Transcript Document

A seamless handover between
cdma2000 and WLAN for
3G-WLAN interworking service
continuity
指導教授:黃培壝
學生:陳鵬宇
Outline
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Introduction
Overview of Interworking
Architecture among Heterogeneous
Networks
Development of Mobile Controlled
handover algorithm
Results of Simulation
Conclusion
Introduction
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WLAN and cdma2000 that based on packet
switch are one of the technologies being used
most frequently.
Interworking of two technologies will bring
the user a drastic increase of wireless service
performance.
To perform effective services under
interworking environments
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protocol authentification technology
intelligent resource management algorithm
varied handover technologies
Introduction
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In this paper, we focus on soft handover
algorithm that initiated by the terminal
between WLAN and cdma2000, seamless
data transmission, and also on maintaining
service continuity.
Overview of Interworking Architecture
among Heterogeneous Networks
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In Figure 1 a), a varied networks already
existed exchange packet data using
interworking service server (ISS).
Overview of Interworking Architecture
among Heterogeneous Networks
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In Figure 1 b), a varied networks already
existed exchange packet data through IP
network.
Overview of Interworking Architecture among
Heterogeneous Networks - Configuration of
cdma2000 and WLAN
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We constitute heterogeneous networks using
cdma2000, WLAN and LAN.
In case terminal moves between
WLAN and cdma2000, we think
about soft handover method that
controlled by terminal by
seamless connection control
(SCC) scheme.
Overview of Interworking Architecture among
Heterogeneous Networks – TCP/IP
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TCP consists of 4 layers as shown in Figure 3.
Overview of Interworking Architecture among
Heterogeneous Networks – TCP/IP
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The cdma2000 can set up channel using two
paths. One is connected remotely by using
modem and dialup line.
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Point to Point Protocol (PPP)
InterWorking Function (IWF)
IWF provides such functions as protocol
change and data transformation in order to
use data network access by using telephone
line like Remote Access Server (RAS).
Another one is the case that uses Packet
Data Serving Node (PDSN).
Overview of Interworking Architecture among
Heterogeneous Networks - WLAN
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IEEE 802.11x technical standard is a
modulation method in terms of Wireless LAN
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Direct Sequence (DS)
Frequency Hopping (FH)
In order to access to IP network using WLAN,
hot spot method, specifically, a system
configuration like public wireless LAN method
is used.
Overview of Interworking Architecture among
Heterogeneous Networks – CDMA2000
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CDMA200 is the third generation technology
of IS-95.
And to provide mobility service at IP level, it
uses Mobile IP(MIP) and Authentication,
Authorization, Account (AAA).
Packet Data Service Node (PDSN) is a device
that enables user to provide packet data
service at Base Station Controller (BSC).
Overview of Interworking Architecture among
Heterogeneous Networks – CDMA2000
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Mobile terminal and PDSN are connected by
using Point-to-Point Protocol (PPP) and after
connected, it is transformed into IP.
If handover occurs between BS and BS, there
will be established location updating of HA by
MIP.
Quality of Service (QoS) uses a mode of
managing priority of packet employing
Differentiated Service (Diffserv).
Overview of Interworking Architecture among
Heterogeneous Networks – CDMA2000
Overview of Interworking Architecture among
Heterogeneous Networks – CDMA2000
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Mobile terminal can set up channel up to the
server placed in the particular location by
using largely 3 types of path.
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PDSN
IWF
RAS
In all three cases, it is connected to terminal
by using PPP, and then after, it will be
changed into IP.
Overview of Interworking Architecture among
Heterogeneous Networks – CDMA2000
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PDSN can be provided the best possible
transmission performance.
IWF provides protocol and data
transformation in order to perform
interworking between networks of different
kinds.
Development of Mobile Controlled
handover algorithm
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Two types of handover have been displayed.
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Network Controlled (NC) Handover
Mobile Controlled (MC) Handover
In MC Handover, however, terminal
recognizes changes of wireless service
network range by using signal strength of
access node of network and also terminal
move.
In previous chapter, we have mentioned that
we will consider Seamless Connection Control
(SCC) only between WLAN and cdma2000.
Development of Mobile Controlled
handover algorithm
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The soft handover developed this
time maintains channel at border
area between WLAN and cdma2000.
Home site of terminal updates
information of terminal, and this
method is called "Active Update."
Taking other case like Passive Update,
there occurs information updating
only when network system requests
terminal for information updating.
Development of Mobile Controlled
handover algorithm
Results of Simulation
Results of Simulation
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We used PDA as for terminal. PDA was
equipped with CDMA and WLAN modem.
To test data transmission, server listens to
mp3 music file that stored in PDA. At this
time, user produces handover by moving PDA.
We used hard handover (H.HO) and soft
handover (S.HO) based on MC Handover.
Results of Simulation
Results of Simulation
Results of Simulation
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Figure 7 displays measurement of HA
updating signals according to handover.
Results of Simulation
S.O.
Conclusion
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MC Handover sets up channel actively at
terminal, and transmits handover signals to
destination server.
Soft handover maintained data transmission
regardless handover by using each channel
between WLAN and cdma2000.
MC soft handover can be used as a seamless
connection control method that enables us to
provide critical status for data transmission.