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CFNetwork Concepts

CFNetwork is a low-level, high-performance framework that gives you the ability to have detailed control over the protocol stack. It is an extension to BSD sockets, the standard socket abstraction API that provides objects to simplify tasks such as communicating with FTP and HTTP servers or resolving DNS hosts. CFNetwork is based, both physically and theoretically, on BSD sockets.

Just as CFNetwork relies on BSD sockets, there are a number of Cocoa classes that rely on CFNetwork. NSURL is one such class used for communicating with servers using standard Internet protocols. In addition, the Web Kit is a set of Cocoa classes to display web content in windows. Both of these classes are very high level and implement most of the details of the networking protocols by themselves. Thus, the structure of the software layers looks like the image in Figure 1-1.

Contents:

When to Use CFNetwork
CFNetwork Infrastructure
CFNetwork API Concepts

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