I'm managing the network of a small ISP and working on adding IPv6 to the network.
Subscribers connect to the ISP services by either PPPoE or L2TP dialers.
On the ISP side the edge router (Juniper E310 BRAS) is configured with local DHCP pool out of which a /48 is assigned to each subscriber.
This works great for client devices that uses IPv6DHCP with prefix delegation option to request a prefix.
However when the client does not have a CPE and uses his windows box to connect (by using Windows L2TP dialer) an IPv6 prefix is not assigned.
In packet captures we noticed that the windows client is sending DHCPv6 solicit messages requesting for absolute non temporary addresses (IA_NA).
This makes sense as the device is a host however it's not supported by the Juniper router.
We tried another option which is to send RA from the Juniper with a common /48 prefix for all subscribers.
In packet captures we are seeing the RA message with the prefix information, however the windows client does not assign itself with any global scope address.
I'm not sure if we are doing something wrong on the Juniper ERX, or should something be changed on the Win7 boxes.
Any help would be highly appreciated.
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