Troubleshooting High Speed Data Service
What does asymmetric data throughput mean?
Asymmetrical or unequal downstream and upstream data rates are caused by the narrower bandwidth and lower orders of modulation.
Why is the throughput measurement test a valid measurement of a networks performance?
Because the throughput can be compromised by traffic congestion and errors introduced during transport, the throughput measurement is an effective measurement of the networks's technical integrity.
What is the difference between the broadcast and multicast adressing schemes?
Broadcast is a one-to-all adressing scheme in which one device sends the same stream of data to an address that all connected devices can recieve. Multicast is a one-to-many communications protocol that simultaneously delivers a single stream of information to multiple addressed devices on a network.
What are the main components of the DOCSIS architecture?
Cable Modem and Cable Modem Termination Service
Which DOCSIS version provided the option to increase the top frequency of the upstream to 85 MHz, and bumped the downstream range to 108 MHz to 1,002?
DOCSIS 3.0 provided the option to increase the top frequency of the upstream to 85 MHz, and bumped the downstream range from 108 MHz to 1,002 MHz.
What is the value of the cable modem status indicators?
Each indicator can serve multiple purposes during the modem's power-up , initialiation, and operation sequences.
What is the logical place to begin applying the divide - and-conquer method to an HSD problem in the customer premise.
HSD service to a customer premise begins at the service tap and terminates in the customer premises equipment (CPE), such as a computer.
If 8 QAM channels are bonded, what is the maximum possible downstream throughput?
If 8 QAM channels are bonded, the maximum possible downstream throughput is 308 Mbps.
What can cause the data throughput speeds to vary at different times during the day?
Many factors can contribute to slow throughput such as content delivery network (CDN) speeds, noise or ingress in the broadband network, excessive network traffic, high transmit levels or low receive levels which cause the modem to re-transmit data, or the customer's LAN or computer speed.
What is the relationship between adjacent orthogonal frequency division multiplexing (OFDM) subcarriers?
OFDM is a transmission scheme in which several independent narrowband carriers (subcarriers) are modulated at a low data rate. The peak power of each subcarrier aligns with the maximum power of the adjacent subcarrier, or orthogonal.
Which layer specifies the modulation and access techniques for communications over an HFC network?
Physical Layer
How much do you know about the DOCSIS architecture?
The client (cable modem)/server (CMTS) model is employed in the Data Over Cable Service Interface Specification (DOCSIS) architecture to describe the cable modem termination system (CMTS) and cable modem relationship. In the DOCSIS architecture, the CMTS is the server. In the DOCSIS architecture, the cable modem at the customer premises is considered the client.
Which step of the six-step troubleshooting process requires a discussion with the customer to gather more detail about the problem
The first step, identify the problem, requires a discussion with the customer to gather more detail about the problem
What information should be gathered before beginning to troubleshoot a high speed data (HSD) problem?
When receiving a work order for an HSD service trouble call, the technician is typically provided with informaton from a customer service representative (CSR) about the problem.
What seven layers of the Open Systems Interconnection (OSI) reference model are present in the DOCSIS implementation?
Within the DOCSIS implementation of the OSI model, layers one through four are specific to cable networks and are present only between the cable modem and the CMTS.
