Networking & IPv6

Question 1

In a /27 subnet and a Subnet Mask of 255.255.255.224, the customer has how many Public Routable IP addresses?

Answer 1

29 Public Routable IP Addresses

Question 2

How many times in an IPv6 address can you use the double colon to omit zeroes?

Answer 2

Only once

Question 3

In a /30 subnet and a Subnet Mask of 255.255.255.252, the customer has how many Public Routable IP addresses?

Answer 3

1 Public Routable IP Address

Question 4

In a /29 subnet and a Subnet Mask of 255.255.255.248, the customer has how many Public Routable IP addresses?

Answer 4

5 Public Routable IP Addresses

Question 5

How many addresses is IPv6 capable of?

Answer 5

Approximately 3.4E+11 or 340 undecillion

Question 6

An IP address in the range of 128-191.X.X.X is what class of IP address?

Answer 6

Class B Public

Question 7

Comcast is migrating to this version of IP which will allow for nearly unlimited IP addresses.

Answer 7

IPv6

Question 8

192.168.X.X is an example of what class of IP address?

Answer 8

Class C Private

Question 9

What types of addresses does IPv6 support?

Answer 9

Unicast addresses and multicast addresses

Question 10

Where can a customer go to see what their IPv6 address is?

Answer 10

www.comcast6.net

Question 11

What does DHCP stand for?

Answer 11

Dynamic Host Configuration Protocol

Question 12

10.1.X.X is an example of what class of IP address?

Answer 12

Class A Private

Question 13

An IP address in the range of 192-223.X.X.X is what class of IP address?

Answer 13

Class C Public

Question 14

In a /28 subnet and a Subnet Mask of 255.255.255.240, the customer has how many Public Routable IP addresses?

Answer 14

13 Public Routable IP Addresses

Question 15

What are the two currently used COMCAST DNS’s?

Answer 15

75.75.75.75 and 75.75.76.76

Question 16

What is the simplified version of the following IPv6 address? FE80:CD00:0000:0000:0000:0000:211E:729C

Answer 16

FE80:CD00::211E:729C

Question 17

In IPv6, what is Duplicate Address Detection?

Answer 17

It is a mechanism that detects duplicate addresses on a subnet

Question 18

What are the advantages of IPv6?

Answer 18

Simplified header format for efficient packet handling
Larger payload for increased throughput and transport efficiency
Hierarchical network architecture for routing efficiency
Support for widely deployed routing protocols (OSPF, BGP, etc.)
Autoconfiguration and plug-and-play support
Elimination of need for network address translation (NAT) and application layered gateway (ALG)
Increased number of multicast addresses

Question 19

How many bits is the address field for IPv6?

Answer 19

128

Question 20

An IP address in the range of: 1-127.X.X.X is what class of IP address?

Answer 20

Class A Public

Question 21

Comcast is continuing to provide an IPv4 address to each customer and is now additionally providing IPv6 addresses. What is this approach referred to?

Answer 21

Dual Stack Mode

Question 22

What is dual stack mode?

Answer 22

When IPv4 and IPv6 run on the same network infrastructure

Question 23

One way technicians can tell if an IPv6 compatible modem is having an issue related to IPv6 and is ranging is because “this” modem light will continue to blink.

Answer 23

Online

Question 24

What is the loopback address for IPv6?

Answer 24

0000:0000:0000:0000:0000:0000:0000:0001

or ::1

Question 25

This tool in the National CMTS Operations Portal can be used by a field technician to verify a CMTS is set for IPv6, then switch the cable-mac that the modem is on to IPv4.

Answer 25

IPv6 to IPv4 MAC Switcher

Question 26

How are IPv6 addresses written or expressed?

Answer 26

In 8 groups of 4 hexadecimal digits separated by colons

Question 27

Why don’t you need a traditional subnet mask for IPv6?

Answer 27

The subnet ID is built into the address