BDS Industry Standards and Regulations 2 — Questions and Answers
Question 1: What is the DOCSIS specification's requirement for cable modem downstream channel lock time during initialization?
- The modem must lock the downstream within 1 second
- The modem must scan and lock a downstream QAM channel within 30 seconds of power-on (Correct answer)
- The modem must achieve downstream lock within 5 minutes
- There is no specified time limit for downstream lock
Correct answer: The modem must scan and lock a downstream QAM channel within 30 seconds of power-on
DOCSIS specifications require that a cable modem complete downstream channel acquisition within 30 seconds after applying power, ensuring timely service restoration after power interruptions.
Question 2: What is SCTE-HMS (Headend Monitoring System) used for in cable operations?
- Managing subscriber account billing and service provisioning
- Providing a standardized SNMP MIB framework for monitoring headend and outside plant equipment health and alarms (Correct answer)
- Encrypting communications between the headend and cable modems
- Managing video-on-demand asset libraries and metadata
Correct answer: Providing a standardized SNMP MIB framework for monitoring headend and outside plant equipment health and alarms
SCTE-HMS defines standard SNMP MIB structures for monitoring cable headend equipment, power supplies, and outside plant devices, enabling interoperable network management across equipment from different vendors.
Question 3: What is the significance of FCC Part 15 regulations for cable broadband equipment?
- Part 15 regulates the licensing requirements for cable TV operators
- Part 15 sets limits on unintentional RF emissions from electronic devices, including cable modems and headend equipment, to prevent interference with licensed radio services (Correct answer)
- Part 15 specifies minimum broadband speeds that cable operators must deliver
- Part 15 governs the content regulations for cable television channels
Correct answer: Part 15 sets limits on unintentional RF emissions from electronic devices, including cable modems and headend equipment, to prevent interference with licensed radio services
FCC Part 15 establishes emission limits for unlicensed electronic devices; cable modems, set-top boxes, and headend equipment must be tested and certified to ensure their unintentional emissions don't interfere with licensed radio users.
Question 4: What does DOCSIS 3.0's channel bonding capability provide compared to DOCSIS 2.0?
- Improved encryption for subscriber data
- The ability to combine multiple downstream and upstream channels to achieve higher aggregate throughput (Correct answer)
- Support for IPv6 addressing for cable modems
- Reduced latency through improved QoS mechanisms
Correct answer: The ability to combine multiple downstream and upstream channels to achieve higher aggregate throughput
DOCSIS 3.0 introduced channel bonding, allowing cable modems to simultaneously use up to 8 downstream and 4 upstream QAM channels, multiplying throughput compared to DOCSIS 2.0's single-channel operation.
Question 5: What is the NCTA's role in the US cable broadband industry?
- To develop technical standards for cable equipment and systems
- To serve as the primary trade association representing cable operators before Congress and the FCC (Correct answer)
- To operate the DNS infrastructure for cable internet services
- To certify cable installers and technicians through standardized testing
Correct answer: To serve as the primary trade association representing cable operators before Congress and the FCC
The NCTA (National Cable and Telecommunications Association) is the principal trade organization representing US cable operators, advocating for the industry before Congress, the FCC, and in public policy debates.
Question 6: What is the purpose of SCTE 55-1 and SCTE 55-2 standards in cable systems?
- They define physical layer specifications for coaxial cable
- They specify the out-of-band digital transmission system for communicating with digital set-top boxes (Correct answer)
- They define DOCSIS upstream channel bonding requirements
- They specify fiber optic connector and splice performance requirements
Correct answer: They specify the out-of-band digital transmission system for communicating with digital set-top boxes
SCTE 55-1 (DVS 178) and SCTE 55-2 define two competing out-of-band (OOB) digital communication standards for delivering EPG, CAS, and control data to digital set-top boxes on cable systems.
BDS Industry Standards and Regulations 2
What is the DOCSIS specification's requirement for cable modem downstream channel lock time during initialization?