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Cisco SCE 8000 10GBE Software Configuration Guide
OL-30621-02
Chapter 7 Configuring Line Interfaces
Tunneling Protocols
Tunneling IPv6 Traffic
The following tunnels are supported for IPv6 traffic:
•
6to4 and 6rd
Tunneling can be done in two modes:
–
IPv6 mode—Traffic is handled as native IPv6-classified IPv6-over-IPv4 service. All the IPv6
flows work in a subscriber-less mode.
In the IPv6 mode, you can configure the IPv6 hash or the IPv4 hash. When the IPv6 hash is
configured, the IPv6 traffic is handled by the traffic processor card configured to handle the
IPv6 traffic based on the IPv6 hash. When the IPv4 hash is configured, the IPv6 traffic is
handled by the traffic processor card configured to handle the IPv6 traffic based on the IPv4 IP
hash.
–
IPv4 mode—Traffic is handled as IPv4-classified IPv6-over-IPv4 service. Traffic is accounted
for and enforced based on the IPv4 subscriber. Hashing is not significant.
•
DS-Lite
DS-Lite is a light-weight dual stack that is used when only public IPv6 addresses and private IPv4
addresses can be assigned. The extension header is supported on the DS-Lite tunnels.
When DS-Lite is enabled, the IPv6 traffic is handled as TCP/UDP by the traffic processor configured
to handle the IPv6 traffic. If DS-Lite is disabled, the IPv6 traffic is bypassed as non-TCP/UDP by
the traffic processor configured to handle the IPv6 traffic.
DS-Lite bundling is supported for FTP traffic. IPV6 addresses and L4 ports are used for binding FTP
control flows and FTP data flows. The FTP control flows are classified, and IPv6 addresses and L4
ports are used to create a binding context to bind the data flows to the control flow.
•
L2TP
Cisco SCE supports IPv6 over IPv4 L2TP tunnels. In L2TP IPv6 over IPv4 tunnels, the internal L3
header is IPv6 and the external L3 header is IPv4. The Cisco SCE uses internal IPv6 addresses for
tasks such as subscriber awareness, classification, load-balancing, congestion mangement.
Cisco SCE process IPv6 over IPv4 L2TP tunnels when L2TP skip is enabled.
The L2TP IPv6 over IPv4 is considered as tunneled traffic only in Generic Usage RDRs.
Some of the tunneling protocols can be configured in both modes, but some of the protocols work in
tunneled mode only. For example, the 6to4 tunneling protocol is supported in both the modes.
The following tunnels are not supported for IPv6 traffic:
•
GRE
•
VLAN
•
MPLS