We have found no ASIC IP implementations that
hardwire in assumptions about specific IP address ranges. If you know
of any, please let us know, otherwise, let's let that strawman rest.
There's at least one. Marvell PresteriaCX (its either PresteriaCX or DX, forget which). It is in Juniper EX4500, among others.
Hardware-based bogon filter when L3 routing that cannot be disabled.
cheers,
lincoln.