Transcript Router Design for Scalable and Efficient Regional Registration

MOBILITY AND SERVICE MANAGEMENT
FOR FUTURE ALL-IP BASED WIRELESS
NETWORKS
Weiping He
Preliminary Proposal, Dec. 12, 2006
Committee:
Dr. Ing-Ray Chen, Committee Chair
Dr. Csaba Egyhazy
Dr. Mohamed Eltoweissy
Dr. Chang-Tien Lu
Dr. Gregory Kulczycki
1
Outline
 Introduction
 Research Statement and Methods
 Related Works
 Dynamic Mobility Anchor Points
 IMSA: Integrated Mobility and Service
Management Architecture
 Applications of Proxy for Integrated Cache
Consistency and Mobility Management
 Conclusion and Future Work
2
Mobility Management
Enables networks to locate the MN for service delivery and
to maintain active connections as the MN is moving.
 Location Management.
 Keep track the location of MNs.
 Include location registration and call delivery.
 Handoff Management.
 An MN keeps the connection active when the MN moves.
 Four tasks
 Deciding when to handoff
 Selecting a new AP
 Acquiring resources
 Informing the old AP reroute the packet and transfer state information.
3
Service Management
Ensures mobile nodes to get data services reliably,
correctly and efficiently.
 Service request management
Request handling: accept service requests and transform
requests into proper form.
Request delivery: forward server replies to the MN.
Request accounting, authentication and authorization (AAA)
 Service handoff management
An MN keeps its services connection when it moves from one
access point to another one.
4
Research Statement
Develop new mobility and service
management schemes for future all-IP
systems to minimize the overall network
cost.
Future all-IP based wireless networks provide
network services based on the ubiquitous
communication protocol: IP.
Using per user based proxy to integrate mobility and
service management to minimize the overall cost.
5
Future All-IP based Wireless Network
Architecture
 Home agent
IP Network
Home Agent
 Registration
 Current location
 Forward packets
 Correspond node
Correspondent Node
Provides various services
Access Router
 Access router
 Offers IP connectivity to MNs
 Powerful and flexible to host
proxies to perform cross
layers functions.
Access Point
Mobile Node
 Access Point
Offers the wireless link
connection to MNs
6
Research Challenges and Motivations
Mobile connectivity is highly variable.
Mobile nodes are relative resource-poor.
Workload to ARs is highly variable.
Mobility and service characteristics of MNs
are highly variable
Vast majority of terminals will be mobile in
a few years. The vast majority of traffic will
originate from IP-based applications.
7
Research Methods
Extensive background research.
Investigate of new techniques.
Performance study via modeling and
analysis.
Demonstration of the applicability of
proposed mobility and service management
schemes.
Simulation to validate analytical results.
8
Contribution
 Propose and analyze per-user regional
registration schemes for integrated mobility
and service management.
 Given a set of parameters characterizing the
operational and workload conditions of a MN,
there exists an optimal regional area size for
the MN such that the network communication
cost is minimized.
 Our scheme outperforms basic Mobile IPv6,
Mobile IPv6 Regional Registration, and
Hierarchical Mobile IPv6.
9
Network Layer Solutions (1) MIPv4
 An MN is identified by its home
address.
 If the MN is not in its home
area, it has another address
named Care of Address (CoA)
associated with its current
foreign location.
 The Home Agent maintains a
dynamic mapping between the
home address and CoA.
 A corresponding node always
sends packets to the MN by
the MN's home address.
 Pros: transparent to mobile
applications.
 Cons: Triangle routing issue,
CN HAFAMN , slow
handover.
Correspondent Node
Global Internet
Home Agent
Foreign Agent 1
Mobile Node
Foreign Agent 2
Mobile Node
10
Network Layer Solutions (2) Mobile IP
Regional Registration
 Purpose: to reduce the
location handoff overhead.
 Moves within the regional
registration area, MN only
performs a regional
registration to the GFA.
 Moves to another regional
area, MN will perform a
home registration.
 Packets path:
CNHAGFAFAMN
Correspondent Node
Global Internet
Home Agent
Gateway Foreign Agent 1
Foreign Agent 1
Foreign Agent 1
Mobile Node
Foreign Agent 1
Gateway Foreign Agent 2
Foreign Agent 1
Foreign Agent 1 Foreign Agent 1
Mobile Node
11
Network Layer Solutions (3) MIPv6
 The MN determines its
current location using the
IPv6 router discovery
protocol.
 The MN uses the IPv6
address auto configuration
mechanism to acquire a
care of address (CoA) on
the foreign link.
 The MN notifies its home
agent and CN for CoA
change.
Mobile Node
move
Home Link
Link A
Router
Router
Internet
Link B
Link C
Router
Home Agent
Correspondent Node
12
Compare MIPv6 with MIPv4
Mobile IPv4
Mobile IPv6
Mobile Node, Home Agent
same
MN's home address
Globally routeable home address and link-local
home address
Foreign Agent
A “plain” IPv6 router on the foreign link (Foreign
Agents no long exist)
Foreign Agent care-of address vs.
Collocated care-of address
All care-of address are collocated
Care-of address obtained via Agent
Discovery, DHCP, or manually
Care-of address obtained via stateless address
autoconfiguration, DHCP , or manually
Agent Discovery
Router Discovery
Authenticated registration with home
agent
Authenticated notification of home agent and
other correspondents
Routing to mobile node via tunneling
Routing to mobile node via tunneling and source
routing
Route optimization via separate protocol
specification
Integrated support for route optimization
13
Hierarchical Mobile IPv6 (HMIPv6)
HA
RCOA_1
Internet
MAP
AR
CN
AR
MAP
binding
RCOA_2
binding
binding
AP
AP
AP
AR
AP
AR
AR
AR
AR
AR
RCOA_1
LCOA’
AP
AP
Micro mobility
Access network
RCOA_1
LCOA
Macro mobility
RCOA_2
LCOA’’
Access network
Mobility Anchor Point (MAP)
14
http://www.ietf.org/rfc/rfc4140.txt
Application Layer Solutions
Session Initiation Protocol (SIP)
 An application layer protocol used to initiate, modify and terminate
network sessions.
 Four elements: users agents, registrars, proxy servers and redirect
servers.
 To support mobility.
 SIP server in MN's home network receives registrations from the MN
whenever the MN changes its location.
 When the CN send an INVITE SIP message to the MN, the redirect server
knows the current location information of the MN and forwards the INVITE
message to the MN.
 If a MN moves during an active session, it must send a new INVITE
message to the CN using the same call ID. The new IP address is put in
the contact field of the SIP messages. The CN will send future SIP
messages to the new address.
 If the MN is far away from the home network, every time it moves, it will
send a new registration to the home SIP server. This may incur a high
load.
15
Summary of the mobility support approaches
Mobility support
Link Layer
Solutions
IAPP
Network Layer
Solutions
Base protocol
MIPv4 MIPv6
…...
Tunnel
based
Regional
Registration
HMIPv6
Transport Layer
Solutions
Multicasting
approach
…...
MSOCKS
Applicatoin Layer
Solutions
SIP
…...
End to End
Solutions
…...
Per Host
Forwading
IDMP
…...
Cellular
IP
HAWAII
…...
16
Service Management Approaches
 Result Delivery Protocol (RDP)
Using a service proxy to provide reliable message
delivery to MNs. Created when a MN initiates a new
series of service requests.
Provide a fixed location for the reception of server
replies, keep track of pending requests, store the
request results, and forward the results to the MSS.
Runs on the application layer, suitable only for
connectionless request-reply communications.
The proxy moves whenever the MN moves across a
location boundary, may incur a high communication cost.
17
Service Management Approaches (continued)
 Mobile service management schemes based on location-aware mobile
service proxies in PCS.
 The personal proxies work as intelligent client-side agents to
communicate with services.
 The proxies cooperate with location management system, it is
location-aware and can optimally decide when and how often it
should move with the roaming user.
 Per-user integrated location and service management in PCS networks
 A per-user service proxy is created to serve as a gateway between
the mobile user and all client-server applications
 The service proxy co-located with location database.
 When there is a location handoff, a service handoff also happens to
co-locate the service proxy with the location db. This allows the
proxy to know the location of the mobile user to reduce the
communication cost for service delivery.
18
Service Management Approaches (continued)
 The above approaches are in the context of
HLR/VLR based PCS networks,
MSS, VLR and HLR in PCS networks are powerful
devices to perform both routing and computational
functions. Routers in IP networks normally are specific
routing devices.
PCS networks have regular shapes. IP subnets are
shapeless.
Distance can be used to measure network cost in PCS.
In IP networks, the network cost is normally measured
by hops, which do not equal to distances.
19
Dynamic Mobility Anchor Points Scheme
Assumption: access routers are restricted to perform
network layer functions.
Determine best DMAP domain size per MN dynamically
according to its mobility and service characteristics to
reduce network and signaling cost
 Dynamic Mobility Anchor Points (Access routers chosen)
for each MN
 MN determines dynamically when and where to launch
DMAP for minimizing network cost
 DMAP domain size depends on MN’s mobility and
service characteristics
 HA and CN know MN by RCoA
20
DMAP (continued)
 After service area is crossed, MN selects AR of
subnet just crossed as DMAP:
 MN determines size of new service area
 Obtains RCoA & CoA from current subnet
registers (RCoA,CoA) to current DMAP by
binding request message
 Inform HA and CN of new RCoA using standard
Mipv6
 Packet delivery route: CN->DMAP->MN
(tunneling or direct)
21
DMAP (continued)
MN’s service area - K, IP subnets
Goal : Dynamically determine optimal
service area (K) per MN
Special case :
K is constant for all MN’s
Degenerates to HMIPv6
K is 1
Degenerates to MIPv6
22
Diagram
HA
Internet
RCOA_1
Access network
AR DMAP
binding
CN
binding
AR DMAP
RCOA_2
tunneling
AR
AR
AR
AP
tunneling
AP
RCOA_1
LCOA’
AP
AP
AP
RCOA_2
LCOA’’
Access network
RCOA_1
LCOA
Dynamic Mobility Anchor Point (DMAP)
23
Trade-off
Large Service area : DMAP not change
often
Communication cost for service data delivery
high : CN->DMAP->MN
Location update cost is low
Small Service area : DMAP changed often
Communication cost for service data delivery
low
Cost of informing HA and CN of DMAP change
is high
24
Stochastic Petri Net Model
K
(Guard:Mark(Xs) < K-1
tmp
Pi=1
A
Xs
K
Moves
MN2DMAP
Pj=1
NewDMAP
Move
B
(Guard:Mark(Xs) = K-1)
(Guard:mark(Xs)=K)
25
Service Cost
 C i,service : Network communication overhead to
service a data packet when MN in i th subnet in
service area
Communication
delay in the
wireless link
from the AR to
the MN
Delay between
the DMAP and a
CN in the fixed
network
Delay from
DMAP to the AR
of the MN’s
current subnet in
the fixed network
26
Location Cost
C i,location : Network signaling overhead to service
a location handoff when MN in i th subnet in
service area
Clocation : Average communication cost to service
a move operation by MN weighted by respective
Pi probabilities
i = K : Location +
Service to inform HA
and N CNs of RCoA
change
i < K : MN inform
DMAP of CoA
change
27
Total communication cost
Total communication cost per time unit
 : Data packet rate between MN and CNs
 : MN’s mobility rate
28
Comparing DMAP with Basic MIPv6 and
HMIPv6
DMAP area large
(mobility cost
reduction)
DMAP degenerates
to HMIPv6
DMAP stays close
to MN to avoid CNDMAP-MN(service
cost reduction)
Degenerates to
Basic MIPv6
29
Justify the assumption of F(K)
Cost difference curves
are not sensitive to form
of F(k)
Assumption of F(k)
justified
30
IMSA: Integrated Mobility and Service
Management Architecture
Assumption:
Access routers are powerful and flexible.
Mobile proxies can be dynamically
downloaded and roam the access routers
to perform network layer and application
layer functions on behalf of users and
applications.
31
IMSA on Mobile IP v4
 A client-side proxy is created to
serve as a GFA as in the MIP-RR
to maintain the location
information of the MN.
 The proxy will communicate with
the correspondent node on
behalf of the MN.
 The proxy will move only when
the MN crosses a service area
thus incurring a service handoff.
 The service area size depends
on the mobility and service
characteristics of the MN.
 Goal: network cost associated
with mobility and service
handoffs will be minimized.
Correspondent Node
Home Agent
IP Network
IP Access
Router
A
B
Service Area 1
D
C
Service Area 2
IP Access Wireless Network
32
Message Flow in IMSA-MIPv4
Foreign
FA
Agent
Mobile Node
Service
Proxy
Home Agent
Correspondent
Node
1. Service Request
2. Forward to Proxy
3. Request to CN
Service
Request
4. CN Response
5. Forward Response
6. Forward Response
Foreign
Agent 1
Mobile Node
Foreign
Agent 2
1.Location
register
Move within
a service
area
Service
Proxy
Home
Agent
Correspondent
Node
2. Foward to
proxy
3.send ACK to FA2
4. Proxy send cancel msg to FA1
5. FA2 send ACK msg to MN
6. FA1 return cancel ACK to proxy
33
Service Handoff Process when Crossing
a Service Area in IMSA-MIPv4
Foreign
Agent 1
Mobile Node
Service
Proxy 1
Foreign
Agent 2
Service
Proxy 2
Home Agent
Correspondent
Node
1. Location update msg
2. Location update
Handoff to
another
location area
- mobility
management
3. Location update
request
5. Location
update ACK
6. Location Update ACK
4. Location update
ACK
7. cancel msg
8. cancel msg
1. service handoff request
Handoff to
another
service area
- service
management
2. service handoff request
3. service handoff request
4. service handoff ACK
6. service Update ACK
5. service handoff ACK
7. cancel msg
8. cancel msg
Boundary
34
Performance Model for IMSA-MIPv4
35
Optimal Service Area Size Kopt with
varying SMR and nct in IMSA
There exists an optimal
proxy service area size to
minimize the overall
communication cost when
given a set of parameter
values characterizing the
mobility and service
behaviors of the MN and
the network conditions of
the Mobile IP network.
36
Comparison of the IMSA-MIPv4 with
Mobile IP v4.
 The total cost increases
with the increase of
SMR for both schemes
 Less communication
overhead, especially
pronounced when SMR
is high.
37
Comparison of the IMSA-MIPv4 with MIPRR with Route Optimization.
 Total cost increases
with the increase of
either λor σ.
 IMSA-MIPv4 incurs
less communication
overhead than MIPRR, especially
pronounced when λor
σis high.
38
Optimal Service Area Size as a Function
of nct
 Initially increases.
 Context transfer cost
becomes high, stay in
a large service area
to avoid handoff.
 The cost of context
transfer would
dominate the cost if
nct is large.
39
Optimal Service Area Size as a Function
of SMR
 When SMR increases,
Kopt decreases.
 When SMR is small, the
σis high compared to the
λ; thus, the mobility
management cost is
larger than the service
management cost. The
proxy likes to stay at a
larger service area to
reduce the location
handoff cost.
40
IMSA on Mobile IP v6
 IMSA-MIPv6 and the DMAP are similar. They
differ only by the way of mapping a MN's RCoA
to its CoA.
The DMAP design maps RCoA to CoA by having the
current MAP maintain an internal table, so the MAP can
intercept a packet destined for RCoA and forward it to
the MN's CoA.
The IMSA-MIPv6 design maps RCoA to CoA by having
a proxy run on the MAP directly receive a packet
destined for RCoA, so the proxy can in turn forward the
packet to the MN's CoA.
41
PICMM: Proxy-Based Integrated Cache Consistency
and Mobility Management Scheme in Mobile IP
Systems
 Stateful cache consistency strategy: cache
invalidation messages are asynchronously sent
by the server the MN whenever data get
updated.
 A per-user proxy to buffer invalidation messages
to reduce uplink requests when reconnected.
 The proxy serves as a gateway foreign agent to
keep track of the address of the MN in a region.
 Identify the optimal regional area size to
minimize the overall network traffic cost, due to
cache consistency management, mobility
management, and query requests/replies.
42
Cache invalidation strategies
 Stateful strategy:
When there is an update to a data object, the server will
send an invalidation message to those MNs that keep a
cache copy.
 Stateless strategy:
The server will broadcast information on data objects
that have been updated either periodically or
asynchronously.
 Problem: if an MN misses invalidation reports
while it is disconnected, it will have to discard
the cache content after it reconnects.
43
The proxy’s three functions
 Working as a GFA as in regional registration to
keep tracking MN's location;
 Acting as a service proxy for services engaged
by the MN;
 Allocating a buffer space to store service context
information for each MN. The proxy will receive
invalidation reports from the server on behalf of
the MN. If the MN is connected, the proxy will
forward them to the MN. If the MN is
disconnected, the proxy will store them in the
buffer. Once the MN is reconnected, the MN will
get the latest invalidation reports from the proxy.
44
Integrated cache and mobility
management scheme
Correspondent Node
Home Agent
IP Network
Foreign Agent
Foreign Agent
Foreign Agent
Proxy
Proxy
ProxyCache
ProxyCache
A
B
MNCache
MN
MNCache
MN
C
MNCache
MN
Service Area 2
Service Area 1
IP Access Wireless Network
45
Cache invalidation process
The client-side proxy
receives an invalidation
report from the CN
when there is an update
to a cached data object;
MN is
connected?
N
Y
The proxy forwards the
invalidation report to
the MN
The proxy stores the
invalidation report in
ProxyCache;
When the MN wakes
up, the proxy forwards
the invalidation report.
46
Query Process
Query request for
a data object
Data object
requested is in the
MN's cache and
valid?
Y
Cache hit;
The MN returns the
query result
N
Cache miss;
User request is sent to
the proxy
Proxy forwards the
request to the CN;
CN returns a copy of
the requested object
to the proxy;
Proxy forwards the
data object to MN;
MN stores data object
in MNCache and
returns query result.
47
Disconnection Support
MN just reconnects to
wireless network;
MN is in the
same subnet as the
proxy?
N
Y
The MN gets
invalidation reports from
ProxyCache
Proxy moves to MN's
current subnet;
ProxyCache is moved
with the proxy;
The proxy informs the
HA and CNs of its
address change
The MN gets
invalidation reports
from ProxyCache.
48
Parameters
The on/off (or wake/sleep) behavior of the
MN: while the MN is in a wake state, it will
go to sleep with rate ωw, while the MN is in
a sleep state, it will wake up with rateωs.
The residence time that the MN stays in a
subnet while it is in a wake state.
Service traffic between the MN and server
applications
49
Parameters
50
Performance model
Just
Wake
up
Sleep
Wake2Sleep
ωw
Sleep2Wake
ωs
InquiryingProxy
#(Xs)
Moves
Moving
Xs
MN2Proxy
K
MovingProxy
K
51
Cost Function Derivation
Total cost
Effective data query rate is query arrival rate
multiplied with the probability of the MN is being
awake, λQ is the aggregate query arrival rate
Probability of the MN being in the awake state
The effective mobility rate is the mobility rate
multiplied with the probability of the MN being awake
Effective data update rate is simply the
aggregate data update rate
52
Query Cost
Cquery can be calculated as a weighted
average in all states
No query is issued while the MN is in sleep
If cache miss, the
query cost will be
MNProxyCN
Competition between
effective query arrival
rate and the update rate
When the MN just
wakes up, the MN
will first check with
the proxy for the
cache status when
answering a query,
and, if cache miss,
will get a copy from
the server.
53
Mobility cost
Cmobility can be calculated as a weighted
average in all states
When the MN is in the sleep state, there is no location cost
When the MN just wakes up, it will look for its proxy. If the MN
does not move during sleep, the cost is contacting the current AR
If move within service
area, MN only informs
the proxy of the CoA
change
Just wakes up, If moves during
sleep, proxy is moved to the
current subnet, the cost includes
context transfer cost and informing
the HA and CNs the change of the
proxy’s CoA
If moved K subnets, location handoff also
triggers a service handoff, the cost includes
context transfer cost and informing the HA
and CNs the change of the proxy’s CoA
54
Invalidation cost
Cinvalidation can be calculated as
a weighted average in all states
If the MN is in sleep or just wake-up mode, then
the invalidation report is buffered in the proxy.
Otherwise, the cost is from the CN
through the proxy to the MN
55
Numerical results (1)
 Kopt vs. λ{q,i} .
 Kopt decreases slowly
λ{q,i} increases.
 As λ{q,i} increases, the
query cost increases,
and subsequently the
MN prefers a small
service area size to
reduce the query cost.
56
Numerical results (2)
 Kopt vs. σ
 Kopt increases as σ
increases.
 When the mobility
rate is high, the
mobility management
cost is also high. The
proxy likes to stay at
a large service area
to reduce the location
handoff cost
57
Numerical results (3)
 Kopt vs. the sleep ratio.
 Kopt decreases as the
MN sleeps longer.
 Data in MN's local cache
are more likely to be outof-date when the MN
sleeps longer. The MN
will stay close to the
proxy to reduce the
triangular CN-proxy-MN
communication cost
58
Numerical results (4)
 Kopt vs. cache size.
 Kopt decreases as the
number of cached data
objects increases.
 As the cache size
increases, more
invalidation reports will be
sent from the CN to the
MN, given the same
update rate for all data
objects. To reduce the
triangular CN-proxy-MN
cost, the MN tends to
stay closer to the proxy.
59
Performance Comparison
Compare our scheme with three schemes:
 No-proxy no-caching (NPNC) scheme: basic
MIPv6 scheme
 Proxy no-caching (PNC) scheme: proxy-based
regional registration scheme using a proxy for
mobility management.
 No-proxy caching (NPC) management scheme:
cached data objects maintained by the MN for
cache management, no proxy used.
60
Performance Comparison (2)
No-proxy no-caching (NPNC) scheme
proxy no-caching (PNC) scheme
61
Generated Network Traffic as a Function
of λq,i
 Caching based
schemes (NPC and
PICMM) achieve much
better performance,
especially when λq,i is
large.
 NPC or PICMM
increases slowly, PNC
or NPNC increases
drastically.
62
Generated Network Traffic as a Function
of σ
 PICMM scheme
outperforms all other
schemes, especially
better when σ is high.
63
Generated Network Traffic as a Function
of Cache Size
 The total cost
incurred under
PICMM increases as
the number of cached
data items increases.
 Better performance
especially when Ndata
is large because
caching saves much
of the uplink cost for
query processing.
64
Generated Network Traffic as a Function
of μi
 The generated network traffic
in non-caching based scheme
(NPNC or PNC) is insensitive
to μi.
 The generated network traffic
in caching schemes becomes
sensitive to μi. because the
query traffic to the server
depends on if cached data
objects are valid.
 If data are updated frequently,
a caching scheme will not
perform good.
65
Generated Network Traffic as a Function
of ωs/ωw.
 When the sleep ratio is ωs/ωw
extremely large, MN is mostly
sleeping all the time. The
cache is mostly invalid due to
long sleep.
 PICMM would perform worse
than PNC because of the CNproxy-MN triangular cost for
routing query inquiries/replies
and invalidation reports under
PICMM.
 At a reasonable range of sleep
ratio (<2), PICMM outperforms
all other schemes.
66
Publications
 Conferences Paper
 I.R. Chen, W. He, and B. Gu, DMAP: A Scalable and Efficient
Integrated Mobility and Service Management Scheme for Mobile
IPv6 Systems, 2nd IEEE International Workshop on
Performance Management of Wireless and Mobile Networks,
Tempa, FL, November 2006
 Submitted papers
 I.R. Chen, W. He, B. Gu. Proxy-based Regional Registration for
Integrated Mobility and Service Management in Mobile IP
Systems. (Submitted to Computer Journal)
 I.R. Chen, W. He, B. Gu. IMSA-MIPv6: Integrated Mobility and
Service Management Architecture for Mobile IPv6 Systems.
(Submitted to Wireless Personal Communications Journal)
 W. He, I.R. Chen, B. Gu. A Proxy-Based Integrated Cache
Consistency and Mobility Management Scheme for Mobile IP
Systems (Submitted to the IEEE 21st International Conference
on Advanced Information Networking and Applications )
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To be Completed and Future Work
 Evaluate our designs by simulation with ns-2.
 Extend two-level regional registration design to more
than two levels as in HMIPv6 and identify the optimal
level to use to maximize the system performance.
 Investigate context-aware database applications that can
benefit from knowledge of the MN's location and service
context.
 Add fault tolerance and recovery into our designs.
 Experiment with mobile database query applications and
the design of PICMM to decide which it is more
beneficial whether to forward a copy of the data object
instead of an invalidation report to the MN.
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Schedule
Deadline
Research Activity
January, 2005 Surveyed and analyzed existing mobility/service management in
wireless networks.
May, 2005 Studied the characteristic of future all-IP based wireless networks.
September, 2005 Proposed and analyzed IMSA-MIPv4: proxy-based integrated
mobility and service management scheme in Mobile IPv4
systems
January, 2006 Proposed and analyzed IMSA-MIPv6: proxy-based integrated
mobility and service management scheme in Mobile IPv6
systems
April, 2006 Proposed and analyzed DMAP for the case in which ARs can
perform only network-layer functions: DMAP
November, 2006 Proposed and analyzed PICMM for the case in which ARs can
perform application-layer functions allowing proxies to carry
service context information regarding cached data objects for
mobile database applications.
December, 2006 Preliminary exam
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Schedule (continued)
March, 2007 Completion of design and analysis of hierarchical DMAP and
IMSA for MIPv6
June 2007 Completion of design and analysis of fault tolerance and
recovery of DMAP and IMSA for MIPv6
Completion of extension to PICMM to deal with the case that
September, 2007 data objects are forwarded to the MN instead of invalidation
reports for mobile database query applications
Completion of the applicability study by identifying context
November, 2007 aware database applications that can benefit from DMAP and
IMSA designs; completion of algorithm design and analysis
for such applications identified.
December, 2007 Research Defense
Completion of simulation studies based on ns-2 to validate
analytical results as well as to compare DMAP, IMSA and
March, 2008 PICMM and new algorithms extended against basic MIPv6,
MIP-RR, HMIPv6 and other existing algorithms in MIPv6 for
mobility and service management.
May, 2008 Final defense.
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Thank you
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