Mobile IPv6 Fast Handovers for 3G CDMA Networks Hidetoshi Yokota KDDI Lab Gopal Dommety Cisco 65 th IETF MIPSHOP WG

2 Focus of this I-D Implement fast handovers in 3G CDMA networks  Adaptation of FMIPv6 (RFC4068) to 3G CDMA networks  FMIPv6 extensions  Clarifications Link-layer connection in the new network can be simplified by introducing FMIPv6  bootstrapping parameters can be obtained in FMIPv6 operation Selective bi-casting is considered  multiple/single IF(s)  bicasting at PAR/HA

3 Handover trigger & information in 3G CDMA networks Available information for the target network  pilot channels  cell information  serving nodes  location of BS or MN 3G core network NARPAR BS MN “Handover assist information” BS P-ANN-AN report C/I estimates pilot channel

4 Issues and possible solutions (1) The FBU may be delayed and the MN gets to the NAR before the handover is detected  bi-casting does not solve this situation it is more effective in the predictive mode If the predictive mode is failed, it falls back to the reactive mode (Sec 3.2 #2 in RFC4068)  a delayed FBU was not well taken into consideration in the previous (-01) I-D

5 Delayed FBU (case 1) MN PARNAR FBAck HI (Code:1) HAck forwarding RtSolPr PrRtAdv handover FNA[nFBU] Link-layer connection establishment+bootstrapping P-AN discard reactive mode nFBU (1) (2) (3) pFBU pFBU: transmitted in the previous network nFBU: transmitted in the new network pFBU: transmitted in the previous network nFBU: transmitted in the new network

6 Delayed FBU (case 2) MN PARNAR pFBU FBAck HI (Code:1) HAck forwarding RtSolPr PrRtAdv handover FNA[nFBU] nFBU Link-layer connection establishment+bootstrapping HI (Code:0) HAck (reject; Code: ) P-AN reactive mode address validity check reactive mode (1) (2) (3)

7 Delayed FBU (case 3) MN PARNAR pFBU forwarding RtSolPr PrRtAdv handover FNA[nFBU] Link-layer connection establishment+bootstrapping P-AN HI (Code:0) HAck (accept) FBAck reactive mode reactive mode predictive mode accept FNA ignore nFBU (1) (2) (3) address validity check

8 Issues and possible solutions (2) NAR is resolved by PAR with the New AP LLA In 3G networks, New AP LLA is not used  Handover assist information should be used  The length of the LLA Option is in units of 8 octets  Length of handover assist information may be information-specific In the last l-D, a new option-code in the LLA option was defined New Option is defined to convey handover assist information

9 New option for vendor-specific handover information | Type | Length | Option-Code | VS-Length | | VS-Value Type T.B.D. Length The size of this option in 8 octets including the Type, Length, Option-Code and VS-Length fields. Option-Code Indicates the particular type of vendor-specific information. This value is administrated by the vendor or organization that uses this option. VS-Length The size of the VS-Value field in octets. VS-Value Zero or more octets of vendor-specific information data.

10 Summary of primary changes from -01 draft Consideration of delayed FBU  When HI arrives at the NAR before FNA [FBU], it should behave as the predictive mode  otherwise, it should behave as the reactive mode New option to convey handover assist information is defined instead of extending LLA option