enquiry on validation of dhcp offered addres

[ching]

I will look for other way to prevent routing intranet traffic to outside.

> Hang on ... you never said anything about that before !
>
> If all you are interested in is preventing routing certain traffic
> outside of your network then just apply a few firewall rules to block
> it. That too is nothing to do with DHCP.
>
This partially solve the problem as dropping internal traffic can result 
in a denial of service attack.