Home > Articles > Software Development & Management > Architecture and Design

📄 Contents

  1. Some Background
  2. The What
  3. The Why
  4. Architecture Views and Viewpoints
  5. Summary
  6. References
This chapter is from the book

Architecture Views and Viewpoints

Books, articles, research, and related publications on the different views of software architecture have been published. There are different schools of thought that prefer one architecture viewpoint over the other and, hence, practice and promote its adoption. In the spirit of this book’s theme, I do not devote a separate chapter to an exhaustive treatment of the different views of software architecture; rather, I present one that I have found to be practical and natural to follow and hence to use.

IBM (n.d.) defined a set of viewpoints called the IBM IT System Viewpoint Library. I have found it to be quite complete, with appropriate coverage of the various facets of a system’s architecture. The library consists of four basic viewpoints and six cross-cutting viewpoints. Figure 2.3 provides a pictorial representation.

Figure 2.3

Figure 2.3 Viewpoints in the IBM IT System Viewpoint Library (see “References”).

The four basic viewpoints of the IBM IT System Viewpoint Library are the following:

  • Requirements—Models elements that capture all the requirements placed on the system, including business, technical, functional, and nonfunctional requirements. Use cases and use case models are the most common means of capturing the requirements viewpoint.
  • Solution—Models elements that define the solution satisfying the requirements and constraints; further organized into two categories:

    • Functional—Focuses on the model elements that are structural in nature and with which the system is built by not only implementing the elements but also wiring the relationships between the elements (both static and dynamic). The functional architecture (the focus of Chapter 7, “The Functional Model”), broadly speaking, is the construct through which the details of this viewpoint are captured.
    • Operational—Focuses on how the target system is built from the structural elements and how the functional view is deployed onto the IT environment (which consists of the network, hardware, compute power, servers, and so on). The operational model (the focus of Chapter 8, “The Operational Model”) is the most common architecture construct through which the details of this viewpoint are captured.
  • Validation—Models elements that focus on assessing the ability of the system to deliver the intended functionality with the expected quality of service. Functional and nonfunctional test cases are often used as the validation criteria to attest to the system’s expected capabilities.

As shown in Figure 2.3, the four basic viewpoints are interrelated. The functional and operational viewpoints collectively realize (that is, implement and support) the requirements viewpoint; both the functional and operational viewpoints are validated for acceptance through the validation viewpoint. Note that the “solution” construct does not appear explicitly in Figure 2.3; for the sake of clarity, I have only shown the functional and operation constructs that collectively define the solution construct.

The library also contains six cross-cutting viewpoints, depicted in Figure 2.3 as concentric squares around the four basic viewpoints. The idea is to illustrate the point that the cross-cutting viewpoints influence one or more of the basic viewpoints.

The six cross-cutting viewpoints are as follows:

  • Application—Focuses on meeting the system’s stated business requirements. The application architect plays the primary role in addressing this viewpoint.
  • Technical—Focuses on the hardware, software, middleware (see Chapter 5, “The Architecture Overview,” for a definition), and packaged applications that collectively realize the application functionality and enable the application to run. The infrastructure and integration architects play the primary roles in addressing this viewpoint.
  • Systems Management—Focuses on post-deployment management, maintenance, and operations of the system. The application maintenance and management teams play the primary roles in addressing this viewpoint.
  • Availability—Focuses on addressing how the system will be made and kept available (for example, 99.5 percent uptime) per the agreed-upon service-level agreements. The infrastructure architect plays the primary role in addressing this viewpoint, with support from the application and the middleware architects.
  • Performance—Focuses on addressing the performance of the system (for example, 400 milliseconds average latency between user request and the system response) per the agreed-upon service-level agreements. The application architect plays the primary role in addressing this viewpoint, with support from the middleware and infrastructure architects.
  • Security—Focuses on addressing the security requirements of the system (for example, single sign-on, security of data transfer protocol, intrusion avoidance, among others). Some of the security requirements—for example, single sign-on—are addressed primarily by the application architect role, whereas other requirements such as data protocols (HTTPS, secure sockets) and intrusion avoidance are addressed primarily by the infrastructure architects.

There are many more details behind each of the basic and cross-cutting viewpoints. Each viewpoint has a set of elements that collectively characterize and define their responsibilities. Understanding them can provide key insights into how each viewpoint may be realized. Although there are many details behind each of the basic and cross-cutting viewpoints, the idea here is to acknowledge their existence and realize the fact that any system’s overall architecture has to typically address most, if not all, of the viewpoints. Awareness is key!

After having personally studied a handful of viewpoint frameworks, I feel that most, if not all, of them have a degree of commonality in their fundamental form. The reason is that each of the frameworks sets about to accomplish the same task of establishing a set of complementary perspectives from which the software architecture may be viewed, with the goal of covering the various facets of the architecture.

The choice of adopting a viewpoint framework, at least from the ones that are also quite established, hardened, and enduring, depends on your level of belief that it addresses your needs and your degree of comfort in its usability and adoption.

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020