View
213
Download
0
Category
Tags:
Preview:
Citation preview
Chonbuk National University, DCS Lab presented by ghcho1
Mobile IP, and Micro Mobility
Gihwan Cho
ghcho@cs.chonbuk.ac.kr
Chonbuk National University, DCS Lab presented by ghcho2
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 presented by ghcho3
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 presented by ghcho4
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 – by network layering concept) the moving host’s current network id
Chonbuk National University, DCS Lab presented by ghcho5
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 presented by ghcho6
Protocol Overview (I) [1][2]
Three steps with the protocol agent discovery: MAs may advertise their availability for they pro
vide 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 presented by ghcho7
Protocol Overview (II)
Correspondent Node
HA (HA)FA (FA)Mobile Node
Agent Solicitation
Agent Advertisement
Registration Request
Registration Request
Registration Reply
Registration Reply
Data sent
Data received
agent discovery
registration
tunneling
Chonbuk National University, DCS Lab presented by ghcho8
Protocol Overview (III)
Internet
Correspondent Node
HA
FA
FA
data paths (before registration)
Mobile Node
Mobile Node
host movingagent discovery
location registration
data paths (sent from MN)
packet tunneling
data paths (after registration)
tunnel
Chonbuk National University, DCS Lab presented by ghcho9
Triangle Routing on Mobile IP
Triangle routing is undesirable : Increased network utilization (sensitivity to network partition) Irregularity of performance variance
HomeAgent
FA
Internet Host
MH kMH k
Tunneling
Reply PathHome-based Location
Host Moving
Chonbuk National University, DCS Lab presented by ghcho10
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
Chonbuk National University, DCS Lab presented by ghcho11
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 t
he “prefix+suffix” mode of MD5 as originally mandated in RFC 2002
Chonbuk National University, DCS Lab presented by ghcho12
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 rou
ters
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 a
bility for MHs to use the advertisements even when the newly defined bits are not understood
Chonbuk National University, DCS Lab presented by ghcho13
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 rej
ects 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 presented by ghcho14
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 presented by ghcho15
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
Micro Mobility – HAWAII [6]
Chonbuk National University, DCS Lab presented by ghcho16
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
IP Micro Mobility – HAWAII (I)
Chonbuk National University, DCS Lab presented by ghcho17
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 presented by ghcho18
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 s
tate update, to prevent its out-of-state situation refresh message
Chonbuk National University, DCS Lab presented by ghcho19
IP Micro Mobility – HAWAII (IV)
Chonbuk National University, DCS Lab presented by ghcho20
IP Micro Mobility – HAWAII (V)
Chonbuk National University, DCS Lab presented by ghcho21
Forwarding Path Setup
Chonbuk National University, DCS Lab presented by ghcho22
Non-Forwarding Path Setup
Chonbuk National University, DCS Lab presented by ghcho23
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
Paging
Chonbuk National University, DCS Lab presented by ghcho24
Hierarchy using Domain
Chonbuk National University, DCS Lab presented by ghcho25
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
Paging Design Goals
Chonbuk National University, DCS Lab presented by ghcho26
Paging Support … HAWAII (I)
Chonbuk National University, DCS Lab presented by ghcho27
Paging Support … HAWAII (II)
Chonbuk National University, DCS Lab presented by ghcho28
Router Operation
Chonbuk National University, DCS Lab presented by ghcho29
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
Paging with Mobile-IP
Chonbuk National University, DCS Lab presented by ghcho30
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
Micro Mobility – Cellular IP [7]
Chonbuk National University, DCS Lab presented by ghcho31
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 b
y regular IP datagrams location information is stored as soft state location management strategy is separated between the idle MH
and the active MH
Cellular IP (CIP)
Chonbuk National University, DCS Lab presented by ghcho32
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 place
d without leaving the cellular IP network an MH migrating between cellular IP network must be to use M
obile 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
Protocol Requirement
Chonbuk National University, DCS Lab presented by ghcho33
Global mobility with Mobile IP
Hierarchical Mobility Management (I)
Chonbuk National University, DCS Lab presented by ghcho34
Local mobility with cellular IP fast handoff within a mobile access network less load in the global Internet
Hierarchical Mobility Management (II)
Chonbuk National University, DCS Lab presented by ghcho35
Wireless Overlay Networks
Chonbuk National University, DCS Lab presented by ghcho36
Mobile Access Network
Chonbuk National University, DCS Lab presented by ghcho37
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 presented by ghcho38
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 cac
hes paging caches have a longer timeout value than routing caches
and are not necessarily maintained in every Node
Chonbuk National University, DCS Lab presented by ghcho39
Mobile IP vs. Cellular IP
Global mobility support vs. local fast smooth handoff
Chonbuk National University, DCS Lab presented by ghcho40
Uplink Path : Shortest Path
Chonbuk National University, DCS Lab presented by ghcho41
Uplink Packets Create Location Information
Chonbuk National University, DCS Lab presented by ghcho42
Downlink Packets (I)
Mobile IP’s centralized location management
Chonbuk National University, DCS Lab presented by ghcho43
Downlink Packets (II)
Cellular IP’s distributed location database
Chonbuk National University, DCS Lab presented by ghcho44
Control Packet in Uplink if no Data or a Move Detected
Chonbuk National University, DCS Lab presented by ghcho45
Handoff is Automatic
Chonbuk National University, DCS Lab presented by ghcho46
Idle Host Location Management Tradeoff
Chonbuk National University, DCS Lab presented by ghcho47
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 presented by ghcho48
Paging Cache Update with a move
Chonbuk National University, DCS Lab presented by ghcho49
Paging Route with Paging Cache
Chonbuk National University, DCS Lab presented by ghcho50
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 presented by ghcho51
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 presented by ghcho52
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 presented by ghcho53
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
Micro Mobility – Fast Handoff [8]
Chonbuk National University, DCS Lab presented by ghcho54
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 copie
s 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 presented by ghcho55
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 presented by ghcho56
Simultaneous bindings (I)
Simultaneous bindings in MIPv4 may be achieved by setting the ‘S’ bit in the Mobile IP Registrati
on Request message sent by the MN cause the receiving agents(HA, GFA, regional FA, previous FA) t
o 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 presented by ghcho57
Simultaneous bindings (II)
Internet
CN
HA
old FA
new FAMN
: bicasting
MN
Chonbuk National University, DCS Lab presented by ghcho58
Flat and Hierarchical MIPv4 model
A flat and a hierarchical (with GFA) MIPv4 model
MN
InternetHA CN
AP2
FA2FA1
AP1
GFAInternetHA
CN MN
AP2
FA2 FA1
AP1 AP3
FA3
Visited Domain
Chonbuk National University, DCS Lab presented by ghcho59
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 h
andoffs
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 presented by ghcho60
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 presented by ghcho61
FMIPv4 (III)
new FA
Inter-FA solicitation :
current FA1. Agent Solicitation
5. Registration Request
AP 3. Agent advertisement
2. Agent advertisement
4. Agent advertisement
6. Registration Request
7. Registration Request
MN
Chonbuk National University, DCS Lab presented by ghcho62
FMIPv4 (III)
Inter-FA solicitation :
3. Agent advertisement 5. Registration
request
6. Registration request
old FA new FA1. Agent solicitation
MN
2. Agent advertisement
4. Agent advertisement
InternetHA
GFA
7. Registration request
8. Registration request
old AP
new AP
Chonbuk National University, DCS Lab presented by ghcho63
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 se
nd 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 presented by ghcho64
FMIPv4 (V)
Piggy-backing advertisements on layer 2 messaging :
new FAold FA
5. Request registration
MN
2. Reply advertisement
1. Request advertisement
3. Reply advertisement
4. Reply advertisement
Internet
HA
GFA
7. Request registration
6. Request registration
new AP
old AP
Chonbuk National University, DCS Lab presented by ghcho65
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 presented by ghcho66
HMIPv4 (II)
HMIPv4 supplements with the following for Fat MIPv4 limitation of triangle routing for communication between hosts wit
hin 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 o
f address some of the HA’s functionality is performed locally in the GFA
Chonbuk National University, DCS Lab presented by ghcho67
Regional Registration (I) : HMIPv4
When MN first arrives at a visited domain, it performs a registration with its home network
GFA
HA
1. Registration Request
Regional FA
MN
2. Registration Request
3. Registration Request
4. Registration Reply
5. Registration Reply
6. Registration Reply
Chonbuk National University, DCS Lab presented by ghcho68
Regional Registration (II) : HMIPv4
The Signaling message flow for RR
GFA
1. RR Request
New FA
MN
2. RR Request 3. RR Reply
4. RR Reply
Chonbuk National University, DCS Lab presented by ghcho69
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 presented by ghcho70
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 simu
ltaneous 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 presented by ghcho71
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 th
e 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 receivin
g 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 presented by ghcho72
Fast Handoffs(III) : HMIPv4
MAA extension advertises FA and GFA address only
2. RR Request
New FA
MN
3. RR Request 4. RR Reply
5. RR Reply
GFA
1. Agent Advertisement
(MAA extension)
Chonbuk National University, DCS Lab presented by ghcho73
Fast Handoffs(IV) : HMIPv4
MAA extension advertises complete order of FAs in the branch where multiple regional FA levels, and multiple paths from the M
N 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 d
ifferent 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 presented by ghcho74
Fast Handoffs(V) : HMIPv4
MAA extension advertises complete order of FAs in the branch
2. RR Request
New FA
MN
3. RR Request
4. RR Request 5. RR Reply
6. RR Reply
7. RR Reply
GFA
1. Agent Advertisement
(MAA extension)
Chonbuk National University, DCS Lab presented by ghcho75
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
Micro Mobility - Proactive, Anchor Handoff [9][10]
Chonbuk National University, DCS Lab presented by ghcho76
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 M
H it allows L3 registration to proceed finally, handoff control is driven by the network as opposed to M
H
Chonbuk National University, DCS Lab presented by ghcho77
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 presented by ghcho78
Proactive Handoff (III)
Source trigger proactive handoff
Internet
nFA
MN
HA
oFA
MN
GFA
1. Handoff Request
2. Handoff Reply
3. Registration Request
4. Registration ReplyMove detect
Chonbuk National University, DCS Lab presented by ghcho79
Proactive Handoff (IV)
Target trigger proactive handoff
Internet
nFA
MN
HA
oFA
MN
GFA
1. Handoff Request
2. Handoff Reply
3. Registration Request
4. Registration Reply
Move detect
Chonbuk National University, DCS Lab presented by ghcho80
Proactive Handoff (IV)
Functional components
FAAADHCPv6
SMM
MN
HA1 HA2 HAn
HAAADHCPv6
HMM
HA1 HA2 HAn
SMM : Serving Mobility ManagerHMM : Home Mobility Manager
Chonbuk National University, DCS Lab presented by ghcho81
Proactive Handoff (V)
Proactive intradomain handofftime
System Handoff Request
Handoff And
Context Trans
Request
DHCPv6Request
DHCPv6Res
Handoff And
Context Trans
Response
BUBA
System Handoff
Response
BU
BUBA
BA
BU BA
BU : Binding UpdateBA : Binding Ack.
CNn
Mobile Node
HAn
nSMM
DHCPv6
oSMM
HMM
HAm
Chonbuk National University, DCS Lab presented by ghcho82
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 presented by ghcho83
Proactive Handoff (VII)
Proactive interdomain handoff Proactive interdomain handofftime
System Handoff Request
DHCPv6Req
DHCPv6Res.
BUBA
System Handoff
Res BU
BA
BU : Binding UpdateBA : Binding Ack.
Mobile Node
nSMM
DHCPv6
nFAAA
oFAAA
HAk
oSMM
HAAA
HMM
HA
AAan HAndoff And Context Trans Request
AAan HAndoff And Context Trans Res
RegReq
AAA Reg Req
RegReq RegRes
AAA Reg Res
Reg Res
Chonbuk National University, DCS Lab presented by ghcho84
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 presented by ghcho85
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 presented by ghcho86
Fast vs. Proactive (I)
Proactive
Internet
HA
GFA2
1. L2 handoff is completed
2. then, L3 registration is started
nFA
MN
oFA
MN
Layer 21
Layer 3
oAP nAP
Chonbuk National University, DCS Lab presented by ghcho87
Fast vs. Proactive (I)
Fast
Internet
HA
3. it is not sure whether L2 handoff has completed
2. Bi-Casting
1. L3 registration is completed, rather than L2 handoff
nFA
MN
oFA
MN
GFA
Layer 3
Layer 2
2
1
3. L2 handoff
oAPnAP
Chonbuk National University, DCS Lab presented by ghcho88
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 presented by ghcho89
Anchor Handoff (II)
Local registration
Internet
FA1
MN
HA
FA2
MN
Tunnel
HomeNetwork
Visited Network
Anchor
Chonbuk National University, DCS Lab presented by ghcho90
Anchor Handoff (III)
Global indirect registration
Internet
FA1
MN
HA
FA2
MN
Tunnel
Visited Network
HomeNetwork
Anchor
Chonbuk National University, DCS Lab presented by ghcho91
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
Micro Mobility – Hierarchical Handoff [12]
Chonbuk National University, DCS Lab presented by ghcho92
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 presented by ghcho93
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 presented by ghcho94
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 respec
tive location information registration messages establish tunnels between neighboring FA
s 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 c
onnected to the GFA in this case direct tunnels connect the GFA to FAs that are lo
cated at access points
Chonbuk National University, DCS Lab presented by ghcho95
InternetGFA
FA
MN
HA
FA
Correspondent Node
IP registration message
Tunnel
Route from CN to MN after regional registration
Hierarchical Mobile IP (IV)
Chonbuk National University, DCS Lab presented by ghcho96
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 si
gnaling 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 presented by ghcho97
Hierarchical Mobile IPv6 (II)
Features as the existing hierarchical Mobile IP scheme it uses anchor poin
ts 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 o
f hierarchy (e.g. micro-mobility protocol and Mobile IP) each domain contains one or several MSs as the level of hierarc
hy
Chonbuk National University, DCS Lab presented by ghcho98
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 t
he MS but an address belongs to the MS’s subnet as a result, the MS can be changed dynamically without having t
o change the GCoAs of the MHs currently roaming in the domain
Chonbuk National University, DCS Lab presented by ghcho99
Hierarchical Mobile IPv6 (IV)
Processing packets addressed to the MH’s GCoA are routed to the domain i
ntercepted by the MS and encapsulated to the MH’s current LCoA
Chonbuk National University, DCS Lab presented by ghcho100
Internet MSIPv6 router
MN
HA
Correspondent Node
Route before registration
Tunnel
Intercept the packets
Route from CN to MN after regional registration
IPv6router
Hierarchical Mobile IPv6 (V)
Chonbuk National University, DCS Lab presented by ghcho101
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
Micro Mobility – Paging Extension [16]
Chonbuk National University, DCS Lab presented by ghcho102
Paging Extensions for Mobile IP (I)
P-MIP is designed to reduce signaling load in the core Internet and powe
r 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 pag
ing area it is forced to register only when it moves to a new paging area
Chonbuk National University, DCS Lab presented by ghcho103
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 presented by ghcho104
Internet
rFA
MN
HAData packets
Paging request message
FA
MNPaging area
FA
MN
Paging Extensions for Mobile IP (III)
1
2
3
4
Chonbuk National University, DCS Lab presented by ghcho105
Internet
rFA
MN
HARegistration message
Paging reply message
Orphan data packets
FA
MNPaging area
FA
MN
Paging Extensions for Mobile IP (IV)
5
67
Chonbuk National University, DCS Lab presented by ghcho106
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 presented by ghcho107
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 p
oints 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 presented by ghcho108
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 presented by ghcho109
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-mobi
leip-rfc2002-bis-03.txt, Sep. 2000.[3] S. Deering, “ICMP Router Discovery Messages,” IETF RFC 1256, Sep. 199
1.[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 mobil
ity 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 presented by ghcho110
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.
Recommended