Description
Exam Demo
300-410 CCNP Implementing Cisco IP Routing (ROUTE v2.0)
QUESTION 1
Automatic 6-to-4 tunnels exist between dual-stack routers (A, B, and C). One router has the IPv6 address, 2002:D030:6BC0:173C::26:37D0/48
Which of the following addresses is the IPv4 address of the router with the IPv6 address 2002:D030:6BC0:173C::26:37D0/48?
A. 10.176.15.131
B. 10.200.80.67
C. 208.48.107.192
D. 208.138.16.110
Correct Answer: C
Section: (none)
Explanation
Explanation/Reference:
Explanation:
The IPv4 address of the IPv6 router is 208.48.107.192. In an automatic 6-to-4 tunnel, IPv6 addresses have the 2002::/16 prefix. The 32-bit IPv4 address
of the IPv6 router is then embedded into the IPv6 address. The 32 bits of the IPv4 address is embedded in the second and third quartet of the IPv6
address. The second and third quarters in the IPv6 address correspond to D030:6BC0. The conversion of these hexadecimal digits into decimal is given
as follows:
The IPv6 router does not have 10.176.15.131 as its IPv4 address. The 10.176.15.131 address is the IPv4 equivalent of the second and third quarter
(05B0:0F81) in the source IPv6 address.
The other two IPv4 addresses are incorrect as they pertain to neither of the two IPv6 hosts.
Objective:
Network Principles
Sub-Objective:
Recognize proposed changes to the network
References:
Cisco IOS IPv6 Implementation Guide > Implementing Tunneling for IPv6
QUESTION 2
You have recently joined a company as the network administrator. You have been asked to complete the configuration on the border routers for an
automatic 6-to-4 tunnel between several IPv6 network domains. The commands that are currently configured on the routers are as follows:
ipv6 route tunnel
interface tunnel
ipv6 address
tunnel source
Which of the following additional commands is required to complete the configuration of automatic 6-to-4 tunnel on the border routers?
A. tunnel mode ipv6ip
B. tunnel mode ipv6ip 6to4
C. tunnel mode ipv6ip auto-tunnel
D. tunnel mode ipv6ip isatap
Correct Answer: B
Section: (none)
Explanation
Explanation/Reference:
Explanation:
The correct answer is to use the tunnel mode ipv6ip 6to4 command to complete the configuration of an automatic 6-to-4 tunnel. This command requires
the use of IPv6 unicast addresses that have the 2002::/16 prefix.
The types of tunneling mechanisms supported by IPv6 are:
Automatic 6-to-4 tunnel
ISATAP tunnel
Manually configured tunnel
GRE tunnel
Apart from using a tunneling mechanism, interoperability between IPv4 and IPv6 can be provided by using a dual-stack infrastructure or Network
Address Translation-Protocol Translation (NAT-PT). A dual-stack infrastructure allows you to use both IPv4 and IPv6 addresses on the same router/
host. NAT-PT is used to translate IPv4 addresses to IPv6 and vice versa.
The tunnel mode ipv6ip command should not be used to complete the configuration because this command specifies IPv6 as the passenger protocol
and creates a manually configured tunnel.
The tunnel mode ipv6ip auto-tunnel command is not required to enable automatic 6-to-4 tunneling on the border routers. This command creates an automatic IPv4-compatible IPv6 tunnel between the routers.
The tunnel mode ipv6ip isatap command should not be used because this command creates an ISATAP tunnel.
Objective:
Network Principles
Sub-Objective:
Recognize proposed changes to the network
References:
Cisco IOS IPv6 Configuration Guide; Implementing Tunneling for IPv6 > Configuring Manual IPv6 Tunnels
Cisco > Cisco IOS IPv6 Command Reference > tunnel mode ipv6ip
QUESTION 3
You have implemented IPv6 automatic 6-to-4 tunneling between three IPv6 subnets as shown in the network exhibit. (Click the Exhibit(s) button.)
You have used the following commands to implement the automatic 6-to-4 tunnel:
Your supervisor has assigned the task of verifying the automatic 6-to-4 tunnel to one of your colleagues. Your colleague runs the show running-config
command and finds that incorrect IPv6 addresses have been assigned to the tunnel interfaces of the routers.
Which of the following IPv6 addresses should be assigned to rectify the problem? (Choose two.)
A. 2002::c0a8:2d01/64 to the Fa0/1 interface of rtrA
B. 2002:c0a8:4b01::1/64 to the Fa0/1 interface of rtrB
C. 2002:c0a8:7d01::1/64 to the Fa0/1 interface of rtrC
D. 2002:c0a8:4b01::1/64 to the Fa0/1 interface of rtrA
Correct Answer: BC
Section: (none)
Explanation
Explanation/Reference:
Explanation:
The 2002:c0a8:4b01::1/64 and the 2002:c0a8:7d01::1/64 IPv6 addresses should be assigned to the Fa0/1 interfaces of rtrB and rtrC, respectively.
Automatic 6-to-4 tunnels embed the IPv4 address of the tunnel interfaces into the second and third quartets of the IPv6 address that has the 2002::/16
prefix.
To assign IPv6 addresses to the tunnel interfaces, perform the following steps:
1. Convert the IPv4 address of the tunnel interface into binary.
2. Convert the binary equivalent of the IPv4 address into hexadecimal (IPv6).
3. Append the hexadecimal equivalent to the 2002::/16 prefix to form the IPv6 prefix of the tunnel interface.
For the Fa0/1 interface of rtrB, its IPv4 address of 192.68.75.1 is equivalent to the IPv6 address c0a8:4b01. This address is then appended to the
2002::/16 prefix, resulting in 2002:c0a8:4b01::/48. The remaining host bits can be filled with zeros. Similarly, the IPv4 address of the Fa0/1 interface of
rtrC is converted to the IPv6 address 2002:c0a8:7d01::/48.
The 2002::c0a8:2d01/64 IPv6 address should not be assigned to the Fa0/1 interface of rtrA. The Fa0/1 interface of rtrA has the IPv4 address
192.168.45.1. The IPv6 equivalent of the IPv4 address, which is c0a8:2d01, should be embedded in the second and third quartets of the IPv6 address
instead of the seventh and eighth quartets. IPv4 addresses are embedded into the last 32 bits for ISATAP tunnels.
The 2002:c0a8:4b01::1/64 IPv6 addresses should not be assigned to the Fa0/1 interface of rtrA. This IPv6 address is the equivalent of the IPv4 address
192.168.75.1, which is the address of the Fa0/2 interface of rtrB and not rtrA. Therefore, this IPv6 address should be assigned to the Fa0/1 interface of
rtrB.
Objective:
Network Principles
Sub-Objective:
Recognize proposed changes to the network
References:
Cisco Press > Articles > Cisco Certification > CCNP > CCNP Self-Study: Advanced IP Addressing
Cisco Press > Articles > Network Technology > General Networking > Cisco Self-Study: Implementing Cisco IPv6 Networks (IPV6)
Cisco > Support > Technology Support > IP > IP Version 6 (IPV6) > Configure > Configuration Examples and Technotes > IPv6 Tunnel Through an IPv4
Network
Cisco IOS IPv6 Implementation Guide, Release 15.2M&T > Implementing Tunneling for IPv6
QUESTION 4
An automatic IPv4-compatible IPv6 tunnel exists between two IPv6 networks. The two IPv6 networks belong to different BGP autonomous systems
(AS). The tunnel source has the IPv4 address 172.168.111.65/24 and the tunnel destination has the IPv4 address 172.168.222.80/24.
Which of the following statements is TRUE about the tunnel source and tunnel destination IPv6 addresses? (Choose two.)
A. the IPv6 address of the tunnel source is 172.168.111.65::
B. the IPv6 address of the tunnel source is ::172.168.111.65
C. the IPv6 address of the tunnel destination is 172.168.222.80::
D. the IPv6 address of the tunnel destination is ::172.168.222.80
Correct Answer: BD
Explanation
Explanation/Reference:
Explanation:
The IPv6 address of the tunnel source is ::172.168.111.65 and the IPv6 address of the tunnel destination is ::172.168.222.80. These two addresses are
IPv4-compatible IPv6 addresses, which are addresses that contain the IPv4 addresses of the tunnel source and destination.
In automatic IPv4-compatible IPv6 tunnel, the IPv4 addresses of the tunnel source and the tunnel destination are used to determine their IPv6
addresses. The IPv4 addresses of the tunnel source/destination are embedded into the least significant 32 bits of an all-zero unicast IPv6 address. The
resultant IPv6 address has zeros in the most significant 96 bits and the IPv4 address of the tunnel source/destination in the remaining 32 bits.
In this case, the source of an automatic IPv4-compatible IPv6 tunnel has the IPv6 address 0:0:0:0:0:0:172.168.111.65, abbreviated as ::2.168.111.65.
You can also convert this address into pure hexadecimal format, which would be ACA8:6F41.
Any of the following three addresses could be used to identify the BGP neighbor at 172.168.11.65:
0:0:0:0:0:0:172.168.111.65
::172.168.111.65
::ACA8:6F41
Similarly, the tunnel destination has the IPv6 address 0:0:0:0:0:0:172.168.222.80 (abbreviated as ::172.168.222.80). The hexadecimal form of the IPv6
address of the tunnel destination is ::ACA8:DE50.
Any of the following three addresses could be used to identify the BGP neighbor at 172.168.222.80:
0:0:0:0:0:0:172.168.222.80
::172.168.222.80
::ACA8:DE50
The other two options state incorrect IPv6 addresses of the tunnel source and the tunnel destination. Both options specify an IPv6 address that has the
IPv4 address of the tunnel source/destination in the most significant 32 bits and zeros in the least significant 96 bits.
Objective:
Network Principles
Sub-Objective:
Recognize proposed changes to the network
References:
Home > Support > Technology Support > IP > IP Version 6 (IPv6) > Configure > Configuration Examples and Technotes > IPv6 Tunnel Through an IPv4
Network > Configure > Configurations (Automatic IPv4-Compatible Mode)
Cisco IOS IPv6 Implementation Guide > Implementing Tunneling for IPv6
Cisco > Support > Technology Support > IP > IP Version 6 (IPv6) > Technology Information > Technology White Paper > IPv6 Deployment Strategies >
Selecting a Deployment Strategy > Deploying IPv6 Over IPv4 Tunnels > Automatic IPv4-Compatible Tunnel
QUESTION 5
Your company has implemented IPv6 addresses and routing on every host, server, and router. Recently, your company acquired another company that
has an IPv4 addressing scheme for its entire network. The acquired company’s network does not have any support for IPv6. You need to devise a
method so that the IPv6 hosts in your company can seamlessly communicate with the IPv4 hosts of the acquired company’s network. You do not want
to install any additional routers, and you want minimum configuration changes on the networks.
Which of the following is the best method to allow communication between the IPv4 and IPv6 hosts?
A. Embedding IPv6 packets into IPv4 packets
B. Translating IPv4 addresses to and from IPv6 addresses
C. Configuring IPv6 on the hosts and routers in the IPv4 network
D. ConfiguringIPv4 on the hosts and routers in the IPv6 network
Correct Answer: B
Section: (none)
Explanation
Explanation/Reference:
Explanation:
Translating IPv4 addresses to and from IPv6 addresses is the best method to allow communication between the IPv4 and IPv6 hosts. This translation of
IPv4 and IPv6 addresses is known as Network Address Translation-Protocol Translation (NAT-PT). NAT-PT is a technique available for deploying IPv6
and IPv4 addresses in a unified network. With NAT-PT, the network requires fewer modifications and software for the IPv4 and IPv6 hosts. Additionally,
it provides easy and quick interoperability between the IPv4 and IPv6 hosts.
NAT-PT is configured on one of the routers on the border of the IPv4 and IPv6 networks. Whenever an IPv4 packet intended for a host in the IPv6
network is received by the NAT-PT router, the router applies NAT-PT on the packet and translates all the headers in the IPv4 headers. In addition, it
translates the IPv4 source and destination addresses to IPv6 source and destination addresses. The IPv6 packet is then set by the NAT-PT router to the
intended IPv6 host. The NAT-PT router performs the reverse translation when an IPv6 host sends a packet to an IPv4 host.
Embedding IPv6 packets into IPv4 packets is not the best method to allow communication between the IPv4 and IPv6 hosts. When IPv6 packets are
embedded inside IPv4 packets, the process is referred to as tunneling. Tunneling is appropriate when two IPv6 networks are separated by an IPv4
network. When an IPv6 host of one network sends an IPv6 packet destined for a host on the other IPv6 network, an IPv4 tunnel is created between the
two IPv6 networks. The IPv6 packet is then embedded into an IPv4 packet that traverses through the IPv4 tunnel to reach the intended IPv6 host, where
the embedded packet is extracted by the recipient. In this scenario, a single IPv6 network is available; hence, a tunnel cannot be formed.
Configuring IPv6 on the hosts and routers in the IPv4 network, or configuring IPv4 on the hosts and routers in the IPv6 network, are not the best
methods to allow communication between the IPv4 and IPv6 hosts. Each of these two methods is cumbersome and not the most efficient for providing
interoperability between IPv4 and IPv6 in this case. Furthermore, the IPv4 hosts on the acquired company’s network do not support IPv6 as stated.
Objective:
Network Principles
Sub-Objective:
Recognize proposed changes to the network
References:
Cisco NAT Configuration Guide, Release 15M&T > NAT-PT for IPv6
