464XLAT Overview

You can configure the MX Series router as an 464XLAT Provider-Side Translator (PLAT). 464XLAT provides a simple and scalable technique for an IPv4 client with a private address to connect to an IPv4 host over an IPv6 network. 464XLAT only supports IPv4 in the client-server model, so it does not support IPv4 peer-to-peer communication or inbound IPv4 connections.

XLAT464 provides the advantages of not having to maintain an IPv4 network for this IPv4 traffic and not having to assign additional public IPv4 addresses.

A customer-side translator (CLAT), which is not a Juniper Networks product, translates the IPv4 packet to IPv6 by embedding the IPv4 source and destination addresses in IPv6 prefixes, and sends the packet over an IPv6 network to the PLAT. The PLAT translates the packet to IPv4, and sends the packet to the IPv4 host over an IPv4 network (see Figure 1).

Figure 1: 464XLAT Wireline Flow

The CLAT uses a unique source IPv6 prefix for each end user, and translates the IPv4 source address to an IPv6 address by embedding it in the IPv6 /96prefix. In Figure 1, the CLAT source IPv6 prefix is 2001:db8:aaaa::/96, and the IPv4 source address 192.168.1.2 is translated to 2001:db8:aaaa::192.168.1.2. The CLAT translates the IPv4 destination address to IPv6 by embedding it in the IPv6 prefix of the PLAT (MX Series router). In Figure 1, the PLAT destination IPv6 prefix is 2001:db8:bbbb::/96, so the CLAT translates the IPv4 destination address 198.51.100.1 to 2001:db8:bbbb::198.51.100.

The PLAT translates the IPv6 source address to a public IPv4 address, and translates the IPv6 destination address to a public IPv4 address by removing the PLAT prefix.

The CLAT can reside on the end user mobile device in an IPv6-only mobile network, allowing mobile network providers to roll out IPv6 for their users and support IPv4-only applications on mobile devices (see Figure 2).

Figure 2: 464XLAT Wireless Flow

464XLAT supports the following:

• Address pooling and endpoint independent mapping (see Address Pooling and Endpoint Independent Mapping for Port Translation).

• Secured port block allocation (see Secured Port Block Allocation for Port Translation