Retired Document

Important: This sample code may not represent best practices for current development. The project may use deprecated symbols and illustrate technologies and techniques that are no longer recommended.

PortMapper

Last Revision:	Version 1.0, 2008-07-25 Demonstrates Bonjour's NAT port-mapping API, and provides a higher-level Objective-C interface to it.
Build Requirements:	Xcode 3.0
Runtime Requirements:	Mac OS X 10.5

Bonjour (in Mac OS X 10.5 or later) provides a "port-mapping" facility, which allows a computer behind a Network Address Translator (NAT), such as a typical home router, to request a public TCP or UDP port number that can accept connections from outside. This allows the client to join peer-to-peer networks, or to provide a publicly-available service such as a Web server.

In 10.5 this facility is only available via the low-level <dnssd.h> header, and as such, using it requires familiarity with POSIX networking APIs (socket descriptors, sockaddrs, etc.) It also has no formal documentation, although there are extensive comments in the header file.

This sample code demonstrates how to use the API. It provides a complete Objective-C wrapper class that can be used as-is in Cocoa applications; or the innards of the class can be taken as snippets to use in other contexts.