> and this statement makes me sad and angry Your MAC and/or IP address should not identify you, and never should have been used as an identifier. It's the ide

> and this statement makes me sad and angry Your MAC and/or IP address should not identify you, and never should have been used as an identifier. It's the identity of a communication endpoint. If the OSI model is about making the core of the network stupid and fast, which has proven benefits of scalability and/or extensibility, then identity/authentication is not the network layer's job and never was. If a protocol assumes all hosts on a subnet are trustworthy (ARP/DHCP for example), it's an upper-level protocol design failure, not really having to do with transport (TCP/UDP)/network (IP) layers.