OS X and iOS Kernel Programming

Networking in the I/O Kit

The IONetworkingFamily of classes represents the bottom part of the kernel network stack. As previously discussed, the I/O Kit is the preferred layer for implementing drivers for hardware-based network devices. The class hierarchy of the IONetworkingFamily is shown in Figure 13-4.

Figure 13-4. The IONetworkingFamily class hierachy

The family may look quite expansive, but many of the classes are auxiliary helper classes, and some, we do not need to worry about at all because they are only used internally in the family. The key classes in the family are the IONetworkController and IONetworkInterface. The former is used ...