Mobile IP, and Micro Mobility

Gihwan Cho

[email protected]

Chonbuk National University, DCS Lab 1 presented by ghcho

Presentation Outline

 Our talk includes  Mobile IP, and Mobile IP in IPv6   micro mobility variants  HAWAII  Cellular IP  fast handoff  proactive, anchor handoff  hierarchical handoff  paging extension as a conclusion Chonbuk National University, DCS Lab 2 presented by ghcho

Mobile IP

 Now, let’s talk about  Mobile IP, and Mobile IP in IPv6   micro mobility variants  HAWAII  Cellular IP  fast handoff  proactive, anchor handoff  hierarchical handoff  paging extension as a conclusion Chonbuk National University, DCS Lab 3 presented by ghcho

Why Mobile IP ? (I)

  Background     Internet explosion increasing the mobile workforce, and mobile users increased reliance on networked computing prevailing the portable devices, technologies IPv4 routing considerations     two level hierarchical address structure (network id, host id) longest prefix (network id) matching based static routing  host id based routing may produce the scalability problem if a host moves around, the network id should be changed!

then, the routing scheme to the MH may not applied!!

 clearly, a corresponding host does not know (need not id – by network layering concept) the moving host’s current network Chonbuk National University, DCS Lab 4 presented by ghcho

Why Mobile IP ? (II)

 So, which layer should take charge of host mobility?  applications, transport? IP? NI?

 sure, IP could give to higher level protocols the abstraction that the network address remains unchanged, therefore Mobile IP  Mobile IP allows users of portable computers to move form one place to another and yet maintain transparent network access through the wireless link  Initially, it does not assumed in design phase, for the host mobility nature, so much appropriated to macro mobility  however, in the practical point of view, most moving entities have some degree of moving pattern, that is micro mobility family Chonbuk National University, DCS Lab 5 presented by ghcho

Protocol Overview (I)

[1][2]



Three steps with the protocol

   agent discovery: MAs may advertise their availability for they provide service, or a newly arrived MH may send a solicitation to learn if any prospective agents are present  ICMP router discovery [3] registration: when an MH is away from home, it registers its care of address with its HA  UDP control messages [1] [2] tunneling: datagrams sent to an MH is away from home must be tunneled to hide its home address from intervening routers  encapsulation protocol [4][5] Chonbuk National University, DCS Lab 6 presented by ghcho

Protocol Overview (II)

Mobile Node FA (FA) HA (HA) Correspondent Node Agent Solicitation Agent Advertisement Registration Request agent discovery Registration Request Registration Reply registration Registration Reply Data sent Data received

Chonbuk National University, DCS Lab 7

tunneling

presented by ghcho

Protocol Overview (III)

Correspondent HA Node

location registration data paths (before registration) packet tunneling data paths (after data paths (sent from MN)

Internet

registration)

FA

agent

Mobile Node

discovery host moving

Mobile Node

tunnel

FA

Chonbuk National University, DCS Lab 8 presented by ghcho

Triangle Routing on Mobile IP

Internet Host Home-based Location Reply Path Home Agent

Tunneling

FA MH k

Host Moving

 Triangle routing is undesirable :   Increased network utilization (sensitivity to network partition) Irregularity of performance variance Chonbuk National University, DCS Lab 9 presented by ghcho

Mobile IPv4 – revised (I)

 Specification that the SPI of the MN-HA authentication extension is to be used as part of the data over which the authentication algorithm must be computed  Specification that FA may send advertisements at a rate faster than once per second, but must be chosen so that the advertisements do not burden the capacity of the local link  Specification that FAs should support reverse tunneling, and HAs must support decapsulation of reverse tunnels presented by ghcho Chonbuk National University, DCS Lab 10

Mobile IPv4 – revised (II)

 Changed the pre-configuration requirements for the MHs to reflect its capability  An FA is not required to discard Registration Replies that have a home address field that does not match any pending Registration Request  Allowed registration to be authenticated by use of a security association between the MH and a suitable authentication entity acceptable to the HA  noted that HMAC-MD5 should be considered for use in place of the “prefix+suffix” mode of MD5 as originally mandated in RFC 2002 Chonbuk National University, DCS Lab 11 presented by ghcho

Mobile IPv4 – revised (III)

 Clarification that an MA should only put its own addresses into the initial list of routers in the mobility advertisement  RFC 2002 suggests that an MA might advertise other default routers  Specification that an MH must ignore reserved bits in Agent Advertisement, as opposed to discarding such advertisements  in this way, new bits can be defined later, without affecting the ability for MHs to use the advertisements even when the newly defined bits are not understood Chonbuk National University, DCS Lab 12 presented by ghcho

Mobile IPv4 – revised (IV)

 Specification that the FA checks to make sure that the indicated HA does not belong to any of its network interface before relaying a Registration Request  if the check fails, and the FA is not the MH’s HA, then the FA rejects the request with code 136  Specification that, while they are away from the home network, MHs must not broadcast ARP packets to find the MAC address of another internet node  Specification that an FA must not use broadcast ARP for an MHs MAC address on a foreign network  it may obtain the MAC address by copying the information from an Agent Solicitation or a Reg. Request transmitted from an MH Chonbuk National University, DCS Lab 13 presented by ghcho

Mobile IPv4 – revised (V)

 Specification that an FA’s ARP cache for the MH’s IP address must not be allowed to expire before the MH’s visitor list entry expires  Clarified that an HA must not make any changes to the way it performs proxy ARP after it rejects an invalid deregistration request   Specification that multi-homed HA must use the registered care-of address as the source address in the outer IP header of the encapsulated datagram Inserted “T” bit into its proper place in the Registration Request message format Chonbuk National University, DCS Lab 14 presented by ghcho

Micro Mobility – HAWAII

[6]

 Now, let’s talk about  Mobile IP, and Mobile IP in IPv6   micro mobility variants  HAWAII  Cellular IP  fast handoff  proactive, anchor handoff  hierarchical handoff  paging extension as a conclusion Chonbuk National University, DCS Lab 15 presented by ghcho

IP Micro Mobility – HAWAII (I)

 

Overview

  Handoff Aware Wireless Access Internet Infrastructure (by Lucent) domain-based approach for supporting mobility  approach : most user mobility is local to a domain  specialized path setup schemes  host-based routing entry Characteristics       reduce mobility related disruption to user application reduce the number of mobility related updated simplify QoS support improved reliability with soft-state transition provide macro mobility in conjunction with Mobile IP include the paging concept Chonbuk National University, DCS Lab 16 presented by ghcho

IP Micro Mobility – HAWAII (II)

 Mobility support for inter-HAWAII domain : Mobile IP  so, macro mobility  HAWAII protocol defines the mobility support for intra HAWAII domain, so, micro mobility     each router maintains a routing entry per moving host then, change only the corresponding entry on host moving as a result, in a domain, the overhead of top most router can be distributed into the lower-level routers host handoff may support by  a forwarding scheme  a non forwarding scheme Chonbuk National University, DCS Lab 17 presented by ghcho

IP Micro Mobility – HAWAII (III)

 Use path setup message to establish and update host based routing entries in selective routers in the domain -> where, how, and which routers are updates?

 Forwarding scheme : optimized for TDMA network  update the forwarding entry from old BS to new BS  Non forwarding scheme : optimized for CDMA network   update the forwarding entry from new BS to old BS Other routers has no MH’s current location  Forwarding entry must be updated in periodical, so soft state update, to prevent its out-of-state situation  refresh message Chonbuk National University, DCS Lab 18 presented by ghcho

IP Micro Mobility – HAWAII (IV)

Chonbuk National University, DCS Lab 19 presented by ghcho

IP Micro Mobility – HAWAII (V)

Chonbuk National University, DCS Lab 20 presented by ghcho

Forwarding Path Setup

Chonbuk National University, DCS Lab 21 presented by ghcho

Non-Forwarding Path Setup

Chonbuk National University, DCS Lab 22 presented by ghcho

Paging

 Network determines the exact location by paging to deliver packets  “idle” MHs update the network less frequently than “active”MHs  network has only approximate location information for idle MHs Chonbuk National University, DCS Lab 23 presented by ghcho

Hierarchy using Domain

Chonbuk National University, DCS Lab 24 presented by ghcho

Paging Design Goals

 Efficiency  limit updates from the MH when idle to conserve battery power  Scalability  push paging initiation closer to the base station  Reliability  allow paging initiation to occur at any router/base station (no single points of failure)  Flexibility  allow for fixed, hierarchical, or user-defined paging areas Chonbuk National University, DCS Lab 25 presented by ghcho

Paging Support … HAWAII (I)

Chonbuk National University, DCS Lab 26 presented by ghcho

Paging Support … HAWAII (II)

Chonbuk National University, DCS Lab 27 presented by ghcho

Router Operation

Chonbuk National University, DCS Lab 28 presented by ghcho

Paging with Mobile-IP

 When using FAs    group set of FAs into multicast group previous FA initiates paging impact of previous FA failure  When operating without FAs   paging initiated from HA globally visible multicast address or separate unicasts necessary  scalability is an issue Chonbuk National University, DCS Lab 29 presented by ghcho

Micro Mobility – Cellular IP

[7]

 Now, let’s talk about  Mobile IP, and Mobile IP in IPv6   micro mobility variants  HAWAII  Cellular IP  fast handoff  proactive, anchor handoff  hierarchical handoff  paging extension as a conclusion Chonbuk National University, DCS Lab 30 presented by ghcho

Cellular IP (CIP)

 Cellular IP is intended to:  specify a protocol that allows routing IP datagrams to an MH    provide local mobility and handoff support minimize packet losses with the location update delay interwork with Mobile IP to provide wide area mobility support  Design principles     location information is stored in distributed data bases location information referring to an MH is created and updated by regular IP datagrams location information is stored as soft state location management strategy is separated between the idle MH and the active MH Chonbuk National University, DCS Lab 31 presented by ghcho

Protocol Requirement

 Protocol requirement       a host connected to a cellular IP network must be able to send IP datagram to hosts outside the cellular IP network datagrams arriving to a cellular IP network should be delivered with high probability to the destination host datagram delivery in a cellular IP network should be take placed without leaving the cellular IP network an MH migrating between cellular IP network must be to use Mobile IP for wide area mobility, that is, a host in a cellular IP network has a home address with a care-of-address hosts inside a cellular IP network are identified by IP addresses, but these have no location significance hosts outside the cellular IP network must not need any updating or enhancement, i.e. they must remain unware of the host’s current location inside the cellular IP network Chonbuk National University, DCS Lab 32 presented by ghcho

Hierarchical Mobility Management (I)

 Global mobility with Mobile IP Chonbuk National University, DCS Lab 33 presented by ghcho

Hierarchical Mobility Management (II)

 Local mobility with cellular IP  fast handoff within a mobile access network  less load in the global Internet Chonbuk National University, DCS Lab 34 presented by ghcho

Wireless Overlay Networks

Chonbuk National University, DCS Lab 35 presented by ghcho

Mobile Access Network

Chonbuk National University, DCS Lab 36 presented by ghcho

Protocol Overview (I)

 Base stations periodically emit beacon signals to be locate the nearest base station by MHs  All IP packets transmitted by an MH are routed from the BS to the GW by hop-by-hop shortest path routing regardless of the destination address  Cellular IP nodes maintain routing cache  packets transmitted by the MH create and update entries in each node's cache, thus an cache entry maps the MH’s IP address to the interface through which the packet entered the node  The chain of cached mappings referring to a single MH constitutes a reverse path for downlink packets addressed to the same MH Chonbuk National University, DCS Lab 37 presented by ghcho

Protocol Overview (II)

   as the MH migrates, the chain always points to its current location because its uplink packets create new mappings and old mappings are automatically cleared after a soft state timeout To prevent its mappings from timing out, an MH can periodically transmit control packets  control packets are regular IP packets with empty payloads MHs that are not actively transmitting or receiving data but want to be reachable for incoming packets, let their routing cache mappings time out but maintain paging cache mappings   IP packets addressed to these MHs will be routed by paging caches paging caches have a longer timeout value than routing caches and are not necessarily maintained in every Node Chonbuk National University, DCS Lab 38 presented by ghcho

Mobile IP vs. Cellular IP

 Global mobility support vs. local fast smooth handoff Chonbuk National University, DCS Lab 39 presented by ghcho

Uplink Path : Shortest Path

Chonbuk National University, DCS Lab 40 presented by ghcho

Uplink Packets Create Location Information

Chonbuk National University, DCS Lab 41 presented by ghcho

Downlink Packets (I)

 Mobile IP’s centralized location management Chonbuk National University, DCS Lab 42 presented by ghcho

Downlink Packets (II)

 Cellular IP’s distributed location database Chonbuk National University, DCS Lab 43 presented by ghcho

Control Packet in Uplink if no Data or a Move Detected

Chonbuk National University, DCS Lab 44 presented by ghcho

Handoff is Automatic

Chonbuk National University, DCS Lab 45 presented by ghcho

Idle Host Location Management Tradeoff

Chonbuk National University, DCS Lab 46 presented by ghcho

Location Management of Idle Hosts

 Paging setup  paging cache maintains in just some selected nodes   broadcast if a node has not paging (and routing) cache paging cache is updated with a control packet, with longer timeout and less frequently Chonbuk National University, DCS Lab 47 presented by ghcho

Paging Cache Update with a move

Chonbuk National University, DCS Lab 48 presented by ghcho

Paging Route with Paging Cache

Chonbuk National University, DCS Lab 49 presented by ghcho

Cellular IP MH

 Each MH has two states in legal, active and idle  when the state changed from idle to active, it sends a route update packet to the gateway   if an MH is in the active state  the MH has to send a route update packet whenever it changes its current base station if an MH is in the idle state  the MH has to send a paging update packet whenever it enters a new paging area or it meets a predefined period Chonbuk National University, DCS Lab 50 presented by ghcho

Extensions to Cellular IP

 During handoffs between base stations within the same paging area, idle MHs may remain silent, as paging is performed within the entire paging area Chonbuk National University, DCS Lab 51 presented by ghcho

Cellular IP Considerations

   In Summary     distributed location management location information established by uplink IP packet soft state management location management of idle hosts is separated from active hosts Advantages      simple, self-sufficient nodes simple mobility management : just send control packet if no data no control messaging at handoff soft states give built-in fault tolerance handoff or faults do not differ from normal operation Any problems?  Load from control packets ...

Chonbuk National University, DCS Lab 52 presented by ghcho

Micro Mobility – Fast Handoff

[8]

 Now, let’s talk about  Mobile IP, and Mobile IP in IPv6   micro mobility variants  HAWAII  Cellular IP  fast handoff  proactive, anchor handoff  hierarchical handoff  paging extension as a conclusion Chonbuk National University, DCS Lab 53 presented by ghcho

Fast handoffs overviews (I)

 Fast handoffs are required in mobile IPv4 in order to limit the period of service disruption experienced by an MN  It can be usually achieved  by anticipating the movement of MN  by utilizing simultaneous bindings in order to send multiple copies of the traffic to potential MN movement locations  Simply, it is achieved by bicasting traffic to the previous FA and new FA while the MN moving between them  both a flat and a hierarchical mobile IPv4 model are considered Chonbuk National University, DCS Lab 54 presented by ghcho

Fast handoffs overviews (II)

 The anticipation of the MN’s movement is achieved  by tight coupling with layer 2 functionality which is dependent on the type of access technology used  Fast handoffs coupled to the layer 2   limit the total handoff delay to the time needed to perform the layer 2 handoff allow MN to initiate fast handoff through the previous FA without having direct access to the new FA  Fast handoffs may be applied to Mobile IP  by performing registrations with the HA using simultaneous bindings Chonbuk National University, DCS Lab 55 presented by ghcho

Simultaneous bindings (I)

 Simultaneous bindings in MIPv4  may be achieved by setting the ‘S’ bit in the Mobile IP Registration Request message sent by the MN    cause the receiving agents(HA, GFA, regional FA, previous FA) to add a new binding for the MN without removing any which are existing are likely to be useful when an MN using at least one wireless network interface moves within wireless transmission range of more than one FA cause the HA to send multiple copies of data packets towards multiple FAs which may be in the same region or domain Chonbuk National University, DCS Lab 56 presented by ghcho

Simultaneous bindings (II)

HA CN Internet : bicasting new FA MN old FA MN

Chonbuk National University, DCS Lab 57 presented by ghcho

Flat and Hierarchical MIPv4 model

 A flat and a hierarchical (with GFA) MIPv4 model

HA FA2 Internet FA1 AP1 AP2 MN

Chonbuk National University, DCS Lab

CN HA Internet GFA FA3

58

FA2 AP2 FA1 AP1 AP3 CN MN Visited Domain

presented by ghcho

Flat Mobile IPv4 (FMIPv4) (I)

 The wireless layer 2 technology allows the MN to be connected to multiple wireless access points simultaneously   the MN may solicit advertisements from FAs before completing handoffs The layer 2 handoff does not finished until the MN’s registration with the new FA which produces a simultaneous binding at the HA  Fast handoff requires the MN   to receive new agent advertisements through the old AP to perform a registration with the new FA through the old AP Chonbuk National University, DCS Lab 59 presented by ghcho

FMIPv4 (II)

  Initiating fast handoffs through the old FA   inter-FA solicitation piggy backing advertisements on layer 2 messaging Inter-FA solicitation   this solution assumes that the FA with which the MN is currently registered is aware of the IP address of the new FA once the current FA is aware of the address of the new FA  the current FA will send the new FA an agent solicitation message  the new FA will reply to the current FA by sending it an agent advertisement, then the current FA will send the agent advertisement to the MN  MN will send a registration request to the new FA through old AP served by the current FA Chonbuk National University, DCS Lab 60 presented by ghcho

FMIPv4 (III)

 Inter-FA solicitation :

MN 4. Agent advertisement AP current FA 3. Agent advertisement 1. Agent Solicitation 2. Agent advertisement 5. Registration Request 6. Registration Request 7. Registration Request new FA

Chonbuk National University, DCS Lab 61 presented by ghcho

FMIPv4 (III)

 Inter-FA solicitation :

Internet HA GFA 8. Registration request 3. Agent advertisement old FA 1. Agent solicitation 2. Agent advertisement 6. Registration request old AP 5. Registration request new FA new AP 7. Registration request

Chonbuk National University, DCS Lab

4. Agent advertisement MN

62 presented by ghcho

FMIPv4 (IV)

 Piggy-backing advertisements on layer 2 messaging     it is assumed that when an layer 2 handoff is initiated, old AP and new AP perform layer 2 messaging procedures to negotiate handoff since the MN is not attached to new AP yet  new FA is unaware of the IP address of the MN and cannot send an advertisement to it  it is necessary for the layer 2 procedures to interwork with MIP once an layer 2 handoff is initiated, such that old AP and new AP are in communication, it is possible for new AP to solicit an advertisement from new FA and transfer it to old AP when the advertisement is received by the MN, the MN can perform a registration directed to new FA even though the MN has no data-connection to new AP yet Chonbuk National University, DCS Lab 63 presented by ghcho

FMIPv4 (V)

 Piggy-backing advertisements on layer 2 messaging :

GFA Internet HA 7. Request registration 2. Reply advertisement new FA 3. Reply advertisement old FA old AP 1. Request advertisement 6. Request registration 5. Request registration new AP 4. Reply advertisement MN

Chonbuk National University, DCS Lab 64 presented by ghcho

Hierarchical Mobile IPv4 (HMIPv4) (I)

 HMIPv4 allows a MN to perform registrations locally with a Gateway FA(GFA) in order to reduce the number of signaling messages to the home network    it achieves a reduction in the signaling delay when a MN moves between FAs within a domain MN may be attached directly to any FA within the hierarchy and moves between FAs there may be multiple paths between MN and GFA  Triangle routing between nodes within the hierarchical domain is eliminated by direct routing through regional FAs or reduced by routing through the GFA Chonbuk National University, DCS Lab 65 presented by ghcho

HMIPv4 (II)

 HMIPv4 supplements with the following for Fat MIPv4  limitation of triangle routing for communication between hosts within the administrative domain   fast handoffs within the administrative domain considerations on regional deregistration  Regional tunnel management allows Regional Registrations within an administrative domain in order to avoid always having to perform registrations through HA   the GAF’s address always appears to the HA as the MN’s care of address some of the HA’s functionality is performed locally in the GFA Chonbuk National University, DCS Lab 66 presented by ghcho

Regional Registration (I) : HMIPv4

 When MN first arrives at a visited domain, it performs a registration with its home network

MN Regional FA 1. Registration Request 2. Registration Request GFA 3. Registration Request 6. Registration Reply 5. Registration Reply 4. Registration Reply HA

Chonbuk National University, DCS Lab 67 presented by ghcho

Regional Registration (II) : HMIPv4

 The Signaling message flow for RR

MN 1. RR Request 2. RR Request New FA GFA

Chonbuk National University, DCS Lab 68

4. RR Reply 3. RR Reply

presented by ghcho

Regional Registration (III) : HMIPv4

 FA announces its presence via an agent advertisement message  an agent advertisement message includes the corresponding addresses in order between its own address(first) and the GFA address(last) in the Mobility Agent Advertisement (MAA) extension  Once the home agent has registered the GFA address as the care of address of MN, MN may perform RR  When MN receives an agent advertisement from FA, MN can perform a RR with this FA and GFA Chonbuk National University, DCS Lab 69 presented by ghcho

Fast Handoffs (I) : HMIPv4

 When MN receives an agent advertisement with a MAA extension, MN must   be eager to perform new bindings be lazy in releasing existing bindings  MN may add a hierarchical FA extension to registration requests in order to identify the exact FA path  if MN has at least one existing binding with a FA, additional simultaneous RR performed  There are two ways that MN choices the appropriate HA address in the RR Request  MAA extension advertises FA and GFA address only  MAA extension advertises complete order of FAs in the branch Chonbuk National University, DCS Lab 70 presented by ghcho

Fast Handoffs(II) : HMIPv4

 MAA extension advertises FA and GFA address only  it is assumed that there is always a single path from the MN to the GFA     MN always performs RR using the GFA address as HA address and the advertising FA as care of address as the RR request is relayed towards the GFA, each FA receiving it will check whether it has an existing binding with the MN and whether RR has the ‘S’ bit set to request for simultaneous bindings if this is true and the RR is validated by the GFA, FAs activate the simultaneous binding upon receiving the RR Replay from the GFA it is not necessary to advertise to the MN all of the FA addresses in hierarchical branch Chonbuk National University, DCS Lab 71 presented by ghcho

Fast Handoffs(III) : HMIPv4

 MAA extension advertises FA and GFA address only

MN 1. Agent Advertisement 2. RR Request (MAA extension) New FA 3. RR Request 5. RR Reply 4. RR Reply GFA

Chonbuk National University, DCS Lab 72 presented by ghcho

Fast Handoffs(IV) : HMIPv4

 MAA extension advertises complete order of FAs in the branch      where multiple regional FA levels, and multiple paths from the MN to the GFA are present, it may be necessary for the MN to identify the common route FA using the complete list of FAs in the hierarchical branch MN must cache MAA extensions for its active bindings when MN receives an advertisement from new FA which has a different MAA extension, MN will be eager to perform a new binding MN compares the IP address in the new MAA extension with the ones it has cached for its active binding a regional FA receiving RR request with it’s own address as HA address may return a RR reply to the MN Chonbuk National University, DCS Lab 73 presented by ghcho

Fast Handoffs(V) : HMIPv4

 MAA extension advertises complete order of FAs in the branch

MN New FA 1. Agent Advertisement (MAA extension) 2. RR Request 3. RR Request 4. RR Request 7. RR Reply 6. RR Reply 5. RR Reply GFA

Chonbuk National University, DCS Lab 74 presented by ghcho

Micro Mobility - Proactive, Anchor Handoff

[9][10]

 Now, let’s talk about  Mobile IP, and Mobile IP in IPv6   micro mobility variants  HAWAII  Cellular IP  fast handoff  proactive, anchor handoff  hierarchical handoff  paging extension as a conclusion Chonbuk National University, DCS Lab 75 presented by ghcho

Proactive Handoff (I)

[10]

 Proactive handoff aims to limit handoff delay to the time needed to perform a L2 handoff  It is based on predicting the movement of MHs anticipating new points of attachment    first, it completes L2 handoff then starts to forward data to the MH it allows L3 registration to proceed finally, handoff control is driven by the network as opposed to MH Chonbuk National University, DCS Lab 76 presented by ghcho

Proactive Handoff (II)

 Movement Detection  when an FA is aware that an handoff is occurring at the link layer, a trigger is sent to the mobile IP protocol stack   a source trigger is one that is obtained by the old FA once the link layer detects that the MH is departing its coverage area a target trigger is one that is obtained by the new FA once the link layer detects that the MH is arriving in its coverage area Chonbuk National University, DCS Lab 77 presented by ghcho

Proactive Handoff (III)

 Source trigger proactive handoff

Move detect oFA HA GFA Internet 3. Registration Request 1. Handoff Request 2. Handoff Reply 4. Registration Reply nFA MN MN

Chonbuk National University, DCS Lab 78 presented by ghcho

Proactive Handoff (IV)

 Target trigger proactive handoff

oFA HA Internet GFA 3. Registration Request 1. Handoff Request 2. Handoff Reply 4. Registration Reply Move detect nFA MN MN

Chonbuk National University, DCS Lab 79 presented by ghcho

Proactive Handoff (IV)

 Functional components

MN FAAA DHCPv6 SMM HA1 HA2 HAn HAAA DHCPv6 HMM HA1 HA2 HAn SMM : Serving Mobility Manager HMM : Home Mobility Manager

Chonbuk National University, DCS Lab 80 presented by ghcho

Proactive Handoff (V)

 Proactive intradomain handoff

time

Mobile Node nSMM System Handoff Request DHCPv6 oSMM Handoff And Context Trans Request DHCPv6 Request DHCP v6Res Handoff And Context Trans Response BU BA System Handoff Response BU HAn HMM BU BA HAm BA BU : Binding Update BA : Binding Ack.

BU BA CNn Chonbuk National University, DCS Lab 81 presented by ghcho

Proactive Handoff (VI)

1. when the MN detects that it is moving to another new sub network that belongs to the same domain of the current sub network , it sends a System Handoff Request to the current SMM (oSMM) 2. the oSMM sends an handoff and Context Transfer Request to the new SMM (nSMM) 3. the nSMM allocates a new COA to the MN and returns back a handoff and Context Transfer Response to the oSMM 4. the oSMM allocates an HA for the MN to bicast the data destined to the MN to both old and new COA. The oSMM sends a System Handoff Response to the MN confirming the completion of the handoff process 5. when the MN receives the System Handoff Response from the oSMM and establishes a L2 connectivity with the new Chonbuk National University, DCS Lab 82 presented by ghcho

Proactive Handoff (VII)

BU : Binding Update BA : Binding Ack.

time

Mobile Node nSMM System Handoff Request DHCPv6 nFAAA oFAAA oSMM HAk DHCPv6 Req DHCP v6Res.

AAan HAndoff And Context Trans Request AAan HAndoff And Context Trans Res System Handoff Res RegReq AAA Reg Req BU BA HAAA HMM HA Chonbuk National University, DCS Lab 83 RegReq RegRes Reg Res AAA Reg Res BU presented by ghcho BA

Proactive Handoff (VIII)

1. when the MN detects that it is moving to a new sub-network that belongs to a different administrative domain, it sends a System Handoff request to the old SMM(oSMM) 2. the oSMM sends a AAan HAndoff and Context Transfer Request to the new SMM(nSMM) via the AAA infrastructure 3. the nSMM allocates new COA to the MN and returns back a AAA infrastructure 4. the oSMM allocates an HA for the MN to bicast the data destined to the MN to both old and new COA. The oSMM sends a System Handoff Response to the MN confirming the completion of the handoff process 5. when the MN receives the System Handoff Response from the oSMM and establishes a L2 connectivity with the new sub network it sends a Registration Request to the nSMM Chonbuk National University, DCS Lab 84 presented by ghcho

Proactive Handoff (IX)

6. the nSMM constructs a AAA Registration Request and sends it to the HAAA via the FAA 7. when the HAAA receives the AAA Registration Request, it attempts to authenticate the MN. If the MN’s authentication and authorization are affirmative, the request is forwarded to the HMM for further processing 8. the HMM updates the user state information. It then constructs a Registration Response message and subsequently forwards to the MN via the HAAA and the FAAA 9. once the MN receives a successful Registration Response from the network, it proceeds with the regular MIPv6 registration Chonbuk National University, DCS Lab 85 presented by ghcho

Fast vs. Proactive (I)

 Proactive 1. L2 handoff is completed 2. then, L3 registration is started

Internet GFA oFA oAP 1 2 nFA HA nAP

Layer 3 Layer 2

MN MN

Chonbuk National University, DCS Lab 86 presented by ghcho

Fast vs. Proactive (I)

 Fast 1. L3 registration is completed, rather than L2 handoff 2. Bi-Casting 3. it is not sure whether L2 handoff has completed

oFA Internet GFA 2 oAP 1 nFA nAP 3. L2 handoff MN MN HA

Layer 3 Layer 2 Chonbuk National University, DCS Lab 87 presented by ghcho

Anchor Handoff (I)

[11]

 Anchor handoff proposes a number of enhancements to ease local registration and global indirect registration  An MH authenticates with its HA during global registration and establishes a secure tunnel between the HA and FA  The FA then acts as anchor FA for future registrations  So, only a local registration is necessary after handoff  This rule holds as long as the MH moves within the same domain between the visiting FA and the anchor FA Chonbuk National University, DCS Lab 88 presented by ghcho

Anchor Handoff (II)

 Local registration

Tunnel FA2 HA

Home Network

Internet

Visited Network

FA1

Anchor

MN MN

Chonbuk National University, DCS Lab 89 presented by ghcho

Anchor Handoff (III)

 Global indirect registration

Tunnel FA2 HA

Home Network

Internet

Visited Network

FA1

Anchor

MN MN

Chonbuk National University, DCS Lab 90 presented by ghcho

Micro Mobility – Hierarchical Handoff

[12]

 Now, let’s talk about  Mobile IP, and Mobile IP in IPv6   micro mobility variants  HAWAII  Cellular IP  fast handoff  proactive, anchor handoff  hierarchical handoff  paging extension as a conclusion Chonbuk National University, DCS Lab 91 presented by ghcho

Hierarchical Mobile IP (I)

[13]

 Background    in Mobile IP  a mobile node registers with its HA each time it changes care-of address  if the distance between the visited network and the home network of the mobile node is large the signaling delay for these registration may be long it is solution for performing registrations locally in the visited domain : regional registrations by registering locally the signaling delay is reduced, and this may improve the performance of handover Chonbuk National University, DCS Lab 92 presented by ghcho

Hierarchical Mobile IP (II)

 Processing  when an MN first arrives at a visited domain, it performs home registration  during a home registration the HA registers the address of GFA(gateway FA) as the care-of address of the MH  this care-of address will not change when the MH changes FA under the same GFA  when changing GFA, MN must perform a home registration Chonbuk National University, DCS Lab 93 presented by ghcho

Hierarchical Mobile IP (III)

 HMIP employs a hierarchy of FAs to locally handle Mobile IP registration     MH send mobile IP registration messages to update their respective location information registration messages establish tunnels between neighboring FAs along the path from the MH to a GFA the use of tunnels makes it possible to employ the protocol in an IP network that carries non-mobile traffic as well typically one level of hierarchy is considered where all FAs are connected to the GFA  in this case direct tunnels connect the GFA to FAs that are located at access points Chonbuk National University, DCS Lab 94 presented by ghcho

Hierarchical Mobile IP (IV)

HA Correspondent Node Internet GFA IP registration message Tunnel Route from CN to MN after regional registration

Chonbuk National University, DCS Lab 95

FA FA

presented by ghcho

MN

Hierarchical Mobile IPv6 (I)

[14] [15]

 Background  in Mobile IPv6 there are no FAs, but there is still need to provide a central point to assist with MIP handoffs   similar to MIPv4, Mobile IPv6 can benefit from reduce mobility signaling with external networks by employing local hierarchical structure For this reason a new Mobile IPv6 node, called Mobility Server(MS), is used Chonbuk National University, DCS Lab 96 presented by ghcho

Hierarchical Mobile IPv6 (II)

 Features  as the existing hierarchical Mobile IP scheme it uses anchor points called mobility servers(MS) to deploy two levels of hierarchies (MS is called Mobility Anchor Point(MAP) in other IETF draft)    it uses of new IPv6 functionalities such as a large address space and neighbor discovery mechanisms to support flexible, scalable and robust mobility management supports two or more levels of hierarchy  the simplest implementation of HMIPv6 supports two levels of hierarchy (e.g. micro-mobility protocol and Mobile IP) each domain contains one or several MSs as the level of hierarchy Chonbuk National University, DCS Lab 97 presented by ghcho

Hierarchical Mobile IPv6 (III)

 Address allocation    if MH moves into new domain it gets two CoA  global CoA(GCoA) and local CoA(LCoA) If it moves within a domain  it only needs to change its LCoA  The GCoA remains the same MH register its GCoA with its HA and correspondent hosts   in contrast to HMIPv4 schemes, the GCoA is not the address of the MS but an address belongs to the MS’s subnet as a result, the MS can be changed dynamically without having to change the GCoAs of the MHs currently roaming in the domain Chonbuk National University, DCS Lab 98 presented by ghcho

Hierarchical Mobile IPv6 (IV)

 Processing  packets addressed to the MH’s GCoA are routed to the domain intercepted by the MS and encapsulated to the MH’s current LCoA Chonbuk National University, DCS Lab 99 presented by ghcho

Hierarchical Mobile IPv6 (V)

HA Correspondent Node Internet MS IPv6 router Route before registration Tunnel Intercept the packets Route from CN to MN after regional registration

Chonbuk National University, DCS Lab

IPv6 router

100

MN

presented by ghcho

Micro Mobility – Paging Extension

[16]

 Now, let’s talk about  Mobile IP, and Mobile IP in IPv6   micro mobility variants  HAWAII  Cellular IP  fast handoff  proactive, anchor handoff  hierarchical handoff  paging extension as a conclusion Chonbuk National University, DCS Lab 101 presented by ghcho

Paging Extensions for Mobile IP (I)

 P-MIP  is designed to reduce signaling load in the core Internet and power consumption of MHs  The state of MH   active mode : operate in exactly the same manner as in Mobile IP  when an MH changes its point of attachment, it registers with a new FA idle mode : register to HA after receiving paging request  in contrast, MH do not register when they move in a same paging area  it is forced to register only when it moves to a new paging area Chonbuk National University, DCS Lab 102 presented by ghcho

Paging Extensions for Mobile IP (II)

1. HA forward data packets to registered FA(rFA) 2. rFA checks MH’s information on record if it has, rFA checks that MH supports paging or not if it supports, rFA checks the MH’s state 3. If MH is in

active mode

, rFA decapsulates and forwards packets to the MH 4. If MH is in

idle mode

, rFA sends a paging request message to its own access network and other FAs in the paging area 5. When MH receives a paging request, it registers through the current FA to its HA 6. After receiving a registration request MH sends a paging reply back to its rFA through its current FA to inform the register FA of its current location 7. When rFA receives a paging reply, it forwards any buffered packets to the MH Chonbuk National University, DCS Lab 103 presented by ghcho

Paging Extensions for Mobile IP (III)

HA Data packets Paging request message 1 Internet FA 4 rFA 2 3 FA MN MN Paging area MN

104 Chonbuk National University, DCS Lab presented by ghcho

Paging Extensions for Mobile IP (IV)

HA Registration message Paging reply message Orphan data packets Internet 6 FA 7 rFA FA MN 5 MN Paging area MN

105 Chonbuk National University, DCS Lab presented by ghcho

As a Conclusion : Micro Mobility (I)

 Mobile IP WG is in the process of consolidating all contributions with the idea of having one standard    its filtering strategy is to eliminate any proposals that did not support tunneling and Mobile IP messaging initially 4 proposals has been considered, then 2 proposals, proactive and fast handoff were left in discussion at a moment, the WG is in the process of discussing the pos and cons of these 2 proposals Chonbuk National University, DCS Lab 106 presented by ghcho

As a Conclusion : Micro Mobility (II)

 Similarities of the proactive handoff and fast handoff  aim to limit delay to the time needed to perform a L2 handoff  make use of predicting the movements of MHs to anticipate new points of attachments  Differences of the proactive handoff and fast handoff   the former first completes L2 handoff, then starts to forward data to the MH, and finally, allows L3 registration to proceed : handoff control is driven by the network the later anticipates the movements of an MH allowing the MH to register with the new FA or GFA prior to L2 connectivity being established : handoff is initiated by MH Chonbuk National University, DCS Lab 107 presented by ghcho

As a Conclusion : Micro Mobility (III)

 Considerations  what is the minimal coupling between the L3 and L2 to facilitate fast handoff?

  is the predicting new access points in advance assumption reasonable?

MH initiated or network initiated?

 The process of consolidating these two proposals has recently resulted in a single proposal for fast and low latency handoff for Mobile IPv4, as well as Mobile IPv6 Chonbuk National University, DCS Lab 108 presented by ghcho

Reference (I)

[1] C. Perkins, “IP Mobility Support,” IETF RFC 2002, Oct. 1996.

[2] C. Perkins, “IP Mobility Support for IPv4, revised,” IETF Draft, draft-ietf mobileip-rfc2002-bis-03.txt, Sep. 2000.

[3] S. Deering, “ICMP Router Discovery Messages,” IETF RFC 1256, Sep. 1991.

[4] C. Perkins, “IP Encapsulation within IP,” IETF RFC 2003, Oct. 1996.

[5] C. Perkins, “Minimal Encapsulation within IP,” IETF RFC 2004, Oct. 1996.

[6] R. Ramjee, et. al., “HAWAII : a domain-based approach for supporting mobility in wide area wireless networks,” Proc. IEEE International Conference on Network Protocols, pp.283-292, 1999.

[7] A.Campbell, et. al., “Cellular IP,” IETF Draft, draft-ietf-mobileip-cellularip-00.txt, Dec. 1999.

[8] K. Malki, H. Soliman, “Fast Handoffs in Mobile IPv4,” IETF Draft, draft-elmalki mobileip-fast-handoffs-03.txt, Sep. 2000.

Chonbuk National University, DCS Lab 109 presented by ghcho

Reference (II)

[9] G. Tsirtsis, “Fast handovers for Mobile IPv6,” IETF Draft, draft-ietf-mobileip-fast mipv6-01.txt, Apr. 2001 [10] P. Calhoun, et. al., “FA Assisted Hand-off,” IETF Draft, draft-calhoun-mobileip proactive-fa-01.txt, Jun.2000.

[11] G. Dommety, “Local and Indirect Registration for Anchoring Handoffs,” IETF Draft, draft-dommety-mobileip-anchor-handoff-01.txt, Dec. 2000.

[12] E. Gustafsson, et. al., “Mobile IP Regional Registration,” IETF Draft, draft-ietf mobileip-reg-tunnel-02.txt, Mar. 2000.

[13] C. Castelluccia, L. Bellier, “Hierarchical Mobile IPv6,” IETF Draft, draft-castelluccia mobileip-hmipv6-00.txt, Jul. 2000.

[15] H. Soliman, et. al., “Hierarchical MIPv6 mobility management,” IETF Draft, draft-ietf mobiliip-hmipv6-03.txt, Feb. 2001.

[16] X. Zhang, et. al., “P-MIP : Minimal Paging Extensions for Mobile IP,” IETF Draft, draft-zhang –pmip-00.txt, Jul. 2000.

presented by ghcho Chonbuk National University, DCS Lab 110