Handoff Delay Analysis and Measurement for SIP based mobility in IPv6

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Handoff Delay Analysis and Measurement for SIP
based mobility in IPv6

• Nobuyasu Nakajima, Ashutosh Dutta, Subir Das and
  Henning Schulzrinne

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Outline

• Introduction
• Terminal Mobility Using SIP
• Handoff Delay in Mid-call SIP Mobility
• DAD
• Router Selection
• Testbed for Mobile Multimedia Communication Using
  IPv6
• Implementation of SIP Terminal Mobility
• Handoff Delay Measurement
• Conclusion

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Introduction(1/2)

• Why IPv6?
• The Limitation of IPv4 address space
• Network Address Translation ( NAT ) is used to
  circumvent the address space problem, but it fail
  to provide the global routability
• IPv6 is designed to solve the problem

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Introduction(2/2)

• IPv6 performance issues for real-time
  communication
• Emphasis on handoff delay due to DAD and router
  selection while visiting a new network and using
  SIP for mobility

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Terminal Mobility Using SIP(1/3)

• SIP basic procedure

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Terminal Mobility Using SIP(2/3)

• SIP terminal mobility pre-call

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Terminal Mobility Using SIP(3/3)

• SIP terminal mobility mid-call

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Handoff Delay in Mid-call SIP Mobility(1/2)

• Components of handoff delay in mid-call SIP
  mobility

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Handoff Delay in Mid-call SIP Mobility(2/2)

• Dtotal handoff delay
• D1switch lower layer medium to access network
• D2detect a new router and a new link
• D3recovery of communication with a CN after
  detecting a new link
• DAD
• Router Selection

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Duplicate Address Detection(DAD)

• DAD is to confirm the uniqueness of the IPv6
  address on the link
• Send a Neighbor Solicitation on the local link
• During the DAD process, this address (tentative
  address) cannot send and receive packets
• Additional delay in sending a re-INVITE
• Average delay caused by DAD is 1500ms

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Reuter Selection(1/2)

• Routing Table Update
• Incorporate the movement detection part of MIPL
  MIPv6 in our implementation as Aggressive Router
  Selection module
• Has its own router list and is updated
  independently
• Forcibly updates routing table after receiving
  router advertisement from a new access router,
  and delete all routers without the same prefix

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Reuter Selection(2/2)

• Neighbor Unreachability Detection (UDN)

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Testbed for Mobile Multimedia Communication Using
IPv6
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Implementation of SIP Terminal Mobility

• MNs SIP UA is modified to send re-INVITE with
  new IP address information to CN
• SIP UA is modified to pass the new IP address
  information of MN to voice communication tool
• In order to keep the delay small
• Modify the Linux kernel
• Skip the DAD process
• Select the new router through Aggressive Router
  Selection

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Handoff Delay Measurement(1/3)

• Handoff flow of SIP mobility in IPv6

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Handoff Delay Measurement(2/3)

• a) SIP mobility without kernel modification
• b) SIP mobility with kernel modification
• Handoff delay of signaling

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Handoff Delay Measurement(3/3)

• Handoff delay of media UDP packet

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Conclusion

• Modify the Linux kernel to avoid the DAD
• Select new router aggressively to avoid NUD
• Without the kernel modification240s
• With the kernel modificationwithin 450ms
• For some real-time applications, this may be too
  high