I think this describes the confusion here. You are looking for a default IP address for the device so that users can connect to it for configuring it? In IPv4 there is usually a default RFC 1918 address that will do just this function in order to enable configuration. So would it meet your needs if we used something like ::192:168:0:1 for the default address if it is used via the Ethernet or wireless (802.11x) port?You are right in the analysis of the confusion. However, I think we should move away from such things as well know IP addresses and use some form of service discovery protocol instead.
Alain,The problem with addressing this problem with a service discovery protocol is that it will not meet the requirement of what to do when the router is the only service and is in need of initial configuration. In the past Cisco mandated that the console port was the way to do this while others have gone for a direct connect USB, but in a wireless situation there is no physical port to connect to while configuring the CPE. So unless you want to replace a "well known IP address" with a "well known ULA" then we need to find another solution. Or are you proposing that we make the discovery protocol enable a "find and configure CPE/router" option? If so I have a problem with the security implications of such a wide open configuration requirement. Eric