As more clients are using IPv6, the operator must support both IPv4 and IPv6. Ideally providers want to drop support for the IPv4 network. However, doing so prevents clients from accessing IPv4 servers, which represents a significant portion of the internet. To solve this problem, most major network providers are implementing a DNS64/NAT64 transitional workflow.
In this typical flow, the client sends DNS queries to a DNS64 server, which requests IPv6 addresses from the DNS server. When an IPv6 address is found, it is passed back to the client immediately. However, when an IPv6 address is not found, the DNS64 server requests and IPv4 address. DNS64 server then synthesizes an IPv6 address by prefixing IPv4 address, and passes back to the client. In this regard the client always receives and IPv6 ready address.
Below is the sequence diagram showing the overall procedure
When the client sends a request to server, any IPv6 packets destined for synthesized addresses are automatically routed by the network through a NAT64 gateway. The gateway performs IPv4 to IPv6 translation for the response from the server.
References:
No comments:
Post a Comment