if '现在的项目要求我将网络部分作为模块加载,并测试两种情况下linux网络性能的差异' is u only topic, i can tell u that there is no difference whether net is linked into kernel or as a module and loaded into kernel. this is decided by linux kernel implementation. u can read the code about linux how to load module and add symbol table to system to know why. after loading a kernel, its symbol is treated as same as the one already in kernel. so there is no difference. this is also the great value of linux. load on demand.
for the linux router part. i am sorry that i do not have much knowledge on that part. my research direction is storage performance. so i know some about io and fs part only.
i will download a 2.5.6x kernel and try it when i have time. which option under network u needed?
i try the 2.5.68. but i do not think i can do that. i think that need modify the kernel source code and modify the makefile. i do not have so many time. i need code for my food. hehe