Troubleshooting High-Speed Data Service

When using a digital signal analyzer to troubleshoot data throughput in the Data Over Cable Service Interface Specification (DOCSIS) network, what is the minimum modulation error ratio (MER) into the cable modem for a 256-QAM carrier?

32 dB or greater.

What would be the downstream throughput if two 256-QAM channels with a throughput of 38 megabits per second (Mbps) were bonded?

76 Mbps

In a Data Over Cable Service Interface Specification (DOCSIS) network, why is the data throughput over the return or upstream path typically less than the throughput of data over the forward or downstream path?

Compared to the downstream path, the narrower bandwidths and lower orders of modulation used to transport data over the return path cause the downstream and upstream data throughput to be unequal or asymmetrical.

How does Internet protocol (IP) multicast differ from IP broadcast?

IP multicast traffic is only sent to specific modem addresses on the network; IP broadcast traffic is sent to all modems on the network.

What Internet protocol (IP) address modes can a Data Over Cable Service Interface Specification (DOCSIS) 3.0 and 3.1 modem be provisioned in?

IP version 4 (IPv4), IP version 6 (IPv6), alternate provisioning mode (APM), and dual-stack provisioning mode (DPM).

What are two features that were added in Data Over Cable Service Interface Specification (DOCSIS) 3.1 to extend the viability of hybrid fiber/coax (HFC) networks into the next decade?

Orthogonal frequency division multiplexing (OFDM) and low-density parity-check (LDPC).

Which step in the troubleshooting process requires a discussion with the customer to gather more detail about the problem?

Step 1: Identify the problem.

Which Data Over Cable Service Interface Specification (DOCSIS) layer is used by the cable modem termination system (CMTS) to differentiate between cable modems?

The DOCSIS Media Access Control (MAC) Layer.

What was done in Data Over Cable Service Interface Specification (DOCSIS) 3.0 to allow enough bandwidth for upstream carriers from previous DOCSIS versions?

The option to increase the top frequency of the upstream to 85 MHz.

When analyzing a problem, what can the technician learn by asking the customer to show or demonstrate the problem?

The symptoms of the problem can be viewed and any unusual screens or customer entries can be identified.