SCCM 2012 SP1 OSD with Non-Microsoft DHCP "BT Diamond"

Our environment:

               SCCM 2012 SP1, Non-Microsoft DHCP "BT Diamond", we need to deploy images for clients in different subnet

We had Configure OSD, Create Image, and Task sequence.

But when try to use PXE for supported client, we get PXE-E32 TFTP open timeout,

My questions:

1- we must have Windows DCHP to make OSD working.

2- how to resolve PXE-E32 TFTP open timeout