Chapter 4

1:
What are the downstream and upstream frequency allocations?
A1:
Answer: The DOCSIS upstream frequency is from 5 to 42 MHz. The DOCSIS downstream frequency is from 88 to 860 MHz.
2:
What type of modulation methods are used for the upstream and downstream?
A2:
Answer: For the upstream, QPSK or 16-QAM is used. For the downstream, 64-QAM or 256-QAM is used.
3:
What servers are required for the cable access solution to work?
A3:
Answer: The DHCP, ToD, and TFTP servers are required.
4:
What are the minimum configuration requirements for the CMTS?
A4:
Answer:

Set the upstream frequency

Enable the upstream port

Configure the IP address(es)

Configure the helper address
5:
What MPEG framing format is used in North America?
Annex A
Annex B
Annex C
A5:
Answer: B
6:
What configuration is recommended to deal with upstream noise and interference?
A6:
Answer: Spectrum management or advanced spectrum management if a Cisco MC16S cable modem card is used.
7:
What is the correct syntax to activate upstream port 2 of the cable modem card in slot 4?
interface cable 4/2 upstream no shutdown
interface cable 4/0 no cable upstream 2 shutdown
interface cable 2/0 upstream no shutdown
A7:
Answer: B
8:
What is the default operating mode of a Cisco cable access router?
A8:
Answer: Plug-and-play DOCSIS-compliant bridging mode.
9:
What are the required steps to configure the routing mode on the cable access router?
A9:
Answer:

Enable IP routing.
Use the no cable-modem compliant bridge interface command to disable DOCSIS-compliant bridging on the cable interface.
Remove the bridge group on the cable and Ethernet interfaces with the no bridge-group interface command.
Configure a routing protocol, such as RIP version 2.
10:
What command can be used at the CMTS to see the flapping cable modems?
A10:
Answer: show cable flap-list
11:
What command can be used at the CMTS to find out the registered and unregistered cable modems?
A11:
Answer: show cable modem

[ LiB ]

1:	What are the downstream and upstream frequency allocations?
A1:	Answer: The DOCSIS upstream frequency is from 5 to 42 MHz. The DOCSIS downstream frequency is from 88 to 860 MHz.
2:	What type of modulation methods are used for the upstream and downstream?
A2:	Answer: For the upstream, QPSK or 16-QAM is used. For the downstream, 64-QAM or 256-QAM is used.
3:	What servers are required for the cable access solution to work?
A3:	Answer: The DHCP, ToD, and TFTP servers are required.
4:	What are the minimum configuration requirements for the CMTS?
A4:	Answer: Set the upstream frequency Enable the upstream port Configure the IP address(es) Configure the helper address
5:	What MPEG framing format is used in North America? Annex A Annex B Annex C
A5:	Answer: B
6:	What configuration is recommended to deal with upstream noise and interference?
A6:	Answer: Spectrum management or advanced spectrum management if a Cisco MC16S cable modem card is used.
7:	What is the correct syntax to activate upstream port 2 of the cable modem card in slot 4? interface cable 4/2 upstream no shutdown interface cable 4/0 no cable upstream 2 shutdown interface cable 2/0 upstream no shutdown
A7:	Answer: B
8:	What is the default operating mode of a Cisco cable access router?
A8:	Answer: Plug-and-play DOCSIS-compliant bridging mode.
9:	What are the required steps to configure the routing mode on the cable access router?
A9:	Answer: Enable IP routing. Use the no cable-modem compliant bridge interface command to disable DOCSIS-compliant bridging on the cable interface. Remove the bridge group on the cable and Ethernet interfaces with the no bridge-group interface command. Configure a routing protocol, such as RIP version 2.
10:	What command can be used at the CMTS to see the flapping cable modems?
A10:	Answer: show cable flap-list
11:	What command can be used at the CMTS to find out the registered and unregistered cable modems?
A11:	Answer: show cable modem