System Administration Guide: IP Services

Interaction With Applications

Even on a node that has been upgraded to IPv6, the use of IPv6 is dependent on the applications. An application might not use a networking API that asks the name service for IPv6 addresses. The application might use an API (such as sockets) that requires changes in the application. Also, the provider of the API, such as an implementation of the class might not support IPv6 addresses. In either situation, the node only sends and receives IPv4 packets like an IPv4 node would.

The following names have become standard terminology within the Internet community: