Dual Stack Moving Internet_ IPv4-IPv6 Traversal by bestt571

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									Dual Stack Moving
Internet: IPv4-IPv6
Traversal



                ETRI / PEC
             Sangjin Jeong
       <sjjeong@etri.re.kr>
Problems statement

     IPv4-IPv6 traversal of dual stack mobile nodes
 –        As IPv6 being deployed more widely, the dual stack mobile
          node will roam over IPv6-only networks or IPv4-only networks
 –        Conventional mobility management protocols support handover
          between IP networks with same IP stack
      •      Ex) MIP6 for IPv6, MIP4 for IPv4, NETLMM
 –        Maintaining IP connectivity during handover is difficult problem
      •      Especially, IPv6 connectivity in IPv4 networks or IPv4 connectivity
             in IPv6 networks


     There are two approaches
 –        MIPv6-based solution (Dual Stack Mobile IPv6, DSMIPv6)
 –        Network-based solution (Dual Stack Moving Internet, DSMI)


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MIPv6-based IPv4-IPv6 traversal solution




                      3
DSMIPv6 (Dual Stack Mobile IPv6)
- Problems of dual stack mobile nodes
 Mobile IP signaling is tightly coupled with the address family
  – MN needs to support both MIPv4 and MIPv6 for IPv4 and IPv6 network,
    respectively

 Deployment and operational issues motivate the use of a single
 mobility management protocol
  – Implementation burdens
      • Home agent supports both protocols or two separate Home Agents
        supporting the two protocols are needed
  – Operational burdens
      • Network operator to run two sets of mobility management protocols on the
        same network
      • Double the amount of configuration in the mobile node and the home agent
  – Mobility management inefficiency
      • MN sends two sets of signaling messages during handover
  – Impossibility of maintaining IP connectivity
      • It is difficult to maintain IP connectivity of MN’s IPv6 applications in IPv4 only
        and vice versa



                                          4
Overview

 Mobile nodes will, for a long time, need an IPv4 home address that
 can be used by upper layers
 Mobile nodes will move to networks that might not support IPv6 and
 would therefore need an IPv4 Care-of Address
 Allows the MN to roam over both IPv6 and IPv4, including the case
 where NAT is present on the path

 Extends Mobile IPv6 capabilities to allow dual stack mobile nodes to
 request that their home agent (also dual stacked) tunnel IPv4/IPv6
 packets addressed to their home addresses, to their IPv4/IPv6 care-
 of address(es)
 Mobile IPv6 offers a number of improvements over Mobile IPv4,
 mainly due to capabilities inherited from IPv6
  – Route optimization and Dynamic home agent discovery can only be
    achieved with Mobile IPv6

                                  5
Assumption & limitation

 MN and HA are both IPv4 and IPv6 enabled
 Only Mobile IPv6 is used between the MN and HA
 HA is always reachable through a globally unique IPv4
 address

 MN should be able to use an IPv4 and IPv6 HoA and
 CoA simultaneously and update their HA
 MN needs to be able to know the IPv4 and IPv6
 addresses of HA.
 MN needs to be able to detect the presence of a NAT
 device and traverse it.



                           6
Binding update scenarios (1/3)
- Foreign network supports IPv6 -
 MN is able to configure global IPv6 address
 MN send a binding update to the IPv6 address of its home agent, as
 defined in MIPv6 specification
 MN may have IPv4 home address if HA support IPv4 home address
 option


 Home network                   Foreign network
   IPv4/IPv6                          IPv6
                                                      Binding cache
     HA              v4 in v6        MN
                                                           IPv4    IPv6
                     v6 in v6                              CoA     CoA
                                                    IPv4            O
                                                            X
                                                    HoA           (if has)
  IPv4   IPv6                        IPv6
                CN                                  IPv6
                                                            X       O
                                                    HoA



                                 7
Binding update scenarios (2/3)
- Foreign network supports IPv4 only -
   MN tunnels IPv6 packets containing binding update to HA’s IPv4 address
   Binding update contains MN’s IPv6 home address
   Since MN’s CoA is IPv4, MN includes IPv4 CoA (IPv4-mapped IPv6)

  Home network                                  Foreign network
    IPv4/IPv6                                         IPv4
                                                                              Binding cache
          HA                                          MN
                                                                                     IPv4     IPv6
                                                                                     CoA      CoA
                                                                         IPv4          O
                                                                                                  X
                                                                         HoA       (if has)
       IPv4   IPv6                                      IPv4
                             CN                                          IPv6
                                                                                      O           X
                                                                         HoA


                                                               IPv4    IPv4       IPv4 or IPv6
IPv4      IPv4       IPv6   IPv6   IPv6   Mobility hdr (BU,     src     dst     (Packets to MN)
 src       dst        src    dst   HAO      IPv4 HAO)
                                                               HA      MN
MN’s     HA      MN’s CoA HA MN’s
CoA           (IPv4 mapped) IPv6 HoA                                  <data packet>
                                                  8
    Binding update scenarios (3/3)
    - Foreign network supports IPv4 only (NAT) -
        For NAT traversal, IPv6 packets are encapsulated in UDP and IPv4
        Content of IPv6 packet is identical to the public address scenario

        Home network                               Foreign network
          IPv4/IPv6                                 (private) IPv4
                                                                                 Binding cache
               HA                                       MN
                                                                                        IPv4      IPv6
                                             NAT                                        CoA       CoA
                                                                               IPv4        O
                                                                                                   X
                                                                               HoA     (if has)
         IPv4   IPv6                                    IPv4
                               CN                                              IPv6
                                                                                         O         X
                                                                               HoA


                                                                 IPv4   IPv4     UDP       IPv4 or IPv6
 IPv4   IPv4    UDP     IPv6   IPv6   IPv6   Mobility hdr (BU,    src    dst             (Packets to MN)
  src    dst             src    dst   HAO      IPv4 HAO)
                                                                 HA     NAT       <data packet>
NAT’s    HA            MN’s CoA HA MN’s
IPv4                (IPv4 mapped) IPv6 HoA          9
Route optimization, Dynamic IPv4 HoA
allocation

 Route optimization
  – When MN is in IPv6 foreign network, route optimization will
    operate same as MIPv6 (routing header)
  – In IPv4 foreign network, route optimization is not possible. MNs
    will need to communicate through HA
 Dynamic IPv4 home address allocation
  – When MN has no IPv4 HoA, it is possible to allow for the mobile
    node's IPv4 home address to be allocated dynamically
  – Done by including 0.0.0.0 in the IPv4 home address option
    included in the binding update




                                 10
Extensions to MIPv6 for tunnel setup

  IPv4 Home address option (present in the BU)
  IPv4 home address ack option (present in BA)
  NAT detection option (present in the BA)
  Protocol extensions
   – Setting up IPv6 in IPv4, IPv4 in IPv6 and IPv4 in IPv4
     tunnels
   – NAT detection and Traversal
   – Dynamic and static allocation of IPv4 home addresses




                                11
NETLMM-based IPv4-IPv6 traversal solution




                      12
DSMI (Dual Stack Moving Internet)
- Problem statement

 MIPv6-based solution is proposed in mip6 WG
  – MNs need to have mobility management protocol stack and require
    updates to the host software
  – MNs participate in mobility management signaling process
  – Location privacy problem may occur when the mobile node moves to
    other NETLMM domains


 Network-based localized mobility management architecture
 proposed by NETLMM WG supports IPv6 only
 However, as the NETLMM architecture being more widely used, it
 will be likely to introduce the NETLMM architecture to IPv4 networks
 Supports MN’s roaming over IPv6 and IPv4 NETLMM domains
  – Does not require additional host-side software update




                                   13
Design principles

  A mobile node has an IPv4/IPv6 dual stack
  A mobile node does not have any mobility management
  protocol stack
  A mobile node does not have any protocol stack for
  IPv4-IPv6 traversal
  A visiting NETLMM domain is either an IPv6-only or an
  IPv4-only network
  The expected solution of the NETLMM WG is used in a
  local NETLMM domain without any changes




                          14
Handover between NETLMM domains
supporting different IP versions

                                     Internet                 CN




             MAP                                MAP



   AR                                                    AR




     v4 NETLMM                      Movement          v6 NETLMM
       domain                                           domain

 Case 1 : CN (use of IPv4 applications)
 Case 2 : CN (use of IPv6 applications)
                                          15
Protocol operation – Scenario 1


    CN1
                                                                               Home domain
                                            MN => {MAP2, v4, v6}                  IPv4
                   Packet to MN
                                                               MAP1                             MN
                                                                                   AR1




                                                                 2. Binding Management                        1. Movement


                                                                                 Visiting domain
                                                                                        IPv6
          v6 src   v6 dst   Original packet to
                                                             MAP2                            MN
          MAP1     MAP2            MN                                          AR2


                                                                                MN => {MNID, IPv4 home addr}



                                   v6 src        v6 dst   Original packet to             Original packet to
                                   MAP2           AR2            MN                             MN

                                                    16
Protocol operation – Scenario 2


    CN1
                                                                                Home domain
                                             MN => {MAP2, v4, v6}                  IPv6
                   Packets to MN
                                                                MAP1                             MN
                                                                                    AR1




                                                                  2. Binding Management                        1. Movement


                                                                                  Visiting domain
                                                                                         IPv4
          v4 src    v4 dst   Original packet to
                                                              MAP2                            MN
          MAP1      MAP2            MN                                          AR2


                                                                                 MN => {MNID, IPv6 home addr}



                                    v4 src        v4 dst   Original packet to             Original packet to
                                    MAP2           AR2            MN                             MN

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Concluding remarks

 MIPv6-based IPv4-IPv6 traversal solution
  –   End-to-end intelligence (IETF philosophy)
  –   Mature technology (many implementations)
  –   Requires host-side software and protocol stack updates
  –   MN participates in mobility management signaling process


 Network-based IPv4-IPv6 traversal solution
  – No requirement for mobile node (dual stack)
  – Easy to administration (favorable to ISPs)
  – NETLMM WG is newly formed (long way to go)




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References

 Soliman, H., “Mobile IPv6 support for dual stack Hosts
 and Routers (DSMIPv6)”, draft-ietf-mip6-nemo-
 v4traversal-02 (work in progress), June 2006.
 Tsirtsis, G., “Mobility management for Dual stack mobile
 nodes A Problem Statement”, draft-ietf-mip6-dsmip-
 problem-02, June 2006.
 Kempf, J., "Problem Statement for Network-based
 Localized Mobility Management", draft-ietf-netlmm-
 nohost-ps-04 (work in progress), June 2006.
 Jeong, S., “Problem Statement for Dual Stack Moving
 Internet (DSMI)”, draft-jeong-netlmm-dual-stack-moving-
 ps-00 (work in progress), August 2006.

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