Non Functional Requirements Component Type Applicability

Non Functional Requirements (NFR) define the constraints or the way Functional Requirements are implemented. NFRs are categorized as different types of constraints.  Those categories are great for the enterprise but don't really help determine which NFRs apply in any given Business Feature. One way to remedy this is to create a second type of categorization that identifies which NFRs apply for a given component type, The individual NFRs in a category may only apply to certain deployable types.

Related

Video: https://youtu.be/S4MKvpNNcNo
Blog (Related): https://joe.blog.freemansoft.com/2022/06/non-functional-requirements-nfrs-in.html

Classic NFR Categorization

NFRs are generally grouped with related constraints.  You can find a variety of categorization taxonomies with a quick internet search.  From Wikipedia:

Non-functional requirements are often mistakenly called the "quality attributes" of a system. There is a distinction between the two. Non-functional requirements are the criteria for evaluating how a software system should perform and a software system must have certain quality attributes in order to meet non-functional requirements. 
  1. Execution qualities, such as safety, security, and usability, are observable during operation (at run time).
  2. Evolution qualities, such as testability, maintainability, extensibility, and scalability, are embodied in the static structure of the system.
https://en.wikipedia.org/wiki/Non-functional_requirement

Example: A team may have a set of security NFRs and a set of governance NFRs.  
  • Encryption at rest, encryption in flight and authenticated endpoints are all security NFRs. 
  • Functional Test Coverage and Automated Deployments might all be categorized as Maintainability NFRs.

Component Type Applicability

The standard NFR categories provide a way of grouping related NFRs by type.  They don't provide any simple guide to determining which NFRs apply for any specific Feature.  This means we need to scan the entire list of NFRs whenever we refine a business feature.  We can simplify this by providing a guide as to which NFRs apply in various situations.  We can create a second categorization that groups disparate NFRs by software and control type applicability.  Individual NFRs can be applied to multiple component types or control types. 

Component / Business Feature Applicability

Business Features, in the backlog, typically will be implemented using one or a few technical components and thus component types.  We know the likely constructs at the time of Feature Refinement.  This means we can simplify our NFR Acceptance Criteria in a feature by listing the Component Categories rather than all of the individual applicable NFRs.  We can at least use these Component Categories as the first cut of applicability.


Video

Created 2022 09

Comments

Post a Comment

Popular posts from this blog

Installing the RNDIS driver on Windows 11 to use USB Raspberry Pi as network attached

Image
I do a lot of my development and configuration via ssh into my Raspberry Pi Zero over the RNDIS connection. Some models of the Raspberry PIs can be configured with  gadget drivers  that let the Raspberry pi emulate different devices when plugged into computers via USB. My favorite gadget  is the network profile that makes a Raspberry Pi look like an RNDIS-attached network device.  All types of network services travel over an RNDIS device without knowing it is a USB hardware connection. A Raspberry Pi shows up as a Remote NDIS (RNDIS) device when you plug the Pi into a PC or Mac via a USB cable. The gadget  in the Windows Device Manager picture shows this RNDIS Gadget connectivity between a Windows machine and a Raspberry Pi. The Problem Windows 11 and Windows 10 no longer auto-installs the RNDIS driver that makes magic happen. Windows recognizes that the Raspberry Pi is some type of generic USB COM device. Manually running W indows Update  or  Upd...
Read more

Understanding your WSL2 RAM and swap - Changing the default 50%-25%

Image
The Windows Subsystem for Linux operates as a virtual machine that can dynamically grow the amount of RAM to a maximum set at startup time.  Microsoft sets a default maximum RAM available to 50% of the physical memory and a swap-space that is 1/4 of the maximum WSL RAM.  You can scale those numbers up or down to allocate more or less RAM to the Linux instance. The first drawing shows the default WSL memory and swap space sizing. The images below show a developer machine that is running a dev environment in WSL2 and Docker Desktop.  Docker Desktop has two of its own WSL modules that need to be accounted for.  You can see that the memory would actually be oversubscribed, 3 x 50% if every VM used its maximum memory.  The actual amount of memory used is significantly smaller allowing every piece to fit. Click to Enlarge The second drawing shows the memory allocation on my 64GB laptop. WSL Linux defaul...
Read more

Almost PaaS Document Parsing with Tika and AWS Elastic Beanstalk

Image
The Apache Tika project provides a  library capable of parsing and extracting data and meta data from over 1000 file types.  Tika is available as a single jar file that can be included inside applications or as a deployable jar file that runs Tika as a standalone service. This blog describes deploying the Tika jar as an auto-scale service in Amazon AWS Elastic Beanstalk.  I selected Elastic Beanstalk because it supports jar based deployments without any real Infrastructure configuration. Elastic Beanstalk auto-scale should take care of scaling up and down for for the number of requests you get. Tika parses documents and extracts their text completely in memory. Tika was deployed for this blog using EC2 t2.micro instances available in the AWS free tier. t2.micro VMs are 1GB which means that you are restricted in document complexity and size. You would size your instances appropriately for your largest documents.   Preconditions An AWS account. AWS ac...
Read more