled through its life cycle and what security should be applied to it. Content control is tightly integrated with your reuse management strategy and business practices and like reuse management, it is formalized in workflow.
http://www.rockley.com/TheRockleyReport/V1I1/Information%20Architecture.htm

3. List and describe the five requirement characteristics of infrastructure architecture?

The five requirement characteristics of infrastructure architecture are:-
•Reliability- High Accuracy and low Accuracy puts the organisation at risk.
•Scalability- Systems ability to meet growth requirements and involves Capacity planning
•Flexibility- Able to meet changing business demands andthis might involve multinational challenges.
•Availability- High availability 99.999% uptime and ensures business continuity
•Performance- How quickly a system performs a certain task and growing pressure on systems to be faster




4. Describe the business value in deploying service oriented architecture?
•Service oriented architecture (SOA) is a business-driven IT architectural approach that supports integrating a business as linked, repeatable tasks or services
•SOA ensures IT systems can adapt quickly, easily, and economically to support rapidly changing business needs
•Using meta data and existing applications, users can re-use applications (services) many times for different tasks, making development cheaper and more flexible.
•A SOA allows enterprises to plug in new services or upgrade existing services in a granular fashion.
•Respond more quickly and cost-effectively to changing market-conditions
•The key technical concepts of SOA are:
a.services
b.interoperability
c.loose coupling
•Service oriented architecture begins with a service
•(SOA) service - can be a business task, such as checking a potential customer's credit rating only opening a new account
•Services are “like” software products
•A Web service provides one way of implementing the automated aspects of a given business or technical service.







5. What is an event?
Event – is an electronic message indicating that something has happened, it detect threats and opportunities and alerts those who can act on the information.

6. What is a service?
Service – contains a set of related commands that can be re-used, it is more like a software product than they are a coding project
• Need to be reusable if they are going to have an impact on productivity.

7. What emerging technologies can companies use to increase performance and utilise their infrastructure more effectively?
• Grid computing
• Virtualisation
• Service oriented architecture (SOA)
• VoiP
• Lan (Local Area Network)
• Wan (Wide Area Network)
• Man (Metropolitan Area Network)
• VPN (Virtual private network)
• VAN (Value-added network)
• Wireless local area network (wLAN)
• Cellular phones and pagers
• Cordless phone peripherals
• Satellite television
• Wi MAX wireless broadband
• Security sensor