CDN EXAM 2026 - COMPLETE TEST BANK WITH 150
REAL EXAM QUESTIONS & VERIFIED ANSWERS
CDN EXAM 2026
Complete Test Bank — 150 Exam-Style Questions with Answers & Rationales
Study Resource Edition: Updated 2026/2027
Resource Type: Complete Practice Exam & Test Bank
Focus: Content Delivery Networks, Web Performance, Caching, Routing, Security,
and Distributed Delivery
ACADEMIC NOTICE: THIS DOCUMENT IS AN ORIGINAL PRACTICE
AND REVISION RESOURCE
Table of Contents
1. Introduction — Questions 1–20
2. Core Concepts — Questions 21–60
3. Applied Scenarios — Questions 61–95
4. Critical Thinking — Questions 96–125
5. Review Questions — Questions 126–150
6. Answer & Rationale Reference
SECTION 1 — INTRODUCTION
Question 1
What is the primary purpose of a Content Delivery Network (CDN)?
A. To replace an application's database
B. To deliver content from geographically distributed edge locations
C. To eliminate the need for DNS
D. To encrypt every database record
Correct answer: B
,Rationale: A CDN distributes cached or dynamically generated content across edge locations
positioned closer to end users. This reduces network distance and can improve latency,
availability, and scalability. A CDN does not replace a database or eliminate DNS.
Question 2
What is an edge server?
A. A database administrator's workstation
B. A server located close to end users that can process or serve requests
C. The application's only origin server
D. A DNS root server
Correct answer: B
Rationale: Edge servers are distributed infrastructure points that handle requests nearer to users.
They can serve cached content and, depending on the CDN, execute edge logic or proxy requests
toward the origin.
Question 3
What is the origin server?
A. The authoritative source from which the CDN obtains content
B. The user's browser
C. A DNS resolver
D. A cache-control header
Correct answer: A
Rationale: The origin is the backend source of content, such as a web server, object-storage
service, or application platform. When requested content is not available at the edge, the CDN
can retrieve it from the origin.
Question 4
What happens during a cache hit?
A. The CDN must always contact the origin
B. The requested object is available in the relevant cache and can be served there
C. The user's DNS configuration is deleted
D. The origin is permanently disabled
Correct answer: B
Rationale: A cache hit means the requested representation is present and considered usable in
the CDN cache. Serving it directly from the edge avoids an origin retrieval and normally reduces
latency and origin load.
,Question 5
What is a cache miss?
A. A request that cannot be served from the applicable cache
B. A successful browser cache lookup
C. A DNS query with no hostname
D. A TLS certificate renewal
Correct answer: A
Rationale: A cache miss occurs when an object is absent, expired, invalidated, or otherwise not
eligible to be served from cache. The CDN generally needs to obtain or generate the response
from another layer, often the origin.
Question 6
Which metric commonly measures the proportion of requests served from cache?
A. Cache hit ratio
B. Packet TTL
C. CPU clock rate
D. DNS recursion depth
Correct answer: A
Rationale: Cache hit ratio is commonly calculated as cache hits divided by relevant cacheable
requests. A higher ratio can indicate that the CDN is successfully reducing origin requests,
although the ideal value depends on workload and caching policy.
Question 7
Why can a CDN reduce latency?
A. It makes all application code execute instantly
B. It can serve content from infrastructure geographically closer to users
C. It removes the need for HTTP
D. It increases the physical speed of light
Correct answer: B
Rationale: Physical and routing distance contribute to network latency. By serving content from
a nearby edge location, a CDN can shorten the path between the user and the serving
infrastructure.
Question 8
Which content is traditionally well suited to CDN caching?
, A. Frequently changing database transactions
B. Static images, CSS, JavaScript, and other cacheable assets
C. Private banking account records
D. Password databases
Correct answer: B
Rationale: Static assets often have identical representations for many users and can therefore be
cached efficiently. Sensitive or highly personalized information generally requires more careful
cache-control policies.
Question 9
What does TTL commonly mean in caching?
A. Transfer Timing Layer
B. Time To Live
C. Trusted Transport Link
D. Traffic Transfer Limit
Correct answer: B
Rationale: TTL specifies how long a cached object may remain fresh under a particular caching
policy. Once freshness expires, the CDN may revalidate or retrieve the object again.
Question 10
Which HTTP header is particularly important for controlling browser and intermediary
caching?
A. Cache-Control
B. Hostname
C. User-Agent-Name
D. Content-Length-Policy
Correct answer: A
Rationale: Cache-Control provides directives such as max-age, no-store, private, and public that
influence caching behavior. Correct cache directives are essential for preventing stale or sensitive
content from being incorrectly cached.
Question 11
What is the main function of a CDN's caching layer?
Correct answer: Store eligible content temporarily so subsequent requests can be served
without repeatedly contacting the origin.
REAL EXAM QUESTIONS & VERIFIED ANSWERS
CDN EXAM 2026
Complete Test Bank — 150 Exam-Style Questions with Answers & Rationales
Study Resource Edition: Updated 2026/2027
Resource Type: Complete Practice Exam & Test Bank
Focus: Content Delivery Networks, Web Performance, Caching, Routing, Security,
and Distributed Delivery
ACADEMIC NOTICE: THIS DOCUMENT IS AN ORIGINAL PRACTICE
AND REVISION RESOURCE
Table of Contents
1. Introduction — Questions 1–20
2. Core Concepts — Questions 21–60
3. Applied Scenarios — Questions 61–95
4. Critical Thinking — Questions 96–125
5. Review Questions — Questions 126–150
6. Answer & Rationale Reference
SECTION 1 — INTRODUCTION
Question 1
What is the primary purpose of a Content Delivery Network (CDN)?
A. To replace an application's database
B. To deliver content from geographically distributed edge locations
C. To eliminate the need for DNS
D. To encrypt every database record
Correct answer: B
,Rationale: A CDN distributes cached or dynamically generated content across edge locations
positioned closer to end users. This reduces network distance and can improve latency,
availability, and scalability. A CDN does not replace a database or eliminate DNS.
Question 2
What is an edge server?
A. A database administrator's workstation
B. A server located close to end users that can process or serve requests
C. The application's only origin server
D. A DNS root server
Correct answer: B
Rationale: Edge servers are distributed infrastructure points that handle requests nearer to users.
They can serve cached content and, depending on the CDN, execute edge logic or proxy requests
toward the origin.
Question 3
What is the origin server?
A. The authoritative source from which the CDN obtains content
B. The user's browser
C. A DNS resolver
D. A cache-control header
Correct answer: A
Rationale: The origin is the backend source of content, such as a web server, object-storage
service, or application platform. When requested content is not available at the edge, the CDN
can retrieve it from the origin.
Question 4
What happens during a cache hit?
A. The CDN must always contact the origin
B. The requested object is available in the relevant cache and can be served there
C. The user's DNS configuration is deleted
D. The origin is permanently disabled
Correct answer: B
Rationale: A cache hit means the requested representation is present and considered usable in
the CDN cache. Serving it directly from the edge avoids an origin retrieval and normally reduces
latency and origin load.
,Question 5
What is a cache miss?
A. A request that cannot be served from the applicable cache
B. A successful browser cache lookup
C. A DNS query with no hostname
D. A TLS certificate renewal
Correct answer: A
Rationale: A cache miss occurs when an object is absent, expired, invalidated, or otherwise not
eligible to be served from cache. The CDN generally needs to obtain or generate the response
from another layer, often the origin.
Question 6
Which metric commonly measures the proportion of requests served from cache?
A. Cache hit ratio
B. Packet TTL
C. CPU clock rate
D. DNS recursion depth
Correct answer: A
Rationale: Cache hit ratio is commonly calculated as cache hits divided by relevant cacheable
requests. A higher ratio can indicate that the CDN is successfully reducing origin requests,
although the ideal value depends on workload and caching policy.
Question 7
Why can a CDN reduce latency?
A. It makes all application code execute instantly
B. It can serve content from infrastructure geographically closer to users
C. It removes the need for HTTP
D. It increases the physical speed of light
Correct answer: B
Rationale: Physical and routing distance contribute to network latency. By serving content from
a nearby edge location, a CDN can shorten the path between the user and the serving
infrastructure.
Question 8
Which content is traditionally well suited to CDN caching?
, A. Frequently changing database transactions
B. Static images, CSS, JavaScript, and other cacheable assets
C. Private banking account records
D. Password databases
Correct answer: B
Rationale: Static assets often have identical representations for many users and can therefore be
cached efficiently. Sensitive or highly personalized information generally requires more careful
cache-control policies.
Question 9
What does TTL commonly mean in caching?
A. Transfer Timing Layer
B. Time To Live
C. Trusted Transport Link
D. Traffic Transfer Limit
Correct answer: B
Rationale: TTL specifies how long a cached object may remain fresh under a particular caching
policy. Once freshness expires, the CDN may revalidate or retrieve the object again.
Question 10
Which HTTP header is particularly important for controlling browser and intermediary
caching?
A. Cache-Control
B. Hostname
C. User-Agent-Name
D. Content-Length-Policy
Correct answer: A
Rationale: Cache-Control provides directives such as max-age, no-store, private, and public that
influence caching behavior. Correct cache directives are essential for preventing stale or sensitive
content from being incorrectly cached.
Question 11
What is the main function of a CDN's caching layer?
Correct answer: Store eligible content temporarily so subsequent requests can be served
without repeatedly contacting the origin.
