Patent ID: 7861292

Claim:
A method for processing a packet at a router of a first Internet Service Provider (ISP) network, comprising: determining whether a source address of the received packet is properly associated with a port on which the packet is received, wherein determining is based upon whether the source address of the received packet is within a valid range associated with the port on which the packet is received; when the source address of the received packet is determined to not be properly associated with the port on which the packet is received, marking the packet for forwarding in an unprivileged class of service; and when the source address of the received packet is determined to be properly associated with the port on which the packet is received, determining whether a destination address of the received packet is one of a predetermined one or more addresses; wherein the packet is marked for forwarding in a privileged class of service when the destination address of the received packet is one of the predetermined one or more addresses; wherein the packet is marked for forwarding in an unprivileged class of service when the destination address of the received packet is not one of the predetermined one or more addresses.