Computer networks with unique identification

A computer network is described in which the data-link layer address, e.g., MAC address, of the network cards of client nodes are used to uniquely identify the nodes in the provision of network to application layer services. A link layer aware router may determine the MAC address of a client node from a data packet transmitted by the client node, and determines the services to provide to the user, e.g., a proxy redirect of the packet, based on a database of client node MAC addresses to user attributes. By determining MAC addresses, the router can also identify unregistered MAC addresses, and can forward a HTTP request by an unregistered user to a remote configuration web page for registering the user or to a security warning web page. The router may also support Network Address Translation and Domain Name System services using the MAC addresses, with a fully qualified domain name, hostname or the like being assigned to the MAC addresses.