1 Mobile IPv6 Fast Handovers for 3G CDMA Networks Hidetoshi Yokota KDDI Lab Gopal Dommety Cisco

2 Focus of the draft Not a focus but one benefit is FMIP over heterogeneous networks Implement fast handovers in 3G CDMA networks  adaptation of FMIPv6 to 3G CDMA networks  FMIPv6 extensions  Clarifications 3G CDMA WiFi WiMAX MN AR BS AP BS

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 Predictive fast handover MN (P-AN) PARNAR (Report estimate) (N-AN) FBU Link-layer connection establishment+bootstrapping Traffic CH assignment FBAck HI HAck buffering delivery Dest:NCoA RtSolPr[MN-LLA, NewAP-LLA] PrRtAdv (HO indication) FNA? data Search for a buffer for NCoA and deliver packets in it handover (one example of triggering) forwarding

5 Issues and possible solutions (1) 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 -> the LLA option needs extension... New Option-Code is defined in the LLA option to convey handover assist information | Type | Length | Option-Code | LLA

6 Issues and possible solutions (2) How FNA should be implemented?  PPP replaces FNA (FNA elimination) Always checks if buffer exists  New IPCP option for FNA (L2 implementation ) Checks if buffer exists when this option is received  FNA in RFC4068 is used (standard FNA)

7 Reactive fast handover Reactive mode may be more realistic when it is difficult to identify NAR in advance Reactive mode may cause more packet loss Optionally, PAR may buffer packets to offer loss less handover  FBU or lower-layer signaling can be used to trigger buffering

8 Sequence of the reactive mode MN PARNAR FBU / Lower-layer signaling FBAck HI HAck buffering forwarding Dest:PCoA RtSolPr PrRtAdv data Search for a buffer for PCoA and forward packets in it handover FNA[FBU] / FBU FBU Link-layer connection establishment+bootstrapping 3 ways to implement

9 Selective bi-casting Following cases are considered:  multiple/single IF(s)  bicasting at PAR/HA Use cases for 4 combinations and details are illustrated BS PARNAR HA MN

10 Summary Implement fast handovers in 3G CDMA networks  specify information that can be used as handover assist information  define mechanism to determine NAR from handover assist information  enhancing reactive fast handover  optimizing performance by buffering and bi-casting