Failover computing

1. Failover for Multiple Mobile
Routers in a NEMO
draft-ryu-nemo-mr-failover-02.txt IETF Monami6 WG
Jiho Ryu 2006. 11. 10.
Nakjung Choi
Eunkyong Paik
Taekyung Kwon
Chulhyun Park
Presenter:
Seungjae Lee
SNU MMLab
sjlee@mmlab.snu.ac.kr

2. Outline
 Problem statement
 Failover for Multiple Mobile Routers
 Implementation Report
 Summary
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3. Problem statement - 1
 Multihomed NEMO
 Multiple MRs, Multiple HAs, Multiple mobile
network prefixes (MNPs)
HA2
HA1 Internet
MR1 MR2
MNP1 MNP2
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4. Problem statement - 2
 When MR1 fails,
 Mobile nodes under MR1
 Sessions will be broken.
 Automatically reconfigure their addresses.
 Ingress-filtered if MR2~HA2 is used.
 Our solution:
 MR surrogates its peer MR, which is failed
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5. Failover for Multiple MRs - 1
 Extends Multiple CoA Registration
 Wakikawa et al.
 Assumption
 MRs can hear their RA each other
 MR can maintain peer MR entry through
authentication, and vice versa
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6. Failover for Multiple MRs - 2
 Peer MR registration
 An MR hears RA from another MR
 MR2 is registered as a peer MR of MR1 and vise versa
 Failover
 Explicit failure notification message or no RA for a while
 A peer MR surrogates failed MR
 Broadcasts RA for failed MR
 Establishes an alternative tunnel to HA of failed MR
 Recovery
 Recovery notification message
 Failover state ends
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7. Failover for Multiple MRs - 3
 Expected Result
HA2
(HA of MR2)
l
HA1 nne
(HA of MR1)
Internet e Tu
v
rn ati
A lte CN
FAILED
MR1 MR2
MNP1 &
MNP2
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8. Implementation Report
 Test-bed hardware
 2 ARs, 2 MRs, 2 MNs and some more machines (all Linux)
 Dynamic Switch (DS)
 All other machines are connected to DS
 DS simulates connectivity between nodes
 Software
 Modification of NEPL (NEMO Platform for Linux)
 Added several ICMPv6 messages, alternative tunneling
between Peer MR and HA, routing-based-on-source-address at
MR using ip6_queue and ip6tables
 Current status
 Almost done; gathering initial experimental results
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9. Implementation Report
 Physical topology of the test-bed
CN1 IPv6
Network
HA1
AR1 AR2
MR1 MR2
Dynamic
Switch MN1 9MN2
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10. Implementation Report
 Logical topology of the test-bed
IPv6
CN1 Network
HA1
AR1 AR2
Always
connected
Dynamic MR2
Connectivity
MR1
MN1 10MN2
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11. Implementation Report
 Test-bed hardware
 2 ARs, 2 MRs, 2 MNs and additional Linux machines
 Dynamic Switch (DS)
 All other machines are connected to DS
 DS simulates connectivity between nodes
 Software
 Modification of NEPL (NEMO Platform for Linux)
 Added several ICMPv6 messages, alternative tunneling
between Peer MR and HA, routing-based-on-source-address
using ip6_queue and ip6tables at MR
 Current status
 Almost done; gathering initial experimental results
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12. Summary
 We propose “Peer MR” relationship in
Multihomed NEMO
 Peer MR surrogates failed MR
 MN can take a seamless internet service
without session re-establishment
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13. Q & A
 Authors
 Jiho Ryu (jhryu@mmlab.snu.ac.kr)
 Nakjung Choi (fomula@mmlab.snu.ac.kr)
 Eunkyoung Paik (euna@kt.co.kr)
 Taekyoung Kwon (tk@mmlab.snu.ac.kr)
 Chulhyun Park (chpark@mmlab.snu.ac.kr)
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