ISTM 210 Key Terms

Chapter Review QUIZZES

Systems Development Life Cycle (SDLC)

End-to-end process for developing an information system, from planning through maintenance; includes hardware, people, and processes.

Seven SDLC Phases

Planning, Analysis, Design, Development, Testing, Implementation, Maintenance.

Planning Phase Output

Formal management approval to proceed and a high-level requirements matrix.

Analysis Phase Output

Requirements definition document.

Design Phase Output

Detailed models and specifications.

Development Phase Output

Working prototype.

As-Is Process

How a process actually works today, including hidden steps and workarounds.

To-Be Process

How a process should work after the change.

Why Document As-Is Before To-Be?

To understand the real current process and identify gaps that become requirements.

Waterfall Development

Runs phases once in strict order with heavy upfront planning; best suited to stable, fixed-scope requirements.

Agile Development

Repeats work in short sprints with continuous feedback; adapts to changing requirements.

Choosing a Development Method

Ask how stable the requirements are and how expensive a late change would be.

Agile Trade-Off

Flexibility and less discarded work, but recurring planning, demos, client involvement, backlog decisions, and possible rework.

Testable Requirement

A requirement with measurable conditions that allow a test to determine whether it is satisfied.

Functional Requirement

Specifies what the system does, such as calculating sales tax.

Non-Functional Requirement

Specifies how well the system performs, such as response time, capacity, or uptime.

User Story Format

As a [role], I want [capability], so that [benefit].

Acceptance Criteria

Specific, checkable conditions that determine whether a user story is satisfied.

Say-Do Gap

The difference between how people describe their work and how they actually perform it.

MoSCoW Prioritization

Must have, Should have, Could have, Won't have this time.

Traceability

Links each requirement to its source or process gap and the future test that verifies it.

Packet Switching

Breaks messages into independently routed packets carrying destination addresses and sequence numbers; packets are reassembled at the destination.

Advantages of Packet Switching

Shares network capacity across conversations and allows packets to route around failures.

TCP

Provides reliable delivery by numbering and acknowledging packets, retransmitting missing ones, and reassembling data.

DNS Lookup

Translates a domain name into the address needed to reach its destination through a chain of queries.

DNS Caching

Stores DNS answers temporarily, so old and new records may coexist for hours after a change.

Network Troubleshooting Questions

Do other devices work? Can anything connect? Does the router report an upstream outage? Do all sites fail?

HTTPS

Encrypts content in transit but does not hide all connection metadata or guarantee a website is trustworthy.

Facebook Outage

Routing announcements were withdrawn, making Facebook's networks and DNS servers unreachable even though its servers were still running.

Dynamic Website Request Path

DNS → internet routing → optional firewall/gateway → web application → optional database.

Actual Domain Owner in paypal.com.secure-billing.net

secure-billing.net; the registrable domain identifies the actual domain owner.

HTTP GET

Requests a representation and is intended to be safe.

HTTP POST

Submits data for processing.

HTTP 2xx

Status codes indicating success.

HTTP 3xx

Status codes indicating redirection.

HTTP 4xx

Status codes indicating the request was rejected or could not be fulfilled.

HTTP 5xx

Status codes indicating a server failure while handling an apparently valid request.

HTTP Statelessness

HTTP does not automatically retain request context between separate exchanges.

Cookie and Session

The browser stores a session identifier in a cookie; the server uses it to recognize later requests.

Infrastructure as a Service (IaaS)

Rent virtual machines and storage; the customer manages the operating system and higher layers.

Platform as a Service (PaaS)

The provider manages infrastructure and runtime, letting the customer focus on application code.

Software as a Service (SaaS)

The provider runs and delivers a complete application.

Public Cloud

Cloud infrastructure shared across customers; useful for workloads such as spiky ticket sales.

Private Cloud or Isolated Deployment

Dedicated or isolated infrastructure suited to requirements such as sensitive hospital records.

Hybrid Cloud

Combines environments, such as a legacy factory system with a new mobile application.

Reserved Cloud Capacity

Capacity planned for predictable, year-round baseline demand.

On-Demand Cloud Capacity

Flexible capacity used to handle demand spikes.

Spot Cloud Capacity

Discounted, interruptible capacity suited to work that can tolerate interruptions.

Cloud Computing Benefits

Faster provisioning, elasticity, and global reach.

Cloud Computing Trade-Offs

Recurring costs, less control over incident timing, and concentration risk.

Recovery Time Objective (RTO)

How long the business can afford to be down.

Recovery Point Objective (RPO)

How much recent data the business can afford to lose.

HTML Structure

HTML declares what each piece of content is, not how it looks.

Structural HTML Elements

h1 = heading; p = paragraph; ul/li = list and list items; header/main = page regions.

Semantic Heading

A heading marked in HTML that contributes to the page outline, not just text that looks large.

HTML Validation

Checks HTML for syntax errors, mis-nested or unclosed tags, and missing required attributes.

href Attribute

Specifies a link destination, such as an absolute URL, relative path, or on-page anchor.

Absolute URL

A complete address pointing to a destination on another site.

Relative Path

A path to a file or page based on the current file's folder.

On-Page Anchor (#id)

A link to an element with a matching ID on the same page.

Descriptive Link Text

Text that clearly communicates where a link leads, helpful for screen readers; better than vague text like "click here."

alt Attribute

Text read in place of an image by screen readers and used by search engines to interpret the image.

Relative Path: about.html

Refers to a file in the same folder as the current file.

Relative Path: ../

Goes up one folder to a parent directory.

Relative Path: images/logo.png

Goes down into the images subfolder to locate logo.png.

Why Relative Paths Matter

Incorrect paths can create dead links or broken images.

Connecting a Label to a Field

Match the label's for attribute to the field's id attribute.

HTML Input Type

Specifies the kind of data a field accepts, such as email, number, or date.

Form Field name Attribute

Provides the key in the name/value pair submitted with the form.

select Element

Provides a control for choosing from constrained, predefined options.

textarea Element

Provides a control for entering free-form or longer text.

HTML Table

Uses elements such as table, tr, th, and td to organize related data into rows and columns.

Why Avoid Tables for Page Layout?

Layout tables can confuse screen readers and break on small screens.

HTML Element h1

Marks a top-level heading in the document structure.

HTML Element p

Marks a paragraph of text.

HTML Element ul

Defines an unordered list containing list items.

HTML Element li

Defines an individual list item; <ul> and <ol> must only directly contain <li>

Browser, Screen Reader, Crawler, Script

Four types of tools that benefit from correct HTML structure and nesting.

HTML Accessibility: Links

Link text should explain the destination because screen reader users may hear links without surrounding context.

HTML Accessibility: Images

Alt text should explain an image's meaning in context; decorative images should use empty alt text.

Form Control Selection

Use an appropriate input type for the data, select for fixed choices, and textarea for free text.

HTML Table Elements

table = table; tr = row; th = header cell; td = data cell.