A. The maximum number of times a double colon can replace a 16-bit segment that consists of all zeroes is two.

Transcription

1 What are two rules for compacting IPv6 addresses? (Choose two.) A. The maximum number of times a double colon can replace a 16-bit segment that consists of all zeroes is two. B. The leading zeroes in any 16-bit segment do not have to be written. C. Every 16-bit segment that consists of all zeroes can be represented with a single colon. D. The trailing zeroes in any 16-bit segment do not have to be written. E. Any single, continuous string of one or more 16-bit segments that consists of all zeroes can be represented with a double colon. F. Two zeroes in the middle of any 16-bit segment do not have to be written. Answer: B, E 1) IPv6 addresses often contain consecutive hexadecimal fields of zeros. To simplify address entry, you can use two colons (::) to represent the consecutive fields of zeros when typing the IPv6 address. Example address may be written as: 2001:db8:85a3:0:0:8a2e:370:7334 Example address can be further simplified: 2001:db8:85a3::8a2e:370:7334 2) Leading zeroes in a group may be omitted. Thus, the example address: 2001:0db8:85a3:0000:0000:8a2e:0370:7334 may be written as: 2001:db8:85a3:0:0:8a2e:370:

2 What is the difference between the IPv6 addresses ::/0 and ::/128? A. ::/0 is the unspecified address, and ::/128 is the multicast address. B. ::/0 is the unicast address, and ::/128 is the anycast address. C. ::/0 is the unicast address, and ::/128 is the multicast address. D. ::/0 is the anycast address, and ::/128 is the multicast address. E. ::/0 is the default route, and ::/128 is the unspecified address. F. ::/0 is the anycast address, and ::/128 is the default address. Answer: E Unspecified address ::/128 - The address with all zero bits is called the unspecified address (corresponding to /32 in IPv4). This address must never be assigned to an interface and is to be used only in software before the application has learned its host's source address appropriate for a pending connection. Routers must not forward packets with the unspecified address. Applications may be listening on one or more specific interfaces for incoming connections, which are shown in listings of active internet connections by a specific IP address (and a port number, separated by a colon). When the unspecified address is shown it means that an application is listening for incoming connections on all available interfaces. Default route ::/0 - The default unicast route address (corresponding to /0 in IPv4). More on: Link

3 Refer to the output. What IOS command produces this output? Routing Process "ospfv3 1" with ID Is is an autonomous system boundry router Redistributing External Routes from, static SPF schedule delay 5 secs, Hold time between two SPF's 10 secs Minimum LSA interval 5 secs, Minimum LSA arrival 1 secs LSA group pacing timer 240 secs Interface flood pacing timer 33 msecs Retransmission pacing timer 66 msecs Number of external LSA 1. Checksum Sum 0x218D Number of areas in this router is 1. 1 normal 0 stub 0 nssa Area 1 Number of interfaces om this area is 2 SPF algorithm executed 9 times Number of LSA 15. Checksum Sum 0x67581 Number of DCbitless LSA 0 Number of indication LSA 0 Number pf DoNotAge LSA 0 Flood list length 0 A. show ip ospf B. show ip ospf interface C. show ipv6 ospf interface D. show ipv6 ospf Answer: D show ipv6 ospf [process-id][area-id] command displays general information about IPv6 OSPF process

4 Using the rules for IPv6 addressing, how can the address 2031:0000:240F:0000:0000:09C0:123A:121B be rewritten? A. 2031:0:240F::09C0:123A:121B B. 2031::240F::09C0:123A:121B C. 2031::240F:9C0::123A:121B D. 2031::240F:::09C0:123A:121B Answer: A B and C are not correct because we can't use double colons (::) twice. You can use it only once in any address because if two double colons areplaced in the same address, there will be no way to identify the size of each block of 0s. D is not correct because we can't use triple colons (:::) in IPv6 presentation. Remember the following techniques to shorten an IPv6 address: - Omit leading 0s in the address field, so :0000 can be compressed to just :0 and :0d02 can be compressed to :d02 (but :1d00 can not be compressed to :1d) - Use double colons (::), but just once, to represent a contiguous block of 0s, so 2001:0d02:0000:0000:0014:0000:0000:0095 can be compressed to 2001:0d02::14:0:0:95 or 2001:0d02:0:0:14::

5 Refer to the partial configurations in the exhibit. What address is utilized for DR and BDR identification on Router1? Router1#show run **** output omitted **** interface serial1/1 ipv6 address 2001:410:FFFF:1::64/64 ipv6 ospf 100 area 0 interface serial2/0 ipv6 address 3FFF:B00:FFFF:1::2/64 ipv6 ospf 100 area 0 ipv6 router ospf router-id A. the serial 1/1 address B. the serial 2/0 address C. a randomly generated internal address D. the configured router-id address Answer: D The point of this question is DR and BDR election of OSPFv3. OSPF test the title of the DR and BDR election. DR and BDR election there are two standards: 1. Interface priority, the default is Router-id: manually specify> Highest loopback interface> Highest active IP address. Here there is no configured no priority, it is the default, and manually is specified the Router-id: , so with Routerid specified in the election router becomes the DR or BDR. The selection of DR and BDR is the same between OSPFv2 and OSPFv

6 Refer to the exhibit. What is required to complete the IPv6 routing configurations shown? Router1# interface S1/1 ipv6 address 2001:410:FFFF:1::1/64 ipv6 ospf 100 area 0 interface S2/0 ipv6 address 3FFF:B00:FFFF:1::2/64 ipv6 ospf 100 area 0 ipv6 router ospf router-id Router2# interface S3/0 ipv6 address 3FFE"B00:FFFF:1::1/64 ipv6 ospf 100 area 0 ipv6 router ospf 100 router-id A. Interface authentication must be configured. B. The routing processes must be configured with an area ID. C. IP unicast routing must be enabled. D. IPv4 addresses must be applied to the interfaces. Answer: C Cisco IOS ipv6 unicast-routing global configuration command for IPv6 enables IPv6 routing and is required before any IPv6 routing protocol is configured

7 When implementing OSPFv3, which statement describes the configuration of OSPF areas? A. In interface configuration mode, the OSPFv3 area ID combination assigns interfaces to OSPFv3 areas. B. In router configuration mode, the network wildcard area ID combination assigns networks to OSPFv3 areas. C. In interface configuration mode, the IPv6 OSPF process area ID combination assigns interfaces to OSPFv3 areas. D. In router configuration mode, the IPv6 OSPF interface area ID combination assigns interfaces to OSPFv3 areas. Answer: C One difference between OSPFv2 and OSPFv3 configuration is the way that IPv6 networks that are part of the OSPFv3 network are identified. The network area command used in OSPFv2 is not used in OSPFv3. Rather, in OSPFv3, interfaces are directly configured to specify which IPv6 networks are part of the OSPFv3 network. OSPFv3 is enabled on each interface, using the ipv6 ospf process-id area area-id [instance instance-id] interface configuration command

8 Which statement is true about the implementation of IPv6 in an already existing IPv4 network? A. IPv6 can be routed using the same routing protocol versions as IPv4 B. A router routing for IPv6 and IPv4 must convert IPv4 packets to IPv6 packets to route them. C. IPv4 and IPv6 networks can be routed simultaneously. D. Only OSPF version 3 can be utilized for routing IPv4 and IPv6. Answer: C IPv4 and IPv6 networks can be routed simultaneously using dual-stack. - Dual-stack techniques - Hosts and network devices run both IPv4 and IPv6 at the same time. This technique is useful as a temporary transition, but it adds overhead and uses many resources. It is an integration method in which a node has connectivity to both an IPv4 and IPv6 network; the node has two protocol stacks. The two stacks can be on the same interface or on multiple interfaces. A dual-stack node chooses which stack to use based on the destination address; the node should prefer IPv6 when available. The dual-stack approach to IPv6 integration will be one of the most commonly used methods. Old IPv4-only applications will continue to work as before, while new and modified applications take advantage of both IP layers

9 Which two reductions are the correct reductions of the IPv6 address 2001:0d02:0000:0000:0014:0000:0000:0095? (Choose two.) A. 2001:d02::14::95 B. 2001:0d02:::0014:::0095 C. 2001:0d02:::0014:0:0:0095 D. 2001:d02::14:0:0:95 E. 2001:d02:0:0:14::95 F. FF::0014:0:0:0095 Answer: D, E 1) IPv6 addresses often contain consecutive hexadecimal fields of zeros. To simplify address entry, you can use two colons (::) to represent the consecutive fields of zeros when typing the IPv6 address. Example address may be written as: 2001:db8:85a3:0:0:8a2e:370:7334 Example address can be further simplified: 2001:db8:85a3::8a2e:370:7334 2) Leading zeroes in a group may be omitted. Thus, the example address: 2001:0db8:85a3:0000:0000:8a2e:0370:7334 may be written as: 2001:db8:85a3:0:0:8a2e:370:

10 Which statement is true about the command ipv6 ospf 1 area 0? A. It must be issued in router global configuration mode to enable the OSPF process for IPv6. B. It must be issued in interface configuration mode to enable the OSPF process for IPv6. C. It must be issued before the network command to enable the OSPF process for IPv6. D. It must be issued after the network command to enable the OSPF process for IPv6. Answer: B One difference between OSPFv2 and OSPFv3 configuration is the way that IPv6 networks that are part of the OSPFv3 network are identified. The network area command used in OSPFv2 is not used in OSPFv3. Rather, in OSPFv3, interfaces are directly configured to specify which IPv6 networks are part of the OSPFv3 network. OSPFv3 is enabled on each interface, using the ipv6 ospf process-id area area-id [instance instance-id] interface configuration command

11 Your company plans on migrating their network from IPv4 to IPv6 in the near future. Which three techniques can be used to transition from IPv4 to IPv6? (Select three) A. Dual stack B. NAT-PT C. Flow label D. Mobile IP E. 6to4 tunneling F. Anycast G. MBGP Answer: A, B, E A wide range of techniques are available for the period of transition between IPv4 and IPv6. These techniques can be grouped into the following three categories: - Dual-stack techniques - Hosts and network devices run both IPv4 and IPv6 at the same time. This technique is useful as a temporary transition, but it adds overhead and uses many resources. - Tunneling techniques - Isolated IPv6 networks are connected over an IPv4 infrastructure using tunnels. The edge devices are the only ones that need to be dual-stacked. Scalability may be an issue if many tunnels need to be created. - Translation techniques - A translation device converts IPv6 packets into IPv4 packets and vise versa, allowing IPv6-only devices to communicate with IPv4-only devices. Scalability may again be an issue because of the resources required on the translator device

12 Refer to the exhibit. Routers R1 and R2 are IPv6 BGP peers that have been configured to support a neighbor relationship over an IPv4 internetwork. Which three neighbor IP addresses are valid choices to use in the highlighted section of the exhibit? (Choose three.) R1#show running-config <output omitted> interface tunnel 0 tunnel source Ethernet0 tunnel mode ipv6 ip auto-tunnel interface ethernet 0 ip address ipv6 address 3000:2222::1/64 <output omitted> router bgp no synchronization no bgp default ipv4-unicast neighbor remote-as <output omitted> A. ::0A43:0002 B. 0A43:0002:: C. :: D ::

13 E. 0:0:0:0:0:0: F :0:0:0:0:0:0 Answer: A, C, E - Taking the portion 0A43:0002, first divide the address into 2 Tuple-groupings (2 Hex Characters) = 0A Step1 > Take 0A and multiply the first character 0 by 16 and the second character 0 by 1. Add the two decimal values together to get the IPv4 decimal value IE: (0*16) + ((A=10)*1) = 10 Step2 > Repeat the same process with 43, IE: (4*16) + (3*1) = 67 Step3 > Repeat the same process with 00, IE: (0*16) + (0*1) = 0 Step4 > Repeat the same process with 02, IE: (0*16) + (2*1) = 2 This will give you an IPv4 address of :: is representation of IPv4 address of :0:0:0:0:0: is representation of IPv4 address of More on: Link1; Link