4.1. Wireline Network Architecture

The private IPv4 host in this diagram can reach global IPv4 hosts via translation on both the CLAT and PLAT. On the other hand, the IPv6 host can reach other IPv6 hosts on the Internet directly without translation. This means that the Customer Premises Equipment (CPE) / CLAT can not only have the function of a CLAT but also the function of an IPv6 native router for native IPv6 traffic. In this diagram, the v4p host behind the CLAT has [RFC1918] addresses.

                             +------+
                             |  v6  |
                             | host |
                             +--+---+
                                |
                            .---+---.
                           /         \
                          /   IPv6    \
                         |  Internet   |
                          \           /
                           `----+----'
                                |
   +------+   |                 .---+---.                    .------.
   |  v6  +---+   +------+     /         \     +------+     /        \
   | host |   |   |      |    /   IPv6    \    |      |    /   IPv4   \
   +------+   +---+ CLAT +---+   Network   +---+ PLAT +---+  Internet  |
   +--------+ |   |      |    \           /    |      |    \           /
   | v4p/v6 +-+   +------+     `---------'     +------+     `----+----'
   |  host  | |                                                  |
   +--------+ |                                               +--+---+
   +------+   |                                               | v4g  |
   | v4p  +---+                                               | host |
   | host |   |                                               +------+
   +------+   |

      <- v4p -> XLAT <--------- v6 --------> XLAT <- v4g ->

 v6  : Global IPv6
 v4p : Private IPv4
 v4g : Global IPv4

Figure 1: Wireline Network Topology

4.1. Wireline Network Architecture​

4.1. Wireline Network Architecture