© 2006 Cisco Systems, Inc. All rights reserved. BSCI v Implementing IPv6 Using IPv6 with IPv4

© 2006 Cisco Systems, Inc. All rights reserved. BSCI v IPv4-to-IPv6 Transition Transition richness means: –No fixed day to convert; no need to convert all at once. –Different transition mechanisms are available: Smooth integration of IPv4 and IPv6. Use of dual stack or 6to4 tunnels. –Different compatibility mechanisms: IPv4 and IPv6 nodes can communicate.

© 2006 Cisco Systems, Inc. All rights reserved. BSCI v Cisco IOS Software Is IPV6-Ready: Cisco IOS Dual Stack If both IPv4 and IPv6 are configured on an interface, this interface is dual-stacked.

© 2006 Cisco Systems, Inc. All rights reserved. BSCI v Dual stack is an integration method where a node has implementation and connectivity to both an IPv4 and IPv6 network. Dual Stack

© 2006 Cisco Systems, Inc. All rights reserved. BSCI v Cisco IOS Software Is IPv6-Ready: Overlay Tunnels Tunneling encapsulates the IPv6 packet in the IPv4 packet.

© 2006 Cisco Systems, Inc. All rights reserved. BSCI v Tunneling Tunneling is an integration method where an IPv6 packet is encapsulated within another protocol, such as IPv4. This method of encapsulation is IPv4 protocol 41: This method includes a 20-byte IPv4 header with no options and an IPv6 header and payload. This method is considered dual stacking.

© 2006 Cisco Systems, Inc. All rights reserved. BSCI v Isolated Dual-Stack Host Encapsulation can be done by edge routers between hosts or between a host and a router.

© 2006 Cisco Systems, Inc. All rights reserved. BSCI v Cisco IOS Software Is IPv6-Ready: Configured Tunnel Configured tunnels require: Dual-stack endpoints IPv4 and IPv6 addresses configured at each end

© 2006 Cisco Systems, Inc. All rights reserved. BSCI v Example: Cisco IOS Tunnel Configuration

© 2006 Cisco Systems, Inc. All rights reserved. BSCI v Cisco IOS Software Is IPv6-Ready: 6to4 Tunneling 6to4 Is an automatic tunnel method Gives a prefix to the attached IPv6 network

© 2006 Cisco Systems, Inc. All rights reserved. BSCI v NAT-Protocol Translation (NAT-PT) is a translation mechanism that sits between an IPv6 network and an IPv4 network. The job of the translator is to translate IPv6 packets into IPv4 packets and vice versa. TranslationNAT-PT

© 2006 Cisco Systems, Inc. All rights reserved. BSCI v Summary The two most common techniques to make the transition from IPv4 to IPv6 are dual stack and IPv6-to-IPv4 (6-to-4) tunnels. Tunneling IPv6 traffic over an IPv4 network requires one edge router to encapsulate the IPv6 packet inside an IPv4 packet and another router to decapsulate it. Transition methods from IPv4 to IPv6 include dual-stack operation, protocol translation, and 6to4 tunnels.

© 2006 Cisco Systems, Inc. All rights reserved. BSCI v