On 12/3/2013 12:55 AM, Pedro Roque Marques wrote: > Is the fundamental IP behavior that you are referring to the TTL decrement > between two addresses on the same "subnet" ? > I believe you are wrong: to my knowledge proxy ARP is compliant with Host and > Router requirement RFCs.
For IPv4, RFC1812 says that all 1's "limited broadcast" (255.255.255.255) MUST NOT be forwarded. RFC2644 updates that RFC to say that even subnet-directed broadcasts MUST NOT be forwarded (as configured by default). So by default, a router would never forward the broadcast for which the proxy ARP would be an appropriate response. Which would mean that the proxy would work only if already populated at the router; there would be no means to forward the initial request if the cache were empty. So proxy ARP would work if manually configured, but would be unreliable if automatically populated if used on a router that spans two groups of hosts on the same subnet. Joe
