BDS Headend and Hub Site Equipment

Question 1

What is the primary function of a headend in a cable system?

Accepted Answer

To receive, process, and retransmit all cable signals including video, data, and voice for distribution to subscribers

Answer

To provide subscriber billing and account management

Answer

To house the fiber-to-coax conversion equipment for each neighborhood

Answer

To store all subscriber usage data locally

Question 2

What does a QAM modulator do in a cable headend?

Accepted Answer

It converts digital content streams into QAM-modulated RF carriers for downstream transmission

Answer

It demodulates incoming satellite signals

Answer

It monitors signal quality on all downstream channels

Answer

It encrypts video streams for conditional access

Question 3

What is the purpose of a signal combiner in a headend?

Accepted Answer

To merge multiple individual RF carriers onto a single broadband output for feeding the distribution plant

Answer

To amplify all channels before distribution

Answer

To split the headend output to multiple hub sites

Answer

To filter out ingress from the return path

Question 4

What is conditional access (CA) in cable video systems?

Accepted Answer

An encryption and authorization system that ensures only paying subscribers can view specific content

Answer

A physical security system that controls access to the headend facility

Answer

A DOCSIS feature that limits modem upstream access based on subscription tier

Answer

A method of remotely accessing headend equipment

Question 5

What does an IPQAM device do in a modern cable headend?

Accepted Answer

Converts IP video streams into QAM RF channels for video-on-demand or SDV services

Answer

Tests IP packet quality across the CMTS

Answer

Provides IP address allocation for set-top boxes

Answer

Monitors jitter and packet loss on the IP backbone

Question 6

What is an IRD (Integrated Receiver/Decoder) at a cable headend?

Accepted Answer

A device that receives and decodes satellite-delivered video programming for re-encoding and local transmission

Answer

An IP router with integrated DOCSIS card

Answer

A modem that integrates the CM and router functions

Answer

A rack unit that combines QAM modulator and encoder