Yet Another Traffic Shape Question:


WAN --- m0n0wall -- LAN

LAN is 192.168.1.0/255

In m0n0wall create two subnetting LAN alias:
LANfast   -  ip from 192.168.1.1 to 192.168.1.126 (192.168.1.0/25)
LANslow - ip from 192.168.1.129 to 192.168.1.254 (192.168.1.0/25)


WAN is an ADSL with x kbps download and y kbps upload

I want to be sure that:
- every clients have the maximum band for in/out  (*)
- clients of subnet LANfast have AT LEAST  x/2 (download) and y/2 
(upload) of band (in worse situation)

(*) suppose that only 1 client of subnet LANslow is connect than this 
client have the full ADSL band

How to setup traffic shaper for this?

thanks in advance.
v.