You are the network administrator for your company. You want to use both IPv6 and IPv4 applications in the
network. You also want to ensure that routers can route both IPv6 and IPv4 packets.
Which deployment model should be implemented to accomplish the task?

A.
IPv6 over IPv4 tunnels

B.
IPv6 over dedicated Wide Area Network (WAN) links

C.
Dual-Stack Backbones

D.
Protocol translation

Explanation:
A dual-stack backbone deployment model should be used to accomplish the task in this scenario. When
routers route both IPv6 and IPv4 packets, it is called dual stack routing or a dual-stack backbone.
The following deployment models are available for IPv4 to IPv6 migration:
IPv6 over IPv4 tunnels: IPv6 traffic is encapsulated into IPv4 packets. Then these packets are transferred
over an IPv4 WAN. This model eliminates the need to create separate circuits to connect to the IPv6
networks. This model increases protocol overhead because of the IPv6 headers and requires one end to be
capable of both protocols
Protocol translation: A translation method of allowing an IPv6 host to communicate with an IPv4 host. This is
accomplished with the help of Network Address Translation – Protocol Translation (NAT-PT) used to
configure translation between IPv6 and IPv4 hosts. NAT-PT allows communication between IPv6 hosts and
applications, and native IPv4 hosts and applications.
IPv6 over dedicated WAN links: A new deployment of IPv6 is created. In this model, IPv6 hierarchy,
addressing, and protocols are used by all nodes. However, this model involves cost for creating IPv6 WAN
circuits. This solution is not designed for LAN translation but rather translation over WAN links.
Dual-Stack Backbones: A hybrid model in which backbone routers have dual-stack functionality, which
enables them to route both IPv4 and IPv6 packets. It is suitable for an enterprise that uses both IPv4 and
IPv6 applications. Running IPv6 and IPv4 together in a network is known as dual-stack routing.
Objective:
Network Fundamentals
Sub-Objective:
Identify the appropriate IPv6 addressing scheme to satisfy addressing requirements in a LAN/WAN
environment

Cisco > Dual Stack Network
Cisco > Technology Support > IP > IPv6 > Configure > Configuration Examples and TechNotes > Tunneling
IPv6 through an IPv4 Network > Document ID: 25156