Here you will find answer to CCNA - IPv6 questions
Question 1
As a CCNA candidate, you must have a firm understanding of the IPv6 address structure. Refer to IPv6 address, could you tell me how many bits are included in each filed?
A - 24
B - 4
C - 3
D - 16
Answer: D
Explanation:
The format of a IPv6 address is X:X:X:X:X:X:X:X where X is a 16-bit hexadecimal field. For example: 110A:0192:190F:0000:0000:082C:875A:132c
Question 2
In practical IPv6 application, a technology encapsulates IPv6 packets inside IPv4 packets, this technology is called what?
A - tunneling
B - hashing
C - routing
D - NAT
Answer: A
Question 3
Internet Protocol version 6 (IPv6) is the next-generation Internet Protocol version designated as the successor to IPv4 because IPv4 address space is being exhausted. Which one of the following descriptions about IPv6 is correct?
A - Addresses are not hierarchical and are assigned at random.
B - Broadcasts have been eliminated and replaced with multicasts.
C - There are 2.7 billion available addresses.
D - An interface can only be configured with one IPv6 address.
Answer: B
Question 4
Which two of these statements are true of IPv6 address representation? (Choose two)
A - The first 64 bits represent the dynamically created interface ID.
B - A single interface may be assigned multiple IPV6 addresses of any type.
C - Every IPV6 interface contains at least one loopback address.
D - Leading zeros in an IPV6 16 bit hexadecimal field are mandatory.
Answer: B C
Explanation:
Leading zeros in IPv6 are optional do that 05C7 equals 5C7 and 0000 equals 0 -> D is not corect.
Question 5
Which three of the following are IPv6 transition mechanisms? (Choose three)
A - 6to4 tunneling
B - GRE tunneling
C - ISATAP tunneling
D - Teredo tunneling
E - VPN tunneling
F - PPP tunneling
Answer: A C D
Explanation:
Below is a summary of IPv6 transition technologies:
6 to 4 tunneling: This mechanism allows IPv6 sites to communicate with each other over the IPv4 network without explicit tunnel setup. The main advantage of this technology is that it requires no end-node reconfiguration and minimal router configuration but it is not intended as a permanent solution.
ISATAP tunneling (Intra-Site Automatic Tunnel Addressing Protocol): is a mechanism for transmitting IPv6 packets over IPv4 network. The word "automatic" means that once an ISATAP server/router has been set up, only the clients must be configured to connect to it.
Teredo tunneling: This mechanism tunnels IPv6 datagrams within IPv4 UDP datagrams, allowing private IPv4 address and IPv4 NAT traversal to be used.
In fact, GRE tunneling is also a IPv6 transition mechanism but is not mentioned in CCNA so we shouldn't choose it (there are 4 types of IPv6 transition mechanisms mentioned in CCNA; they are: manual, 6-to-4, Teredo and ISATAP).
Question 6
Which two descriptions are correct about characteristics of IPv6 unicast addressing? (Choose two)
A - Global addresses start with 2000::/3.
B - Link-local addresses start with FF00::/10.
C - Link-local addresses start with FE00:/12.
D - There is only one loopback address and it is ::1.
Answer: A D
Explanation:
Below is the list of common kinds of IPv6 addresses:
| Loopback address | ::1 |
| Link-local address | FE80::/10 |
| Site-local address | FEC0::/10 |
| Global address | 2000::/3 |
| Multicast address | FF00::/8 |
(For more explanation about this question please read question 5 in http://9tut.net/ccna-operations)
Question 7
Select the valid IPv6 addresses. (Choose all apply)
A - ::192:168:0:1
B - 2002:c0a8:101::42
C - 2003:dead:beef:4dad:23:46:bb:101
D - ::
E - 2000::
F - 2001:3452:4952:2837::
Answer: A B C D F
Explanation:
Answers A B C are correct because A and B are the short form of 0:0:0:0:192:168:0:1 and 2002:c0a8:0101:0:0:0:0:0042 while C are normal IPv6 address.
Answer D is correct because "::" is named the "unspecified" address and is typically used in the source field of a datagram that is sent by a device that seeks to have its IP address configured.
Answer E is not correct because a global-unicast IPv6 address is started with binary 001, denoted as 2000::/3 in IPv6 and it also known as an aggregatable global unicast address.The 2000:: (in particular, 2000::/3) is just a prefix and is not a valid IPv6 address.
The entire global-unicast IPv6 address range is from 2000::/128 to 3FFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF/128, resulting in a total usable space of over 42,535,295,865,117,307,932,921,825,928,971,000,000 addresses, which is only 1/8th of the entire IPv6 address space!
