The IP address of the Relay, i.e. the router's IP address to write in the relayed request (giaddr field in the Bootp packet). When there are multiple IP interfaces on the same VLAN such that the router has multiple IP addresses on the VLAN, the user can configure which of these addresses to use when relaying requests arriving on this VLAN. This relay address is used by the server to determines the subnet from which the address shall be allocated. The special value 255.255.255.255 means DUPLICATE. In this case the Relay will duplicate each request arriving on this VLAN and send to the server multiple copies of the request, a copy for each of the router's IP addresses on that VLAN. The relay address in each copy of the request shall be the router's IP address (NOT 255.255.255.255). The special value 0.0.0.0 means that the router shall use the Default value (lowest IP address on the VLAN) for the relay address