Transcript mobility management

Mobility Management in Packetbased Communication Networks
Yun Won Chung
Electronics and Telecommunications Research Institute
E-mail: [email protected]
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Contents

Introduction

Mobility management in circuit-based
communication networks

Mobility management in packet-based
communication networks

Mobility management in all-IP networks

Further studies
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Introduction

Mobility management



Location management

Location update (registration)

Call delivery
Handoff management
Tradeoff between location update and call delivery

Signaling load analysis

Resolution of location information (i.e., cell, location area,
service area)
Mobility Management in Circuitbased Communication Networks
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Location Management
Location update
Call delivery
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Network Service Area in 2G Systems
* source: reference [1]
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Location Registration and Call Delivery


Centralized database architecture

Dynamic hierarchical architecture

Per-user location caching

User profile replication

Pointer forwarding

Local anchoring
Distributed database architecture

A fully distributed registration scheme

Partitioning

Database hierarchy
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Location Update and Terminal Paging
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
Location update schemes

Dynamic LA management

Three dynamic update schemes
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Time-based

Movement-based

Distance-based
Terminal paging schemes

Paging under delay constraints

Update and paging under delay constraints
Mobility Management in Packetbased Communication Networks
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Mobile Station State

In circuit-based communication networks


In packet-based communication networks




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MT is in idle or busy state
MS is in Idle, ready, or standby state in GPRS
UE is in PMM-detached, PMM-idle, cell-connected, or URAconnected state in UMTS
Cell, URA, RA, or LA is the unit area for location update
Frequency of location update and paging depend on
the state of MS or UE
Effect of timer (i.e. ready timer, inactivity timer, etc.) is
important
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Network Service Area in GPRS
* source: reference [1]
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GPRS MS State Model

Idle
MS is not reachable
 After attach, the MS moves to
ready state
Ready
 Packet transmission is
possible
 Cell-based location update is
performed
 Ready state can be subdivided into ready(off) and
ready(on)
Standby
 RA-based location update is
performed



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URAs, RAs, and LAs in UMTS
* source: reference [2]
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UMTS UE State Model
MM state model in SGSN
RRC state model in UTRAN
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UMTS UE MM and RRC States
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MM state
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PMM detached

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PMM connected



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Packet switched (PS) signaling connection is established
Serving RNC id is stored
Cell-connected or URA-connected
PMM idle



UE is not reachable
PS signaling connection is released
Only RA information is stored
RRC state

Idle


Cell connected



No RRC connection
Cell level location information is managed
Stays until inactivity timer expires
URA connected

URA level location information is managed
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Research on the Analysis of MS State

Yun Won Chung, Dan Keun Sung, and A. Hamid Aghvami, “Steady State
Analysis of Mobile Station State Transitions for General Packet Radio
Service,” in Proc. PIMRC’2002, pp. 2029 – 2033, Lisbon, Portugal, 2002

Yun Won Chung, Dan Keun Sung, and A. Hamid Aghvami, “Steady State
Analysis of User Equipment State Transitions for Universal Mobile
Telecommunications Systems,” in Proc. PIMRC’2002, pp. 2034 – 2038,
Lisbon, Portugal, 2002

Yun Won Chung and Dan Keun Sung, “Modeling and analysis of
combined mobility management and implicit cell update scheme in
General Packet Radio Service,” in Proc. VTC’2003 Spring, Jeju, Korea,
2003
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Analysis of GPRS MS State

Location update & paging in GPRS

Cell in ready state

RA in standby state

Location update and paging frequencies depend on the state of
MS

Tradeoff between location update and paging signaling based
on the number of cells in an RA
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Derivation of steady state probability of MS
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Performance analysis using steady state probability
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Modified MS State Model
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Exit from Idle

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Ready(off) by Attach (T12)
Exit from Ready(off)

Idle by detach (T21)

Ready(on) by packet session arrival
(T23)
Standby by ready timer expiry (T24)
Exit from Ready(on)

Idle by Detach (T31)

Ready(off) by completion of session
processing (T32)
Exit form Standby

Idle by Detach (T41)

Ready(off) by RA update due to
movement or RA update timer
expiration (T42)

Ready(on) by packet session arrival
(T43)
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Steady State Probability

Stationary probability

Steady state probability
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Numerical Example
P1: idle
P2: ready(off)
P3: ready(on)
P4: standby
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Analysis of UMTS UE State

Location update & paging in UMTS
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Cell in cell-connected state
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URA in URA-connected state

RA in PMM-idle state

Location update and paging frequencies depend on the state of
UE

Derivation of steady state probability of UE

Performance analysis using steady state probability
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Modified UE State Model

Exit from PMM detached

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Cell connected (off) by attach (T12)
Exit from Cell connected (off)

PMM detached by detach (T21)

Cell connected (on) by packet session arrival
(T23)

URA connected by inactivity timer expiry (T24)
Exit from Cell connected (on)

PMM detached by detach (T31)

Cell connected (off) by completion of session
processing (T32)
Exit form URA connected

PMM detached by detach (T41)

Cell connected (off) by URA update (T42)

Cell connected (on) by packet session arrival
(T43)

PMM idle by URA update timer expiration (T45)
Exit from PMM idle

Detach request (T51)

RA update due to movement of a UE or
expiration of an RA update timer (T52)

Incoming or outgoing session arrival (T53)
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Numerical Example
P1: PMM detached
P2: cell connected(off)
P3: cell connected(on)
P4: URA connected
P5: PMM idle
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Combined Mobility Management
* source: reference [1]
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Combined Mobility Management



Location Update
 Based on LA in GSM
 Based on cell or RA in GPRS
 Size of LA > size of RA
Paging
 Based on paging area (= LA or RA)
Combined Mobility Management

Class-A mode MS
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Attached to both GSM and GPRS
Supports simultaneous operation of GPRS and GSM services
Gs interface between SGSN and MSC/VLR
Combined RA/LA update using one radio signaling message
Circuit-switched paging via SGSN to either RA or cell based on a
GPRS MS state
Efficient management of GSM/GPRS MM
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Combined Mobility Management

Implicit cell update




The location of MS is known to network if GSM MS is in busy
state
How can we utilize this cell-based location information for
Class-A GPRS MS state management?
After the implicit cell update, paging only one cell may be
sufficient for call or packet delivery if the cell location is
managed
A new MS state model


Incorporation of GSM MS state into GPRS MS state
Ready state can be sub-divided into ready(off), ready(on)GSM, ready(on)-GPRS, ready(on)-GSM/GPRS
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Modified MS State Model
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Numerical Examples
Mobility Management in
All-IP Networks
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Micro-Mobility Protocols

Cellular IP
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HAWAII
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Regional registration
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Hierarchical Mobile IP
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Fast handoff
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Seamoby Activities
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RFC 2132: dormant mode host alerting (“IP paging”)
problem statement

RFC 3154: requirements and functional architecture for
an IP host alerting protocol
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MH state
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Active
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Dormant
Functional entities
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Paging agent
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Tracking agent
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Dormant monitoring agent
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Motivation of IP Paging

Consider an MH, which is moving fast and is not involved in a
communication




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Optimization for nodes that are currently not in a session might be
taken into consideration
Entering dormant mode

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Bandwidth consumption
Processing power
Protocol states
Avoids frequent location update
Decreases the preciseness of the network’s knowledge about
individual mobile’s location to paging areas
Dormant mode supports
 saving scarce radio bandwidth
 cutting superfluous location updating
 reducing battery energy drainage
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P-MIP (an Idle MN’s Movement)
HA
Reg request
PA1
Reg reply
FA
MN
PA2
* source: reference [3]
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P-MIP (Page an Idle MN)
HA
CN
MN
FA
data
paging
reg
* source: reference [3]
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Analysis of P-MIP MS State


Yun Won Chung, Dan Keun Sung, and A. Hamid Aghvami, “Steady State
Analysis of P-MIP Mobility Management,” IEEE Communications Letters,
June 2003
P-MIP MS State

Active

Idle
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Numerical Examples
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Further Studies

Multicast accommodating host mobility
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Power saving MM algorithm
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Vertical handoff
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Mobility support in WLAN
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Network mobility
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Integrated MM in heterogeneous all-IP networks
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References
1.
Brahim Ghribi and Luigi Logrippo, “Understanding GPRS: the GSM
packet radio service,” Computer Networks, vol. 34, pp. 763-779, 2000.
2.
Yi-Bing Lin, Yieh-Ran Haung, Yuan-Kai Chen, and Imrich Chlamtac,
“Mobility management: from GPRS to UMTS,” Wireless Communications
and Mobile Computing, vol. 1, pp. 339-359, 2001.
3.
Xiaowei Zhang, “Paging in Mobile IP”, presentation material on the 4th
International Workshop on Wireless Mobile Multimedia, Rome, Italy, July
2001, http://www.comet.columbia.edu/~xzhang/pmip/
4.
I. F. Akyildiz, et al., Mobility management in next-generation systems,
Proceedings of the IEEE, vol. 87, no. 8, Aug. pp. 1347 – 1384, 1999.
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Any Questions & Comments ?