Cisco Cisco 2504 Wireless Controller Referencia técnica

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Cisco Wireless LAN Controller IPv6 Deployment Guide, CUWN Release 8.0
D r a f t   L a b e l — C i s c o   C o n f i d e n t i a l
Phase 1—Client IPv6 Support in WLC Release 7.2 to 7.6
end
IPv6 Client Mobility 
In order to deal with roaming IPv6 clients across controllers, the ICMPv6 messages such as NS, NA, RA, and RS must be 
dealt with specially to ensure that a client remains on the same Layer 3 network. The configuration for IPv6 mobility is 
the same as for IPv4 mobility and requires no separate software on the client side to achieve seamless roaming. The only 
required configuration is the controllers must be part of the same mobility group/domain.
The process of IPv6 client mobility across controllers is as follows:
1.
If both controllers have access to the same VLAN the client was originally on, the roam is simply a Layer 2 roaming 
event where the client record is copied to the new controller and no traffic is tunneled back to the anchor controller.
2.
If the second controller does not have access to the original VLAN the client was on, a Layer 3 roaming event will 
occur, meaning all traffic from the client must be tunneled via the mobility tunnel (Ethernet over IP) to the anchor 
controller. In a mixed deployment with Release 7.x and 8.x, Ethernet over IP is used. In pure 8.0 deployments, we 
support CAPWAP tunnel for IPv6 mobility tunnel.
a.
To ensure that the client retains its original IPv6 address, the Router Advertisements from the original VLAN are 
sent by the anchor controller to the foreign controller where they are delivered to the client using L2 Unicast from 
the AP. 
b.
When the roamed client goes to renew its address via DHCPv6 or generate a new address via SLAAC, the Router 
Solicitation, Neighbor Advertisement, and Neighbor Solicitation packets continue to be tunneled to the original 
VLAN so that the client receives an IPv6 address that is applicable to that VLAN.
Note: Mobility is based on VLAN information. It is not based on the IPv4 subnet or IPv6 prefix in use. This means that 
IPv6 client mobility is not supported on untagged VLANs.