Technical data

ServerIron ADX NAT64 Configuration Guide 29

53-1002444-02

Stateless NAT64 overview

DRAFT: BROCADE CONFIDENTIAL

FIGURE 8 IPv4 client to DNS64 server communication

3. The request packet is then sent to the NAT64 gateway using the IPv6 address obtained from

the DNS64 server as the destination IP (DIP) address (2001:db8:64::192.0.2.1.) and

2001:db8:80::80 as the source IP (SIP) address.

4. The NAT64 gateway strips away the initial portion of the IPv6 destination address leaving an

IPv4 destination address (192.0.2.1) for the resource.

5. The NAT64 gateway uses its mapping table to translate the IPv6 SIP (2001:db8:80::80) into

the IPv4 address that represents the IPv6 client to the IPv4 network (200.1.1.1).

The mapping table used for this translation is populated statically or dynamically (by way of a

real-time DNS query or prefetched DNS query). For more information, refer to “Populating the

NAT64 mapping table” on page 30.

6. When the IPv4 resource sends a return packet to the IPv6 client, the NAT64 gateway uses the

mapping table to translate the IPv4 DIP into the IPv6 address of the client: 2001:db8:80::80.

7. The NAT64 gateway concatenates the IPv6 prefix (2001:db8:64) to the IPv4 address of the

resource (192.0.2.1) to create a synthesized IPv6 address that represents the IPv4 resource to

the IPv6 network: 2001:db8:64::192.0.2.1.

The process occurs as shown in Figure 9.

DNS Server

IPv6 Client

IPv6

www.brocadetest.com

2001:db8:64::192.0.2.1