About the driver of 4 ports SWITCHER.

Sincerly Stranger:

I am a fresh embedded programmer.Now,I have a problem and it is too hard for me.Before now,our board has a network set which is a 4 ports SWITCHER.

But ,a new board was constructed at the last two days,and the 4 ports SWITCHER was replaced by a one port Interface.Maybe,call it as a NIC will be better.So,I have to write this to look for help.

Question:

How can I changed the driver of the 4 ports SWITCHER to one port NIC structure ?(or Which modules can I changed ?)

Now, I know file ecos.ecc has several optionable modules.

In the other hand,Dose DNS(for lookups),BOOTP(dynamic IP) and TFTP are needed by a SWITCHER ?

Too many thanks.