Ipv6 Over Ipv4 Tunneling; Overview; Implementation; Tunnel Modes - HPE FlexNetwork 10500 Series Configuration Manual

IPv6 over IPv4 tunneling

Overview

Implementation

IPv6 over IPv4 tunneling enables isolated IPv6 networks to communicate, as shown in
NOTE:
The devices at both ends of an IPv6 over IPv4 tunnel must support the IPv4/IPv6 dual stack.
Figure 87 IPv6 over IPv4 tunnel
IPv6 header
IPv6 network
IPv6 host
The IPv6 over IPv4 tunnel processes packets by using the following steps:
1. A host in the IPv6 network sends an IPv6 packet to Device A at the tunnel source.
2. After Device A receives the IPv6 packet, it processes the packet as follows:
a. Searches the routing table to identify the outgoing interface for the IPv6 packet.
The outgoing interface is the tunnel interface, so Device A knows that the packet needs to
be forwarded through the tunnel.
b. Adds an IPv4 header to the IPv6 packet and forwards the packet through the physical
interface of the tunnel.
In the IPv4 header, the source IPv4 address is the IPv4 address of the tunnel source, and
the destination IPv4 address is the IPv4 address of the tunnel destination.
3. Upon receiving the packet, Device B de-encapsulates the packet.
4. If the destination address of the IPv6 packet is itself, Device B forwards it to the upper-layer
protocol. If it is not, Device B forwards it according to the routing table.

Tunnel modes

IPv6 over IPv4 tunnels include manually configured tunnels and automatic tunnels, depending on
how the IPv4 address of the tunnel destination is obtained.
•
Manually configured tunnel—The destination IPv4 address of the tunnel cannot be
automatically obtained from the destination IPv6 address of an IPv6 packet at the tunnel source.
It must be manually configured.
IPv4 header
IPv6 data
IPv6 over IPv4 tunnel
Device A
IPv6 header IPv6 data
IPv4 network
Device B
240
IPv6 header IPv6 data
IPv6 network
IPv6 host
Figure 87.