This is a group of attacks I'll mention in passing only. They have been fairly ``popular'' for a while. Tools such as teardrop and land targeted bugs in the IP network stack of several operating systems. By sending special network packets, they caused the victim computers to crash completely, resulting in a kernel oops, blue screen of death, etc, depending on the operating system.
Basically, this is just a variation of the ``crashing application'' problem described in the previous paragraphs. The difference being that operating system crashes are somewhat more spectacular than simple applications dumping core.
I won't go into the details of these attacks here. Some people find them a fascinating topic (probably the same set of people that watch pro wrestling shows on TV). However, writing IP network stacks is not really a very common occupation, so I think these issues are beyond the scope of this book.