CST CST Storage & Retention Management 1 — Questions and Answers
Question 1: What does DVR stand for in a surveillance system?
- Digital Video Recorder (Correct answer)
- Direct Video Router
- Data Verification Router
- Dual Video Relay
Correct answer: Digital Video Recorder
A DVR (Digital Video Recorder) captures and stores video from analog cameras by digitizing the signal internally.
Question 2: What is the primary advantage of an NVR over a DVR for modern surveillance installations?
- NVRs are less expensive than DVRs
- NVRs process video data from IP cameras directly over the network (Correct answer)
- NVRs only support analog cameras
- NVRs do not require hard drives
Correct answer: NVRs process video data from IP cameras directly over the network
An NVR receives already-encoded digital video streams from IP cameras over the network, eliminating the need for analog encoding hardware.
Question 3: Which factor has the GREATEST impact on the storage capacity required for a surveillance system?
- The color of the camera housing
- The resolution, frame rate, and compression codec used (Correct answer)
- The length of the camera cable
- The type of camera mount
Correct answer: The resolution, frame rate, and compression codec used
Higher resolution, higher frame rates, and less efficient codecs all increase the storage space consumed per hour of recorded video.
Question 4: What is the purpose of motion-triggered recording in a surveillance storage strategy?
- To improve camera image quality during motion events
- To reduce storage usage by only recording when activity is detected (Correct answer)
- To automatically alert police when motion is detected
- To enable pan-tilt-zoom on fixed cameras
Correct answer: To reduce storage usage by only recording when activity is detected
Motion-triggered recording conserves storage by only writing video to disk when motion is detected rather than recording continuously.
Question 5: In surveillance storage planning, what does 'retention period' refer to?
- The time it takes to retrieve a video clip
- The length of time recorded footage is kept before being overwritten or deleted (Correct answer)
- The duration of a single camera's recording session
- The warranty period for the DVR/NVR
Correct answer: The length of time recorded footage is kept before being overwritten or deleted
Retention period defines how long video footage is stored before the system automatically overwrites or purges it.
Question 6: A surveillance system is configured for continuous recording at 1080p/15fps. What is the BEST approach to extend the retention period without adding storage hardware?
- Increase the frame rate to 30fps
- Switch to a more efficient codec such as H.265 (Correct answer)
- Disable all cameras during daytime hours
- Use JPEG instead of video compression
Correct answer: Switch to a more efficient codec such as H.265
H.265 (HEVC) provides approximately 50% better compression than H.264 at equivalent quality, effectively doubling storage efficiency.
CST CST Storage & Retention Management 1
What does DVR stand for in a surveillance system?