When having displaced the ISP-supplied DSL/ADSL/SDSL router at a premise using DHCP OPTIONS using a FreeBSD/Linux and ISC dhclient at many locations, and that i

When having displaced the ISP-supplied DSL/ADSL/SDSL router at a premise using DHCP OPTIONS using a FreeBSD/Linux and ISC dhclient at many locations, and that is the client-side of DHCP. And ISP likes to have their custom routers (which is a DHCP client, BTW) respond in all sorts of funky ISP-specific DHCP key/value sets. Not just smoke. FIRE!