tal 65536 unique to a CPE. 3. It contains an IPv4 prefix. Bootstrapping In order for the MAP enabled devices to be able to do the algorithmic processing of the prefixes, a set of information has to be provisioned to these devices. Manual configuration does not scale and is highly error prone. In the case of CPEs, DHCPv6 is a natural method for MAP specific information distribution and provisioning [43]. A CPE would use DHCPv6 in the majority of cases anyway to bootstrap itself. The information delivered includes: transport mode (encapsulation or translation), used IPv6 and IPv4 prefixes, PSID related information, relay addresses, and SO on. From the 3GPP networks and deployments point of view, the dependency on DHCPv6 could be an issue. As we know, DHCPv6 is not a mandatory part of the 3GPP system architecture. Furthermore, since MAP is not even part of the recommended transition tool set for 3GPP networks, there is little hope, for example, for Non-Access Stratum (NAS) protocol support for bootstrapping the required provisioning information. Examples As we saw from Figure 5.12 the algorithmic generation of the IPv6 address used in MAP is not the most straightforward. Below we show an example how to build the address to Deploying IPv6 in 3GPP Networks length provisioned provisioned provisioned address port num p bits q bits suffix Port set ID for basic mapping rule Rule IPv6 prefix EA bits subnet ID Interface Identifier (IID) n bits o bits S bits 128-n-s-o bits (=64) End user IPv6 prefix provisioned p bits for forwarding mapping rule suffix IPv4 address address for translation mode default mapping rule provisioned (suffix can be up to 32 bits, i.e. full address) Figure 5.12 Basic mapping rule and forwarding mapping rule for both translation and encapsula- tion mode IPv6 address derivation. For the default mapping rule in translation mode the interface identifier needs to be modified. and from the Internet to a host behind a CPE. These examples are almost directly taken from the IETF draft [21]. A MAP enabled bord