5.2. Wireless 3GPP Network Applicability

5.2. Wireless 3GPP Network Applicability

At the time of writing, in April 2013, the vast majority of mobile networks are compliant to Pre-Release 9 3GPP standards. In Pre-Release 9 3GPP networks, Global System for Mobile Communications (GSM) and Universal Mobile Telecommunications System (UMTS) networks must signal and support both IPv4 and IPv6 Packet Data Protocol (PDP) attachments to access IPv4 and IPv6 network destinations [RFC6459]. Since there are two PDPs required to support two address families, this is double the number of PDPs required to support the status quo of one address family, which is IPv4.

For the cases of connecting to an IPv4 literal or IPv4 socket that require IPv4 connectivity, the CLAT function on the UE provides a private IPv4 address and IPv4 default route on the host for the applications to reference and bind to. Connections sourced from the IPv4 interface are immediately routed to the CLAT function and passed to the IPv6-only mobile network, destined for the PLAT. In summary, the UE performs the CLAT function that does a stateless translation [RFC6145], but only when required by an IPv4-only scenario such as IPv4 literals or IPv4-only sockets. The mobile network has a PLAT that does stateful translation [RFC6146].

464XLAT works with today's existing systems as much as possible. 464XLAT is compatible with existing solutions for network-based deep packet inspection like 3GPP standardized Policy and Charging Control (PCC) [TS.23203].