Ipv6 Questions

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    Question A- 1. Which of the following is the most likely organization from which anenterprise could obtain an administrative assignment of a block of IPv6 global unicast IPaddresses?a. An ISPb. ICANNc. An RIR

    d. Global unicast addresses are not administratively assigned by an outsideorganisation.

    Answer: A.One method for IPv6 global unicast address assignment is that ICANN(Internet Corporation for Assigned Network Numbers) allocates large address blocks toRIRs (Regional Internet Registry), RIRs assign smaller address blocks to ISPs (InternetService Provider), and ISPs assign even smaller address blocks to their customers.

    Question A- 2. Which of the following is the shortest valid abbreviation forFE80:0000:0000:0100:0000:0000:0000:0123?a. FE80::100::123

    b. FE8::1::123c. FE80::100:0:0:0:123:4567d. FE80:0:0:100::123

    Answer D.Inside a quartet, any leading 0s can be omitted, and one sequence of 1 ormore quartets of all 0s can be replaced with double colons (::). The correct answerreplaces the longer 3-quartet sequence of 0s with ::.

    Question A- 3 . Which of the following answers lists a multicastIPv6 address?a. 2000::1:1234:5678:9ABCb. FD80::1:1234:5678:9ABCc. FE80::1:1234:5678:9ABCd. FF80::1:1234:5678:9ABC

    Answer D.Global unicast addresses begin with 2000::/3, meaning that the first 3 bits match the valuein hex 2000.Similarly, unique local addresses match FD00::/8, and link local addresses matchFE80::/10 (values that begin with FE8, FE9, FEA, and FED hex).Multicast IPv6 addresses begin with FF00::/8, meaning that the first 2 hex digits areF.

    Question A- 4. Which of the following answers list either a protocol or function that canbe used by a host to dynamically learn its own IPv6 address?a. Stateful DHCPb. Stateless DHCPc. Stateless autoconfigurationd. Neighbor Discovery Protocol

    Answer: A and C. IPv6 supports stateful DHCP, which works similarly to IPv4s DHCPprotocol to dynamically assign the entire IP address. Stateless autoconfiguration alsoallows the assignment by finding the prefix from some nearby router and calculating the

    interface ID using the EUI-64 format.

    Question A- 5. Which of the following help allow an IPv6 host to learn the IP address

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    of a default gatewayon its subnet?a. Stateful DHCPb. Stateless RSc. Stateless autoconfigurationd. Neighbor Discovery Protocol

    Answer A and D.Stateless autoconfiguration only helps a host learn and form its own IPaddress, but it does not help the host learn a default gateway. Stateless RS is not a validterm or feature. Neighbor Discovery Protocol (NDP) is used for several purposes,including the same purpose as ARP in IPv4, and for learning configuration parameters likea default gateway IP address

    Question A- 6. Which of the following are routing protocols that support IPv6?a. RIPngb. RIP-2c. OSPFv2

    d. OSPFv3e. OSPFv4

    Answer A and D. OSPFv3, RIPng, EIGRP for IPv6, and MP-BGP4 all support IPv6.(Memory Hint: RIPng could also be regarded as RIP version 3!)

    Question A- 7. In the following configuration, this routers Fa0/0 interface has a MACaddress of 4444.4444.4444. Which of the following IPv6 addresses will the interface use?ipv6 unicast-routingipv6 router rip tag1interface FastEthernet0/0ipv6 address 3456::1/64

    a. 3456::C444:44FF:FE44:4444b. 3456::4444:44FF:FE44:4444c. 3456::1d. FE80::1e. FE80::6444:44FF:FE44:4444f. FE80::4444:4444:4444

    Answer C and E. The configuration explicitly assigns the 3456::1 IP address. The

    interface also forms the EUI-64 interface ID

    (6444:44FF:FE44:4444), adding it to FE80::/64, to form the link local IP address.

    Question A- 8. In the configuration text in the previous question, RIP was not workingon interface Fa0/0. Which of the following configuration commands would enable RIP onFa0/0?a. network 3456::/64b. network 3456::/16c. network 3456::1/128d. ipv6 rip enable

    e. ipv6 rip tag1 enable

    Answer E. RIPng configuration does not use a network command. Instead, the ipv6 rip

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    command is configured on the interface, listing the same tag as on the ipv6 router ripcommand, and the enable keyword.

    Question A- 9. Which of the following IPv4-to-IPv6 transition methods allows an IPv4-only host to communicate with an IPv6-only host?a. Dual-stack

    b. 6to4 tunnelingc. ISATAP tunnelingd. NAT-PT

    Answer D. Network Address TranslationProtocol Translation (NAT-PT) translatesbetween IPv4 and IPv6, and vice versa. The two tunneling methods allow IPv6 hosts tocommunicate with other IPv6 hosts, sending the packets through an IPv4 network. Dual-stack allows a host or router to concurrently support both protocols.[MY NOTE: NAT-PT is the only way an IPv4-only host can communicate with an IPv6-onlyhost. The other translation methods need the two protocols to work together with eachother.]

    (B) IPv6 Questions in www.9tut.com websiteThe www.9tut.comwebsite has a large number of CCNA exam questions (andSimulations, Simlets, Testlets etc) including 8 questions on IPv6. Seehttp://www.9tut.com/ccna-ipv6The following are some of these questions:

    Question B- 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 Leading zeros in IPv6 are optional so that 05C7 equals 5C7 and 0000equals 0. Therefore D is not correct.

    Question B- 5. Which three of the following are IPv6 transition mechanisms? (Choose

    three)

    A 6to4 tunnelingB GRE tunnelingC ISATAP tunnelingD Teredo tunnelingE VPN tunnelingF PPP tunneling

    Answer: A C D

    Below is a summary of IPv6 transition technologies:

    6 to 4 tunneling: This mechanism allows IPv6 sites to communicate with each other overthe IPv4 network without explicit tunnel setup. The main advantage of this technology isthat it requires no end-node reconfiguration and minimal router configuration but it is not

    http://www.9tut.com/http://www.9tut.com/http://www.9tut.com/ccna-ipv6http://www.9tut.com/http://www.9tut.com/ccna-ipv6http://www.9tut.com/
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    intended as a permanent solution.

    ISATAP tunneling(Intra-Site Automatic Tunnel Addressing Protocol): is a mechanism fortransmitting IPv6 packets over IPv4 network. The word automatic means that once anISATAP 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 CCNAso we shouldnt choose it (there are 4 types of IPv6 transition mechanisms mentioned inCCNA; they are: manual, 6-to-4, Teredo and ISATAP).

    [MY NOTE: For the CCNA exam, be sure that you can recognize the NAMES of the 3main tunneling types i.e. 6 to 4, ISATAPand Teredo ]

    Question B- 6. Which two descriptions are correct about characteristics of IPv6unicast 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

    Below is the list of common kinds of IPv6 addresses:

    Loopback address ::1

    Link-local addressFE80::/10

    Unique-localaddress

    FD00::/8

    Global address2000::/3

    Multicast addressFF00::/8

    [My Note: The 9tut.com answer actually has the Site-local addressprefix FEC0::/10inplace of the Unique-local address prefix FD00::/8 above. However Site-local addressesare now obsolete and have been replaced by Unique-local. ]

    Question B- 7.Select the valid IPv6 addresses. (Choose all apply)A ::192:168:0:1B 2002:c0a8:101::42C 2003:dead:beef:4dad:23:46:bb:101D ::E 2000::F 2001:3452:4952:2837::

    Answer: A B C D F

    Answers A and B are correct because A is the short form of 0:0:0:0:192:168:0:1 and B is

    the short form of 2002:c0a8:0101:0:0:0:0:0042.

    Answer C is correct because it is the normal IPv6 address.

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    Answer D is correct because :: is named the unspecified address and is typically usedin the source field of a datagram that is sent by a device that seeks to have its IP addressconfigured.

    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 aggregatableglobalunicastaddress.The 2000:: (in particular, 2000::/3) is just a prefix and is not a validIPv6 address.

    The entire global-unicast IPv6 address range is from 2000::/128 to3FFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF/128, resulting in a total usable space of over42,535,295,865,117,307,932,921,825,928,971,000,000 addresses, which is only 1/8th ofthe entire IPv6 address space!

    (C) IPv6 Questions by Chris Bryant

    Chris Bryant has six practice IPv6 questions on his website athttp://www.thebryantadvantage.com/CCNACertificationPracticeExamIPVersion6.htm

    His question 3 is related to the last question aboveQuestion C- 3:What address type is indicated by the first 96 bits being set to zero?Answer: That's an IPv4-compatible address.MY NOTE: Question 7 of the 9tut.com questions asks you to select valid IP v6 addressesand lists ::192:168:0:1 as one of them. Note the double colon :: at the beginning. Thisrepresents 96 bits set to zero leaving 32 bits for the IPv4 address which is incorporatedinto the IPv6 address.

    Question C- 6.Where will you find IPv6 addresses beginning with 2002 and carrying a /48prefix?

    A. 6to4 tunnel edge routers

    B. loopback interfaces

    C. 6to4 tunnel access routers

    D. Any link-layer master router

    E. Any site-local DR

    Answer A: 6to4 tunnel edge routers - the IPv6 routers that are communicating with eachother through the IPv4 cloud - carry an IPv6 address beginning with 2002, followed bytheir IPv4 address expressed in hex. They carry a /48 prefix.

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    (D) IPv6 Questions by Anthony Sequeira

    www.stormwindlive.comQuestion D- 1.Name three benefits of IPv6. Choose 3.a. Decreased reliance on multicastb. Elimination of broadcast behavior

    c. Enhanced DHCP usaged. Increased security featurese. IP address autoconfigurationAnswer: b, d, e

    Question D- 2.Which two statements regarding a link-local address are true? Choose 2.a. A link-local address is manually configured when neededb. A link-local address begins FE80c. A link-local address is assigned by the ISATAP tunnel processd. A link-local address is based upon an existing Layer 2 address

    Answer: b, d

    Question D- 3. What is the loopback address used in IPv6? Choose 2.a. 0:0:0:0:0:0:0:1b. 1:1:1:1:1:1:1:1c. 1::d. ::1Answer: a, d

    Question D- 4. Which of the following is NOTa feature of Anycast addressing in IPv6?a. Same IPv6 address assigned to multiple nodesb. Routing protocol makes the nearest determinationc. Supports many future potential applicationsd. Provides an any-to-many communication modelAnswer: d

    (E) from book "CCNA Practice Questions" - Chapter 8

    http://my.safaribooksonline.com/book/certification/ccna/9780768682427

    (The book "CCNA Practice Questions" byJeremy CCIE No. 11727 Cioara is published by

    Pearson Certification. Selections from it are available free - including the IPv6 questionsand answers.)Question E- 4. Which of the following are invalid IPv6 communication types? (Choosetwo.)A .UnicastB. MulticastC. BroadcastD. AnycastE. Cryptocast

    Answer: C, E. IPv6 uses three types of communication: Unicast (one-to-one), Multicast(one-to-many), and Anycast (one-to-closest). Answer C is incorrect because the conceptof Broadcast messaging is tied with the IPv4 protocol and is no longer valid in IPv6.Answer E is incorrect because there is no such thing as Cryptocast messaging.

    http://my.safaribooksonline.com/book/certification/ccna/9780768682427http://my.safaribooksonline.com/book/certification/ccna/9780768682427
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    Question E- 5. Which of the following are valid IPv6 addresses? (Choose three.)A. 2001:0db8:0000:0000:0000:0000:1428:57abB. 2001:0db8::1428:57abC. 2001::1685:2123::1428:57abD. 2001:99:ab:1:99:2:1:9

    E. 2001:1428:57ab:1685:2123:1428:57abAnswer: A, B, D.An IPv6 address consists of eight sets that can be four hexadecimalcharacters each. Consecutive sets of zeros can be abbreviated with a double colon (::),but this can only be used once in each IP address. Leading zeros can also be dropped.Based on these rules, addresses from the question can be described as:

    2001:0db8:0000:0000:0000:0000:1428:57ab (Valid, eight sets)2001:0db8::1428:57ab (Valid, same address as above with abbreviation)2001::1685:2123::1428:57ab (Invalid use of double colon)2001:99:ab:1:99:2:1:9 (Valid, dropped leading zeros)2001:1428:57ab:1685:2123: 1428:57ab (Invalid, only seven sets)

    QuestionE- 18. In IPv6, Internet-valid addresses are known by what name?A. PrivateB. PublicC. UniqueD. UnspecifiedE. Global

    Answer: E.The Internet-valid addresses are considered global addresses in IPv6. Theyare specified to begin with 2000::/3. Answer A is incorrect because private addresses arefor use in a private network, as it currently happens in IPv4 addressing. Answer B isincorrect because global addresses have replaced public addresses. Answers C and D donot apply directly to IPv6 addressing.

    Question E- 19. In IPv6, a ___________ address is used to communicate with hosts onthe directly attached network and will never forward beyond the first router hop.A. GlobalB. PrivateC. Link localD. Private restrictedE. Auto-generated

    Answer: C.Link-local addressing is a new concept when moving from IPv4 to IPv6. Link-local addresses are used to communicate directly on a link. This is used forcommunication such as establishing OSPF neighbor relationships or sending RIP routes.Answer A is incorrect because global addresses can access the Internet directly. Answer Bis incorrect because private IPv6 addresses can route through an organization. Theaddresses shown in answers D and E do not exist in the IPv6 environment.

    Question E- 20. Which of the following commands could you use to assign an IPv6address to your router?

    A .Router(config-if)#ip address fe01:3112:abcd::0001 255.255.255.0

    B .Router(config-if)#ip address fe01:3112:abcd::0001/48C .Router(config-if)#ip address 6 fe01:3112:abcd::0001 255.255.255.0D. Router(config-if)#ip address 6 fe01:3112:abcd::0001/48

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    E. Router(config-if)#ipv6 address fe01:3112:abcd::0001 255.255.255.0F. Router(config-if)#ipv6 address fe01:3112:abcd::0001/48

    Answer: F.IPv6 addresses are assigned using the ipv6 address command. In IPv6, thereis no decimal version of the subnet mask; all subnet masks are written in bit-notation.Answers A, C, and E are incorrect because they use the decimal version of the subnet

    mask. Answers B and D are incorrect because they use the incorrect command.

    Question E- 21 Which of the following commands could you use to start a RIPng processon your router?

    A. Router(config)#router RIPngB. Router(config)#ipv6 router rip RIPTagNo1C. Router(config)#routerv6 RIPD. Router(config)#ripv6

    Answer B. The exact syntax to enable the RIPng (RIP for IPv6) routing protocol is ipv6router rip . The tag can be anything from a number to a name; in this question, thetag was RIPTagNo1. This tag must be used when enabling RIP on an interface-by-interface basis. Answers A, C, and D will produce invalid syntax messages.

    Question E-30. Which of the following commands enables the IPv6 protocol on a router?A. Router(config)#ipv6 unicast-routingB. Router(config)#ipv6 enableC. Router(config)#enable ipv6D. Router(config)#ipv6E. Router(config)#router ipv6

    Answer: A.To enable the IPv6 protocol, use the command ipv6 unicast-routing fromglobal configuration mode. All other answers produce an invalid syntax or incompletecommand message.

    (F) Miscellaneous

    The following are two questions from the Cisco CCNA Discovery courseQuestion F-1 Refer to the following commandRouterX (config-if) IPv6 address 2001:DB8:2222:7272::72/64Which statement is true?

    Answer: The complete IPv6 address is manually specified for the interface.[My Note: This is a normal Global Unicast IPv6 address with a network prefix of 64 bits. Infull it would be:2001:0DB8:2222:7272:0000:0000:0000:0072/64 ]

    Question F-2 What are two ways that some networks can use IPv6 addresesand still communicate over the Internet with their other networks that use IPv4

    (choose two)?

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    The answersare:

    Enable tunnelingto allow IPv6 packets to be encapsulated and travel over IPv4

    networks AND

    Upgrade the IOS image on the IPv6 edge routers to an image that can translate

    IPv6 packets to IPv4 packets.