(IMSI) and Mobile Station International Subscriber Directory Number (MSISDN) analysis, or transparently switching the PDN Connection to a different APN (using triggers from Policy and Charging Control (PCC) or AAA infrastructure). Dedicated IPv6 APN and a New Subscription A completely new non-overlapping IPv6 or dual-stack enabled APN is created and provisioned into the network. Subscribers and their UEs can be provisioned to the new APN on an opt-in basis. Since activating the new APN requires active participation from the subscriber side, there is a strong chance that the subscriber actually knows what he or she is doing. This approach works specifically for trialing purposes, but does not scale to large subscriber populations. Dedicated APNs allow IPv6 rollouts where the existing IPv4-only deployment remains completely untouched and new IPv6 features are rolled out possibly using more recent platforms. This can also work out well with new subscribers. IPv6 Enabled APN and Re-provisioning an Old Subscription In situations where an operator has an existing IPv4-only APN, but gradually wants to move subscribers to IPv6, an overlapping (name wise) IPv6-only or dual-stack APN is created and provisioned into the network. For simplicity, it makes sense to configure it into the same Gateway GPRS Support Nodes (GGSNs/PGWs) where the legacy IPv4-only APN is configured and hence save trouble on DNS configurations. If the network supports dual-stack - that is Release-9 or better for GPRS or Release-8 or better for EPS - then existing subscription profiles in HLRs or HSSs are updated to Deploying IPv6 in 3GPP Networks PDP or PDN Type IPv4v6. Otherwise, if the network does not support PDP or PDN Type IPv4v6, then an IPv6-only APN with the same name as the IPv4-only APN is provisioned into the subscription profiles. The provisioning may need to be done on an opt-in basis, when subscribers switch to a new mobile device or even as a mass re-provisioning in HLRs/HSSs. Mass provisioning always has the danger that some old UEs mi