Network Address Translation Six to Four for Proxy Mobile Internet Protocol Version Six

• US 20120005372A1
• Filed: 06/28/2011
• Published: 01/05/2012
• Est. Priority Date: 07/02/2010
• Status: Active Grant

• Current Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Sarikaya, Behcet, Xia, Yangsong
• Granted Patent: US 9,210,735 B2
• Time in Patent Office: Days
• US Class Current: 709/245
• CPC Class Codes: H04L 61/251 between different IP versions
• CPC Class Codes: H04L 61/2553 Binding renewal aspects, e.g. using keep-alive messages
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04W 80/045 involving different protocol versions, e.g. MIPv4 and MIPv6
• CPC Class Codes: H04W 88/182 Network node acting on behalf of an other network entity, e.g. proxy

Abstract

An apparatus comprising a Local Mobility Anchor (LMA) configured to couple to a mobile node (MN), a network address translation (NAT) server, and an Internet Protocol (IP) version four (IPv4) only host and to associate an IP version six (IPv6) address for an interface with the MN with an IPv4 address for an interface with the IPv4 only host in a NAT state table entry, wherein the NAT state table entry is used to translate an IPv6 packet associated with the MN to an IPv4 packet associated with the IPv4 only host.

Claims

1. An apparatus comprising:

a Local Mobility Anchor (LMA) configured to couple to a mobile node (MN), a network address translation (NAT) server, and an Internet Protocol (IP) version four (IPv4) only host and to associate an IP version six (IPv6) address for an interface with the MN with an IPv4 address for an interface with the IPv4 only host in a NAT state table entry,

wherein the NAT state table entry is used to translate an IPv6 packet associated with the MN to an IPv4 packet associated with the IPv4 only host.

2. The apparatus of claim 1, wherein the NAT state table entry is also used to translate a unicast IPv4 packet associated with the IPv4 only host to a unicast IPv6 packet associated with the MN.

3. The apparatus of claim 1, wherein the NAT state table entry is linked to a binding cache entry (BCE) for the MN that maps an address of the MN to a care-of-address (CoA) associated with the MN, and wherein the BCE comprises an IPv6 only flag that is set.

4. The apparatus of claim 1, wherein the LMA and the NAT server are colocated on the same network component where the unicast IPv6 packet is translated to the unicast IPv4 packet.

5. The apparatus of claim 1, wherein the LMA and the NAT server are separated and located on different network components, and wherein the unicast IPv6 packet is translated to the unicast IPv4 packet at the NAT server.

6. The apparatus of claim 1, wherein the LMA maintains a prefix table for unicast communication that comprises an IPv6 prefix (Pref64) that is assigned to the NAT server by a domain name system (DNS) server.

7. The apparatus of claim 1, wherein the LMA is configured to handle the MN'"'"'s mobility based on Proxy Mobile IPv6 (PMIPv6) and forward both IPv6 and IPv4 packets between the MN and/or other MNs and one or more hosts.

8. The apparatus of claim 1, wherein the LMA is configured to support prefixes for multicast communication, and wherein the prefixes for multicast communication comprise at least one of an ASM_MPREFIX64 prefix value and a SSM_MPREFIX64 prefix value.

9. The apparatus of claim 1, wherein the LMA and the MN communicate via a mobile access gateway (MAG) that is configured to disable localized routing between the MN and another MAG by setting an EnableMAGLocalROuting flag to zero.

10. A network component comprising:

a receiver at a Local Mobility Anchor (LMA) configured to receive an Internet Protocol (IP) version four (IPv4) multicast data packet that comprises an IPv4 address from an IPv4 host;

a processor at the LMA configured to translate the IPv4 multicast data packet into an IP version six (IPv6) multicast data packet that comprises an IPv6 address based on the IPv4 address; and

a transmitter configured to send the IPv6 multicast data packet to a mobile access gateway (MAG) associated with a plurality of mobile nodes (MNs) that are subscribed to the IPv6 address.

11. The network component of claim 10, wherein the MAG duplicates and sends the IPv6 multicast data packet for each of the MNs.

12. The network component of claim 10, wherein the LMA sends an Internet Group Management Protocol (IGMP) join (IGMP Membership Report) message to the IPv4 host upon receiving a multicast listener discover (MLD) join (MLD Membership Report) message from one of the MNs to join a multicast group for the IPv4 host.

13. The network component of claim 10, wherein the IPv6 packet comprises an IPv6 address that includes an IPv6 prefix and the IPv4 address, and wherein the IPv6 prefix is an any source multicast (ASM) prefix or a source specific multicast (SSM) prefix.

14. The network component of claim 13, wherein the ASM prefix comprises an ASM MPREFIX64 prefix.

15. The network component of claim 13, wherein the SSM prefix comprises a SSM MPREFIX64 prefix.

16. The network component of claim 10, wherein the IPv6 packet comprises the IPv6 address, an IPv6 traffic class field that corresponds to a type of service field in the multicast data packet, an IPv6 next header that corresponds to an IPv4 protocol field in the multicast data packet, a hop limit field that corresponds to a time to live (TTL) field in the multicast data packet, and an IPv6 payload that corresponds to an IPv4 payload in the multicast data packet.

17. The network component of claim 10, wherein the multicast packet is an IPv4 fragment packet, and wherein the IPv6 packet comprises an IPv6 fragment header, a fragment header that corresponds to a fragmentation offset field in the multicast data packet, an IPv6 fragment header identification field that includes an about 16-bit identification field in the multicast data packet and about 32 additional higher order bits that are set to about zero, and a more fragment (MF) field that corresponds to a MF field in the multicast data packet.

18. The network component of claim 10, wherein the LMA supports SSM and Internet Group Management Protocol (IGMP) on an upstream interface of the LMA, and wherein the LMA sends an IGMP join message after receiving a multicast listener discovery (MLD) Join message from an IPv6-only MN to a next hop router that supports IGMP when the IPv6-only MN joins a source specific group (S,G).

19. The network component of claim 10, wherein the LMA supports SSM and Protocol Independent Multicast (PIM) on an upstream interface of the LMA, and wherein the LMA establishes a session with an upstream non-neighbor router to send a PIM Join message when a MN joins a source specific group (S,G).

20. The network component of claim 10, wherein the LMA sends a plurality of keepalive messages based on a determined keepalive interval to a network address translation (NAT) server instead of a MN to refresh a NAT state table entry that is associated with a binding cache entry (BCE) for the MN, wherein the keep alive messages are Internet Control Message Protocol (ICMP) Echo Request messages that each comprise a User Datagram Protocol (UDP) header and serve as outbound refresh messages for outgoing packets to the IPv4 only host.

21. The network component of claim 20, wherein the LMA receives a plurality of keepalive messages based on a determined time interval from the NAT server to refresh the BCE for the MN, wherein the keepalive messages are ICMP Echo Reply messages that serve as inbound refresh messages for incoming packets from the IPv4 only host.

22. The network component of claim 21, wherein the NAT state table entry comprises an IPv6 prefix (Pref64) that is assigned to the NAT server, an IPv6-only flag that is set, and the keepalive interval for keeping alive a communication session for the MN.

23. A network apparatus implemented method comprising:

receiving at a Local Mobility Anchor (LMA) an Internet Protocol (IP) version six (IPv6) packet from a mobile node (MN);

setting an IPv6-only flag in a binding cache entry (BCE) at the LMA for the MN that is not previously set if an IPv6 prefix in a destination address in the IPv6 packet is detected in a prefix mapping;

translating the IPv6 packet to an IPv4 packet using a network address translation (NAT) state table entry that matches a source address in the IPv6 packet; and

forwarding the IPv4 packet to an IPv4 only host associated with the destination address.

24. The network apparatus implemented method of claim 23, wherein the prefix mapping comprises a prefix table.

25. The network apparatus implemented method of claim 23 further comprising forwarding the IPv6 packet without translation if the IPv6 prefix is not found in the prefix table.

26. The network apparatus implemented method of claim 23 further comprising:

creating the NAT state table entry if the source address in the IPv6 packet is not found; and

linking the NAT state table entry to the BCE for the MN.