Patent ID: 7035261
Filing Date: 2006-04-25
Classification: H04L

Abstract:
1. A routing control method in a mixed environment of a network of a first type and a network of a second type, respectively defined by first and second address spaces, the first and second address spaces each having network-identifying and host-identifying portions, wherein the network of the first type provides routing control by referencing a subset of address bits of the network-identifying portion of the first address space, and the network of the second type provides routing control by referencing an entirety of address bits of the network-identifying portion of the second address space, comprising: assigning the network of the second type a virtual hierarchy number that corresponds to the subset of address bits of the network-identifying portion of the first address space and identifies the network of the second type as a network of the first type subordinate to a router for routing the packet to the network of the first type, attaching the virtual hierarchy number to a packet to be relayed at the router when the packet is to be relayed between the network of the second type and the network of the first type, performing routing control by the virtual hierarchy number within the network of the first type, and removing the virtual hierarchy number from the packet to be relayed at the router when the packet is to be relayed between the network of the first type and a network of the second type, wherein an address of the network of the second type is accommodated in an interface identification information block of an address format of the network of the first type, and the virtual hierarchy number is accommodated in a hierarchy information block of the address format of the network of the first type for said routing control within the network of the first type, each of one or more routers of the network of the first type comprises a first routing table that performs said routing control by using only the hierarchical information block as a key, and a second routing table that performs routing control by using the hierarchical information block and the interface identification information block as keys.