Most distributions come along with boot disks that work for all common types of PC hardware. This means that the kernel on those disks has all sorts of drivers configured in that you will never need, but which waste precious system memory because parts of the kernel cannot be swapped out. Therefore, you will generally roll your own kernel, including only those drivers you actually need or want.
When running a system, you should be familiar with building a kernel. The basics of this are explained in Matt Welsh's ``Installation and Getting Started'' Guide, which is also part of the Documentation Project's series. In this section, we will therefore discuss only those configuration options that affect networking.
When running make config, you will first be asked general configurations, for instance whether you want kernel math emulation or not, etc. One of these asks you whether you want TCP/IP networking support. You must answer this with y to get a kernel capable of networking.