Multicast routing method and apparatus for routing multicast packet

Abstract

A communications apparatus for converting an IPv4 multicast packet transmit from an IPv4 terminal into an IPv6 multicast packet and transmitting the converted IPv6 multicast packet to one of a plurality of IPv6 networks. The communications apparatus has information indicating to which IPv6 network the IPv4 multicast packet to undergo conversion processing is to be transmitted. The communications apparatus then converts the received IPv4 multicast packet into an IPv6 multicast packet and transmits the converted IPv6 multicast packet to an IPv6 network where it is required to be sent.

1 - 21 . (canceled)  
     
     
         22 . A device for routing a multicast packet between at least one first device using IPv4 as a communication protocol and at least one second device using IPv6 as a communication protocol, the device comprising: 
 two or more interfaces connected via a network to either of the at least one first device or the at least one second device;    a memory unit for storing an interface of the two or more interfaces intended to route an IPv4 multicast packet transmitted from the one of the at least one first device;    a transmission/reception unit for routing the IPv4 multicast packet received from the one of the two or more interfaces to another of the two or more interfaces; and    a conversion unit for converting an IPv4 multicast address contained as a destination address in the received IPv4 multicast packet into an IPv6 multicast address and generating from the IPv4 multicast packet an IPv6 multicast packet containing the IPv6 multicast address as a destination address,    wherein the transmission/reception unit routes the IPv6 multicast packet to the interface connected to the at least one second device stored in the memory unit, and    wherein an IPv4 multicast route protocol and an IPv6 multicast route protocol are managed and the IPv4 multicast addresses and IPv6 multicast addresses are stored in a dynamically corresponding manner.    
     
     
         23 . A device according to  claim 22 , wherein, when the one of the two or more interfaces receives from one of the at least one second device a message requesting a transmission of the IPv6 multicast packet, the memory unit stores the interface that has received the message as the interface that is intended to route the IPv6 multicast packet.  
     
     
         24 . A device according to  claim 22 , wherein, when one of the two or more interfaces receives from one of the at least one second device an MLD Report message, the memory unit stores the interface that has received the message as the interface that is intended to route the IPv6 multicast packet.  
     
     
         25 . A device according to  claim 22 , further comprising: 
 a message generation unit for generating a query message for checking the presence of a device that is intended to receive the IPv6 multicast packet,    wherein the transmission/reception unit transmits the query message from one of the two or more interfaces which is connected with one of the at least one second device through a network.    
     
     
         26 . A device according to  claim 25 , wherein, when the one interface receives a reply message in response to the query message from the at least one second device, the memory unit stores the interface that has received the reply message as the interface that is intended to route the IPv6 multicast packet.  
     
     
         27 . A device according to  claim 22 , further comprising: 
 a message generation unit for generating an MLD Query message,    wherein the transmission/reception unit transmits the message from one of the two or more interfaces that is connected with one of the at least one second device through a network.    
     
     
         28 . A device according to  claim 27 , wherein, when the one interface receives an MLD Report message in response to the MLD Query message from the at least one second device, the memory unit stores the interface that has received the MLD Report message as the interface that is intended to route the IPv6 multicast packet.  
     
     
         29 . A device according to  claim 22 , further comprising: 
 a second memory unit for holding an IPv6 multicast address that is matched in advance with the IPv4 multicast address,    wherein the conversion unit converts the IPv4 multicast address into the IPv6 multicast address held in the second memory unit.    
     
     
         30 . A device for routing a multicast packet between at least one first device using IPv4 as a communication protocol and at least one second device using IPv6 as a communication protocol, the device comprising: 
 two or more interfaces connected via a network to one of the at least one first device or the at least one second device;    a memory unit for storing an interface of the two or more interfaces which is intended to route an IPv4 multicast packet transmitted from one of the at least one first device;    a transmission/reception unit for routing the IPv4 multicast packet received from one of the two or more interfaces to another of the two or more interfaces; and    a conversion unit for converting an IPv4 multicast address contained as a destination address in the received IPv4 multicast packet into an IPv6 multicast address, converting an IPv4 unicast address contained as a source address in the IPv4 multicast packet into an IPv6 unicast address, and generating from the IPv4 multicast packet an IPv6 multicast packet containing the IPv6 multicast address as a destination address and containing the IPv6 unicast address as a source address,    wherein the transmission/reception unit routes the IPv6 multicast packet to the interface connected to the at least one second device stored in the memory unit, and    wherein an IPv4 multicast route protocol and an IPv6 multicast route protocol are managed and the IPv4 multicast addresses and IPv6 multicast addresses are stored in a dynamically corresponding manner.    
     
     
         31 . A device for routing a multicast packet between at least one first device connected to an IPv4 network and at least one second device connected to an IPv6 network, the device comprising: 
 two or more interfaces connected via an IPv4 network or IPv6 network to one of the at least one first device or the at least one second device;    a memory unit for storing an interface of the two or more interfaces which is intended to receive an IPv4 multicast packet transmitted from the at least one first device and which is connected to the at least one first device or the at least one second device;    a transmission/reception unit for routing the IPv4 multicast packet received from one of the two or more interfaces to another interface; and    a conversion unit for converting an IPv4 multicast address contained as a destination address in the received IPv4 multicast packet into an IPv6 multicast address and generating from the IPv4 multicast packet an IPv6 multicast packet containing the IPv6 multicast address as a destination address,    wherein the transmission/reception unit routes the IPv6 multicast packet to the interface stored in the memory unit which is connected to the at least one second device, and    wherein an IPv4 multicast route protocol and an IPv6 multicast route protocol are managed and the IPv4 multicast addresses and IPv6 multicast addresses are stored in a dynamically corresponding manner.    
     
     
         32 . A device according to  claim 31 , wherein 
 the at least one first device or the at least one second device that receives the IPv4 multicast packet forms a multicast group, and    when one of the two or more interfaces receives from one of the at least one second device a message requesting to join the multicast group, the memory unit stores the interface that has received the message as an interface connected with a device belonging to the multicast group.    
     
     
         33 . A device according to  claim 31 , wherein 
 the at least one first device or the at least one second device that receives the IPv4 multicast packet forms a multicast group, and    when one of the two or more interfaces receives from one of the at least one second device an MLD Report message, the memory unit stores the interface that has received the message as an interface connected with a device belonging to the multicast group.