CDN API Gateway & Rate Limiting 3

Question 1

Which leaky bucket characteristic differentiates it from the token bucket algorithm?

Accepted Answer

Leaky bucket enforces a constant output rate; token bucket permits bursts up to capacity

Answer

The leaky bucket processes requests at a fixed constant rate regardless of input bursts, while the token bucket allows short bursts up to the bucket size.

Question 2

An API gateway must route requests to different CDN origin clusters based on the API version in the URL path. What is this pattern called?

Accepted Answer

Path-based routing

Answer

Path-based routing directs traffic to different backends based on URL path segments, such as /v1/ or /v2/.

Question 3

What does the Retry-After response header communicate to an API client after a 429 response?

Accepted Answer

How many seconds or a date until the client can retry

Answer

Retry-After tells the client either a delay in seconds or an HTTP-date after which it may safely retry the request.

Question 4

Which security threat does an API gateway's rate limiter most directly mitigate against CDN infrastructure?

Accepted Answer

Credential stuffing and brute force attacks

Answer

Rate limiting restricts the number of login or token attempts, directly throttling credential stuffing and brute force attacks.

Question 5

A CDN's API gateway implements mutual TLS (mTLS). What does the gateway verify in addition to the server certificate?

Accepted Answer

The client's certificate during the TLS handshake

Answer

In mTLS, both parties present certificates; the gateway verifies the client certificate to ensure only authorized clients connect.

(CDN) Content Delivery Network Certification Practice Test

(CDN) Content Delivery Network Certification Practice Test

CDN API Gateway & Rate Limiting 3