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IPv6 Questions 3

October 28th, 2017 Go to comments

Note: If you are not sure about IPv6, please read our IPv6 tutorial.

Question 1

Explanation

A IPv6 Unique Local Address is an IPv6 address in the block FC00::/7, which means that IPv6 Unique Local addresses begin with 7 bits with exact binary pattern as 1111 110 -> Answer B is correct.

Note: IPv6 Unique Local Address is the approximate IPv6 counterpart of the IPv4 private address. It is not routable on the global Internet.

Question 2

Explanation

Neighbor Discovery Protocol is an umbrella that defines these mechanisms:
+ Subsitute of ARP – Since ARP has been removed in IPv6, IPv6 follows a newer way to find the link-layer addresses of nodes on the local link. This new mechanism uses a mix of ICMPv6 messages and multicast addresses

Reference: https://supportforums.cisco.com/document/77521/ipv6-neighbor-discovery-protocol-ndp

Question 3

Question 4

Explanation

Only three connection types are commonly known and used in Internet Protocol version four (IPv4) networks: unicast, multicast and broadcast. A fourth connection type, Anycast, was unknown until IPv6 made it a standard connection type. Anycast is not standardized in IPv4 but can be emulated. IPv4 Anycast addressing is a good solution to provide localization for services and servers in order to obtain robustness, redundancy and resiliency.

The basic idea of Anycast is very simple: multiple servers, which share the same IP address, host the same service. The routing infrastructure sends IP packets to the nearest server (according to the metric of the routing protocol used). The major benefits of employing Anycast in IPv4 are improved latency times, server load balancing, and improved security.

Reference: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.116.6367&rep=rep1&type=pdf

Question 6

Question 7

Explanation

Floating static routes are static routes that have an administrative distance greater than the administrative distance (AD) of another static route or dynamic routes. By default a static route has an AD of 1 then floating static route must have the AD greater than 1 -> Answer A is correct as it has the AD of 201.

Question 8

Explanation

Each ISP receives a /32 and provides a /48 for each site-> every ISP can provide 2(48-32) = 65,536 site addresses (note: each network organized by a single entity is often called a site).

ipv6_Address_Allocation_Policy.jpg

Each site provides /64 for each LAN -> each site can provide 2(64-48) = 65,536 LAN addresses for use in their private networks.
So each LAN can provide 264 interface addresses for hosts.

-> Global routing information is identified within the first 64-bit prefix.

Now let’s see an example of IPv6 prefix: 2001:0A3C:5437:ABCD::/64:

IPv6_prefix_length_example.jpg

In this example, the RIR has been assigned a 12-bit prefix. The ISP has been assigned a 32-bit prefix and the site is assigned a 48-bit site ID. The next 16-bit is the subnet field and it can allow 216, or 65536 subnets. This number is redundant for largest corporations on the world!

The 64-bit left (which is not shown the above example) is the Interface ID or host part and it is much more bigger: 64 bits or 264 hosts per subnet! For example, from the prefix 2001:0A3C:5437:ABCD::/64 an administrator can assign an IPv6 address 2001:0A3C:5437:ABCD:218:34EF:AD34:98D to a host.

Question 9

Explanation

Link-local addresses refer only to a particular physical link and are used for addressing on a single link for purposes such as automatic address configuration and neighbor discovery protocol. Link-local addresses can be used to reach the neighboring nodes attached to the same link. The nodes do not need a globally unique address to communicate. Routers will not forward datagram using link-local addresses. All IPv6 enabled interfaces have a link-local unicast address.

A link-local address is an IPv6 unicast address that can be automatically configured on any interface using the link-local prefix FE80::/10 (1111 1110 10) and the interface identifier in the modified EUI-64 format. Link-local addresses are not necessarily bound to the MAC address (configured in a EUI-64 format). Link-local addresses can also be manually configured in the FE80::/10 format using the “ipv6 address link-local” command.

Reference: http://www.cisco.com/c/en/us/support/docs/ip/ip-version-6-ipv6/113328-ipv6-lla.html

In summary, if you do not configure a link-local on an IPv6 enabled interface, it will automatically use the FE80::/10 and the interface identifier in the modified EUI-64 format to form a link-local address.

Question 10

 

Comments (21) Comments
  1. gigi
    June 21st, 2017

    please provide the link to 9tut Questions pdf.
    thank you!

  2. Michel
    June 30th, 2017

    Found this VCE with the CCNA questions, can anyone confirm if this are valid https://drive.google.com/open?id=0B5mAFqgydmCza1ViTmFlNkQwYzg

  3. Advice
    July 25th, 2017

    Question 1 answer isn’t written correctly. It show “1111 1100” instead of “1111 1110” like in the explanation.

  4. Advice
    July 25th, 2017

    Wait nvm I figured it out.

  5. nickaro
    August 15th, 2017

    As Advice says, in Q.1 there’s something wrong…

  6. nickaro
    August 15th, 2017

    Q.4 isn’t commented. What is seemed to be answer 4 comment, it is actually answer 5’s…

  7. Anonymous
    August 17th, 2017

    Hello am not able to see questions. yet i was seeing them yesterday when I paid membership.

  8. charles
    August 17th, 2017

    Hello am not able to see questions. yet i was seeing them yesterday when I paid membership

  9. 9tut
    August 17th, 2017

    @charles: If your problem still exists, please send an email to support@9tut.com so that we can help you.

  10. AN
    September 20th, 2017

    Q8 Must be C, F according to:
    https://tools.ietf.org/html/rfc4193
    (Section 3.2 Global ID)

  11. AN
    September 20th, 2017

    3.1. Format

    The Local IPv6 addresses are created using a pseudo-randomly
    allocated global ID. They have the following format:

    | 7 bits |1| 40 bits | 16 bits | 64 bits |
    +——–+-+————+———–+—————————-+
    | Prefix |L| Global ID | Subnet ID | Interface ID |
    +——–+-+————+———–+—————————-+

    Where:

    Prefix FC00::/7 prefix to identify Local IPv6 unicast
    addresses.

    L Set to 1 if the prefix is locally assigned.
    Set to 0 may be defined in the future. See
    Section 3.2 for additional information.

    Global ID 40-bit global identifier used to create a
    globally unique prefix. See Section 3.2 for
    additional information.

    Subnet ID 16-bit Subnet ID is an identifier of a subnet
    within the site.

    Interface ID 64-bit Interface ID as defined in [ADDARCH].

  12. Mo
    October 6th, 2017

    Can anyone provide me with the latest dump valid

    Mahamedwarsame1 AT GMAIL DoT COM

    Thanks

  13. Riley
    December 18th, 2017

    Passed, if you go the exam study the 552q dumps.

  14. raptor
    January 29th, 2018

    what about question 10??

  15. cthelite
    February 26th, 2018

    Q9: The answer is A, but as picky as Cisco is about wording, I’m surprised no one has commented about it. “must be configured” implies a manual configuration is necessary. Of course that’s not so, I don’t HAVE to manually configure it. If I do nothing but enable IPv6 on the interface it will be automatically generated. So a better answer is “will be present” on all IPv6 interfaces, which encompasses manual configuration or automatic.

    None of the other answers are close to true, by virtue of elimination A must be correct, but I’m fearful about Cisco’s wording, so I’m very careful to understand the full scope of their questions!

  16. Anonymous
    March 9th, 2018

    Question 10?

  17. Anonymous
    March 9th, 2018

    Q10:
    Which tunneling mechanism embeds an IPv4 address within an IPv6 address?
    A. Teredo
    B. 6to4
    C. 4to6
    D. GRE E. ISATAP

    Answer C.

    A. Teredo – similar to 6to4 (connectivity by encapsulating IPv6 datagram packets within IPv4 User Datagram Protocol) (UDP)
    B. 6to4 -IPv6 traffic can be carried over IPv4 GRE tunnels. Overlay tunneling encapsulates IPv6 packets in IPv4 packets for delivery across an IPv4 infrastructure
    C. 4to6 – tunnel connecting IPv4 isolated sites on the IPv6 network is called an IPv4 over IPv6 tunnel
    D. GRE E. ISATAP – is a managed technology for providing IPv6 on an IPv4 network. It emulates IPv6 connectivity on the IPv4 infrastructure. IPv6 Router Discovery usually uses multicast. This isn’t possible on an infrastructure based on IPv6-over-IPv4 tunnels, so ISATAP solves that in a different way. An ISATAP router is provided on the network and its IPv4 address is made known to the ISATAP hosts (usually using the hostname isatap. in DNS). The ISATAP hosts then can use that address to set up their IPv6 connectivity.

  18. cthelite
    March 9th, 2018

    About Q10:

    The last contributor is incorrect. I don’t think there is such an animal as “4to6”. But “6to4” concatenates 2002::/16 with the IPv4 address embedded. The address format would be:

    2002:(32 bit IPv4 site address in Hex):(16 bit network number in Hex)::/64

    So the answer is B.

  19. Q4
    April 7th, 2018

    Q4. Which header field is new on IPv6?
    A. Version
    B. Hop Limit – Correct
    C. Flow Label – Correct
    D. Traffic Class

    The question ask for 1 answer, but in fact, there are 2 correct answers(B,D).
    Pretty sure the question asks for 2 answers, judging by the options given.
    Please review Q4.

  20. Q4
    April 7th, 2018

    Q4. Which header field is new on IPv6?
    A. Version
    B. Hop Limit – Correct
    C. Flow Label – Correct
    D. Traffic Class

    The question ask for 1 answer, but in fact, there are 2 correct answers(B,C).
    Pretty sure the question asks for 2 answers, judging by the options given.
    Please review Q4.

  21. cthelite
    April 8th, 2018

    Q1: B) fc00 and D) fd00 are correct.

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