CN-3-4-1 - Handoff - After the return routability procedure
Host
HA----------R2----------R1----------R0
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|---- |----MN' |----MN |----CN(NUT)
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Home Link Link2 Link1 Link0
(Foreign) (Foreign)
Link0 3ffe:501:ffff:100::/64 Link1 3ffe:501:ffff:101::/64 Foreign Link Link2 3ffe:501:ffff:102::/64 Foreign Link 2 Home Link 3ffe:501:ffff:104::/64 Home Link CN(NUT) 3ffe:501:ffff:100::X
Auto Configuration (InterfaceID)MN(in Link1) 3ffe:501:ffff:101::Y
Increased in each test (InterfaceID)MN care-of address MN'(MN in Link2) 3ffe:501:ffff:102::Y
Increased in each test (InterfaceID)MN care-of address 2 MN(in Home Link) 3ffe:501:ffff:104::Y
Increased in each test (InterfaceID)MN home address R0(Link0) 3ffe:501:ffff:100::1 R1(Link1) 3ffe:501:ffff:101::1 R2(Link2) 3ffe:501:ffff:102::1 HA(Home Link) 3ffe:501:ffff:104::1
Reboot NUT (reboot.rmt)
MN MN' R1 R2 HA R0 CN(NUT)
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| | | | | |------>| 1.RA
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| | | | | |------>| 2.NS
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| | | |<------| 3.NA
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|------------------------------->|-------------->| 4.Echo Request
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|<-------------------------------|<--------------| 5.Echo Reply
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|----------------------------------------------->| 6.Echo Request(Home Address option)
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|<-----------------------------------------------| 7.BE(Status=1)
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|----------------------------------------------->| 8.CoTI
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|------------------------------->|-------------->| 9.HoTI
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|<-----------------------------------------------| 10.CoT
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|<-------------------------------|<--------------| 11.HoT
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|----------------------------------------------->| 12.BU
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|<-----------------------------------------------| 13.BA
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|----------------------------------------------->| 14.Echo Request(Home Address option)
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|<-----------------------------------------------| 15.Echo Reply(Type2 Routing Header)
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| |-------------------------------------->| 16.CoTI
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| |---------------------->|-------------->| 17.HoTI
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| |<--------------------------------------| 18.CoT
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| |<----------------------|<--------------| 19.HoT
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| |-------------------------------------->| 20.BU(Source Address=CoA2)
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| |<--------------------------------------| 21.BA(Destination Address=CoA2) (*1)
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| |---------------------->|-------------->| 22.Echo Request
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| |<--------------------------------------| 23.Echo Reply(Type2 Routing Header, Destination Address=CoA2) (*2)
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| |-------------------------------------->| 24.Echo Request(Home Address option, Source Address=CoA2)
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| |<--------------------------------------| 25.Echo Reply(Type2 Routing Header, Destination Address=CoA2) (*3)
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1. Send Router Advertisement. 2. Send Neighbor Solicitation. 3. Receive Neighbor Advertisement. 4. Send ICMP Echo Request. 5. Receive ICMP Echo Reply. 6. Send ICMP Echo Request(Home Address option). 7. Receive Binding Error(Status=1). 8. Send Care-of Test Init. 9. Send Home Test Init. 10. Receive Care-of Test. 11. Receive Home Test. 12. Send Binding Update. 13. Receive Binding Acknowledgement. 14. Send ICMP Echo Request(Home Address option). 15. Receive ICMP Echo Reply(Type2 Routing HeaderADestination Address=CoA1). 16. Send Care-of Test Init. 17. Send Home Test Init. 18. Receive Care-of Test. 19. Receive Home Test. 20. Send Binding Update(Source Address=CoA2). 21. Receive Binding Acknowledgement(Destination Address=CoA2). 22. Send ICMP Echo Request. 23. Receive ICMP Echo Reply(Type2 Routing Header, Destination Address=CoA2). 24. Send ICMP Echo Request(Home Address option, Source Address=CoA2). 25. Receive ICMP Echo Reply(Type2 Routing Header, Destination Address=CoA2).
Packet Format 20. Binding Update 21. Binding Acknowledgement 22. ICMP Echo Request 23. ICMP Echo Reply(Type2 Routing Header) 24. ICMP_Echo Request(Home Address option) 25. ICMP Echo Reply(Type2 Routing Header)
(*1) MN' receives Binding Acknowledgement. - The Destination Address is set to the Source Address of the Binding Update (MN care-of address 2). - Type 2 Routing Header is included. - The Home Address field of Type 2 Routing Header is set to MN home address.
(*2) MN' receives ICMP Echo Reply. (Binding Cache entry is created.) - The Destination Address is set to the Source Address of the Binding Update (MN care-of address 2). - Type 2 Routing Header is included. - The Home Address field of Type 2 Routing Header is set to MN home address.
(*3) MN' receives ICMP Echo Reply. (Binding Cache entry is created.) - The Destination Address is set to the Source Address of the Binding Update (MN care-of address 2). - Type 2 Routing Header is included. - The Home Address field of Type 2 Routing Header is set to MN home address.
(draft-ietf-mobileip-ipv6-24.txt)
9.5.1 Receiving Binding Updates
o If the Lifetime specified in the Binding Update is nonzero and the
specified care-of address is not equal to the home address for the
binding, then this is a request to cache a binding for the home
address. If the Home Registration (H) bit is set in the Binding
Update, the Binding Update is processed according to the procedure
specified in Section 10.3.1; otherwise, it is processed according
to the procedure specified in Section 9.5.2.
9.5.2 Requests to Cache a Binding
In this case, the receiving node SHOULD create a new entry in its Binding Cache for this home address, or update its existing Binding Cache entry for this home address, if such an entry already exists. The lifetime for the Binding Cache entry is initialized from the Lifetime field specified in the Binding Update, although this lifetime MAY be reduced by the node caching the binding; the lifetime for the Binding Cache entry MUST NOT be greater than the Lifetime value specified in the Binding Update. Any Binding Cache entry MUST be deleted after the expiration of its lifetime.
9.5.4 Sending Binding Acknowledgements
If the Source Address field of the IPv6 header that carried the Binding Update does not contain a unicast address, the Binding Acknowledgement MUST NOT be sent, and the Binding Update packet MUST be silently discarded. Otherwise, the acknowledgement MUST be sent to the Source Address. Unlike the treatment of regular packets, this addressing procedure does not use information from the Binding Cache. However, a routing header is needed in some cases. If the Source Address is the home address of the mobile node, i.e., the Binding Update did not contain a Home Address destination option, then the Binding Acknowledgement MUST be sent to that address, and the routing header MUST NOT be used. Otherwise, the Binding Acknowledgement MUST be sent using a type 2 routing header which contains the mobile node's home address.