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Handover for PMIPv6 Using MIH. KANG Joon-Suk 姜 俊錫. Contents. Why Proxy MIPv6 Fast HO procedure Fast HO Time line Problems to be solved Vertical Handover Problems to be solved Comments. Agenda. Why Proxy MIPv6 Fast HO procedure Fast HO Time line
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Handover for PMIPv6 Using MIH KANG Joon-Suk 姜 俊錫
Contents • Why Proxy MIPv6 • Fast HO procedure • Fast HO Time line • Problems to be solved • Vertical Handover • Problems to be solved • Comments
Agenda • Why Proxy MIPv6 • Fast HO procedure • Fast HO Time line • Problems to be solved • Vertical Handover • Problems to be solved • Comments
Why Proxy MIPv6 • The provisioning of seamless mobility to moving nodes across homogeneous/heterogeneous access networks • Theoretical Target • IPv6 nodes • PC, Mobile phone, PDA, Web camera, Home application, VoIP phone, Mobile router, etc.. • Mobile/Multimedia applications….. • But actually No current targets…..
Why Proxy MIPv6 • Increasing number of Mobile node users.. • VoIP phone, PDA, Note book, • During walking • Voice/Video over IP phone • During riding moving vehicles • All devices to use Internet • Mobile router is strongly needed
Why Proxy MIPv6 • Normal MIPv6 was already completed • Leaded by mobile phone suppliers • NOKIA… • Heavy overhead to MN • Energy problem, Waste of air resources • There are no charming points to the Telecommunication Operator(supporting commercial services).
Why Proxy MIPv6 • Many vendors and Standard organizations were concerned about alternative technology. • CISCO, Juniper, WiMAX, 3GPP, IETF… • Proxy Mobile IPv6 • Proxy MIPv6 is good technology to support commercial service by Telecommunication Operators and router vendors.
Agenda • Why Proxy MIPv6 • Fast HO procedure • Fast HO Time line • Problems to be solved • Vertical Handover • Problems to be solved • Comments
MAG2 Scenario LMA • LMA : current home agent for the mn • pMAG : currently serving MAG • MAG1&MAG2 : candidate MAGs for a next MAG pMAG : serving MAG1 Handover MN
Protocol stack MAG LMA MN TARGETIEEE 802.16IEEE 802.11
Procedure LMA 1. MN is moving 2. Scan for Candidate Networks • To make the list of candidate networks • When the MN finds new network areas… pMAG : serving MAG1 1 2 Scan for Candidate Networks MAG2
2- How to Scan for Candidate Networks • Main method : Automatic method • Using Link_Detect event • The Link Detected event is generated on the MN when a PoA(Point of Attachment) of an access network is detected for the first time. • Automatically detected • Complement Manual method • Using MIH_Link_Actions(Link_Scan) command • To get a list of discovered PoAs and related information. • Manually trigger
2- How to Scan for Candidate Networks - Automatic LMA • During MN is moving, if the MN finds the new network area,Link_Detected event is generated on the MN • The event comprise the information of PoA • MN stores the PoA information • Making a list pMAG : serving MAG1 Scan for Candidate Networks MAG2
2- How to Scan for Candidate Networks - Passive MN pMAG nMAG MAC PMIPv6Client MIHFProtocol PoA(MAC) PoS(MIHF) PMIPv6Client MIISServer PoA(MAC) PoS(MIHF) PMIPv6Client MIH_Event_Subscribe.request{Link_Detected} Link_Detected Stores the link info. Link_Detected Link_Detected Stores the link info.
2- How to Scan for Candidate Networks - Active LMA 1. When Link_Going_Downoccures, 2. if the MN has no PoA informationor the confidence level of Link_Going_Down is low, 3. Start to scan for Candidate Networks=> Using MIH_Link_Actions(Link_Scan) command pMAG : serving MAG1 2 1 Link_Going_Down MAG2
2- How to Scan for Candidate Networks - Active MN pMAG nMAG MAC PMIPv6Client MIHFProtocol PoA(MAC) PoS(MIHF) PMIPv6Client MIISServer PoA(MAC) PoS(MIHF) PMIPv6Client Link Going Down withLow Confidence Level Link_Going_Down.indication MIH_Link_Going_Down.indication Scan for Candidate Network MIH_Scan.request Link_Action.request (LINK_SCAN) LINK_SCAN Link_Action.confirm(ScanResult) MIH_ScanResponse Stores the link info.
Procedure – contd. LMA 3. Link_Going_Down event occurs with High confidence level 4. Decision of Target MAG4-1. MN send PoA list to pMAG4-2. pMAG selects target MAG using the list. 4 pMAG : serving MAG1 2 1 3 Link_Going_Down(70%)
4- Target Decision • MIH_N2N_HO_Query_Resource command • By what parameters? • Signal strength? • It must be considered more
4- Target Decision MN pMAG nMAG MAC PMIPv6Client MIHFProtocol PoA(MAC) PoS(MIHF) PMIPv6Client MIISServer PoA(MAC) PoS(MIHF) PMIPv6Client Resource Availability Check MIH_N2N_HO_Query_Resource.request MIH_N2N_HO_Query_Resource.request … MIH_N2N_HO_Query_Resource.request MIH_N2N_HO_Query_Resource.response … MIH_N2N_HO_Query_Resource.response
Procedure – contd. LMA 7 5. pMAG makes MAG1 prepare handover • Sending “Trigger_L3_HO”message 6. Virtual PBU 7. Setup virtual BCE and Tunnel with MAG1 8. Virtual PBA 9. Setup Tunnel and Routing 6 8 pMAG : serving MAG1 5 9
Procedure – contd. LMA 10. Inform that virtual PBU is finished 11. LMA sends packets to MAG1 by the new tunnel, and MAG1 forwards them to pMAG • Because the MN is attaching to pMAG yet • The packets from the MN can be transferred by pMAG pMAG : serving 10 MAG1 11
Procedure – contd. ☞ In current stage • pMAG is serving the MN yet • LMA has two tunnels for the MN • with pMAG • with MAG1 • LMA has two cache entry for the MN • with pMAG • with MAG1 • Packet path from LMA to MN • LMA -> MAG1 –(forwarding)-> pMAG -> MN • Packet path from MN to LMA • MN -> pMAG -> LMA
Why Use Forwarding Path for Packets from LMA to MN • Forwarding path • MN -> pMAG -> LMA • Why? • To prevent the HO latency between LMA and MAG after L2 handover
Why Use Forwarding Path for Packets from LMA to MN LMA 1. LMA sends packets to MAG1 by the new tunnel, and MAG1 forwards them to pMAG • Because the MN is attaching to pMAG yet • The packets from the MN can be transferred by pMAG pMAG : serving MAG1 1
Why Use Forwarding Path for Packets from LMA to MN LMA 2~3. L2 HO • The L2 connection with pMAG is closed • New L2 connection is established with MAG1 4. Immediately, MAG1 can recognize that L2 HO was just finished. 5. MAG1 stops forwarding packets to pMAG at once 6. MAG1 starts to forward packets to MN directly 7 pMAG : serving 5 4 MAG1 8 11 9 2 3 6
Why Use Forwarding Path for Packets from LMA to MN • In case of normal PMIPv6, there must be time waste after L2 HO • When MAG1 informs LMA that L2 HO was just finished. • MAG1 has to send PBU to LMA, and then LMA has to send PBA to MAG1 • Total latency = 2 x delay(LMA ~ MAG1) • Too long latency • It’s the most part of total HO latency • In case of FMIPv6 • There is no time waste
Procedure – contd. 12. pMAG triggers L2 HO using MIH command • MIH_HO_Commit • Until L2 HO is finished, pMAG caches packets which come from MN and MAG1 caches packets which come from LMA. • During L2 HO, the MN stores packets destined for LMA 12 pMAG : serving LMA MAG1
Procedure – contd. 18 pMAG : serving LMA MAG1 13. L2 HO is finished 14. RS 15. RA 16. IP set up 17. pMAG sends the packets cached to MAG1 and MAG1 forwards them to the MN 18. pMAG releases all resources about the MN 17 14 15 16 13
Procedure – contd. pMAG LMA MAG1: serving 19. HO is totally finished 19
12- L2 HO procedure using MIH command MN pMAG nMAG MAC PMIPv6Client MIHFProtocol PoA(MAC) PoS(MIHF) PMIPv6Client MIISServer PoA(MAC) PoS(MIHF) PMIPv6Client MIH_N2N_HO_Commit.request Resource Availability Check MIH_N2N_HO_Commit Request MIH_N2N_HO_Commit.indication … MIH_N2N_HO_Commit.response MIH_N2N_HO_Commit Response … MIH_N2N_HO_Commit.confirm MIH_Net_HO_Commit.request MIH_Net_HO_CommitRequest L2 HO MIH_Net_HO_CommitResponse (Status = Success) MIH_Net_HO_Commit.confirm
12- L2 HO procedure using MIH command MN pMAG nMAG MAC PMIPv6Client MIHFProtocol PoA(MAC) PoS(MIHF) PMIPv6Client MIISServer PoA(MAC) PoS(MIHF) PMIPv6Client MIH_MN_HO_Complete.request MIH_MN_HO_CompleteRequest MIH_MN_HO_Complete.indication MIH_MN_HO_Complete.response MIH_MN_HO_CompleteResponse MIH_MN_HO_Complete.confirm
Agenda • Why Proxy MIPv6 • Fast HO procedure • Fast HO Time line • Problems to be solved • Vertical Handover • Problems to be solved • Comments
Time Line 1. Preparing HO MAGn LMA MAG1 … MN pMAG Serving Tunnel Beacon / Response to a probe Low Link_detect Stores the link info. Link_Going_Down(Low confidence) Link_Action(Link_Scan) Link_Scan Stores the link info. Link_Going_Down(High confidence) PoA List Resource Query Target Decision=> MAG1
Time Line 2. make before breaking LMA MAG1 MN pMAG Trigger_L3_HO Virtual PBU BCE Update Virtual PBA Tunnel Inform that virtual PBU is finished Packet forwarding(destined for MN) Packet forwarding(from MN)
Time Line3. Complete L2 HO LMA MAG1 MN pMAG Link_down Link_down Trigger_L2_HO BCE Update Packet caching Packet caching Tunnel L2 HO RS RA Serving HO complete release BCE Release
Agenda • Why Proxy MIPv6 • Fast HO procedure • Fast HO Time line • Problems to be solved • Vertical Handover • Problems to be solved • Comments
Problems to be solved • When does the ‘scanning for Candidate Networks’ start? • 1. After Link_Going_Down(Low confidence Level) message occurs ? • It acts totally up to Link_Going_Down event • But, I’m not sure whether Link_Going_Down can be performed to my wishes. • 2. Check the signal from serving MAG periodically. If it decreases to specific level, start ‘scanning’ • Additive technic is required. • It Maybe become a burden to the MN
Agenda • Why Proxy MIPv6 • Fast HO procedure • Fast HO Time line • Problems to be solved • Vertical Handover • Problems to be solved • Comments
Vertical Handover IPv6 Backbone MAG1 MAG2 Wireless LAN Interface 3GPP Interface .. .. .. MN MN MN 3GPP(Cellular) High speed wireless LAN L2 Link Detection & Interface SWAP Different Access Network Type
Why Vertical Handover • Cost/Capacity/Coverage….. • If a laptop might be able to use both a high speed wireless LAN and a cellular technology for Internet access. • Wireless LAN connections generally provide higher speeds • benefit of utilizing the higher bandwidth and lower cost • Cellular technologies generally provide more ubiquitous coverage. • better mobility support and larger coverage • The laptop user might want to use a wireless LAN connection whenever one is available, and to 'fail over' to a cellular connection when the wireless LAN is unavailable.
Two Issues of V-Handover • Multihoming problem. • There are many types of access network(L2) • Mobile Node : Multiple Interfaced Node. • Have to support unified signaling service between L2 and L3 regardless of L2 type • MIH
Reuse of the Fast-handover method • Fast-HO uses MIH events and commands between MAG and MN • Those events and commands are applicable to various L2 techniques • MIH_Event_Subscribe • Link_Detect • Link_Going_Down • MIH_N2N_HO_Query_Resource • MIH_Link_Actions(Link_Scan) • MIH_HO_Commit …. • The process between MAG and LAM has only L3 procedure • Independent on L2
Multiple Ifs for MIPv6 • Scenarios and Motivations for Multihomed mobile nodes • Need for ubiquitous access to the Internet • Need to redirect established sessions • Need to set up preferences • Need to select the best access technology • Need to dispatch traffic over distinct paths • Need for reliability • Need to accelerate transmission
IPv6 addressing methods • Auto-configuration is recommended • Stateless • ‘Network Prefix’(from Router) + ‘unique If ID’(from L2 address of If) • Statefull • DHCPv6 & ‘unique If ID’(from L2 address of If) • Manual-configuration • It is not related with If ID • Auto-configuration is strongly recommended • To improve efficiency of network management
IP changing problem • Session will break down after handover • Because of IP address changing MN MN Moving and Changing IP = Net Prefix + IF ID from MAC2 IP = Net Prefix + IF ID from MAC1
IP changing problem • To achieve seamless connection • IP address must not be changed • To get other advantages of multi-homing • Each Interface must have unique IP address • I will focus on ‘Seamless connection’
Using current RA method ? • I did not want to modify normal addressing system. • But, Router Advertisement message supports information about only auto-configuration.
Virtual Interface(Switch manager) ?? MN MAG RepresentativeIP address RepresentativeInterface ID MAG MN
Simple Modification of Auto-configuration process • MN must memorize representative Interface • The interface by which the MN is attached to LMA. • When the MN set up the IP address using auto-configuration method (by the information from RA) • To get a Interface ID, the MN uses the MAC address of representative Interface, instead of actual interface.
Simple Modification of Auto-configuration process MN MN Moving butno Changing IP = Net Prefix + IF ID from MAC2 IP = Net Prefix + IF ID from MAC1 IP = Net Prefix + IF ID from MAC1