Handover Management In Integrated Wlan And Mobile Wimax

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HANDOVER MANAGEMENT IN INTEGRATED WLAN AND MOBILE WIMAX NETWORKS

Pradeep Thomas Thundiyil

M.Tech 2nd Sem

DCN

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Overview

WLAN and WMAN: Integration.

Mobility Management and Integration Solutions For Heterogeneous All-IP Wireless Networks.

Mixed Network Client Use Case.

Handover Between WIMAX and WIFIUsing MIH Framework.

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Need for Integration

Ubiquitous Coverage.

Broadband Connectivity.

Quality Of Service.

Economical.

WLAN

WiMAX

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Mixed Wi Fi and WiMAX

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Handoff

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Types of Handovers

• Homogeneous (Horizontal) Handovers• Within Single Network (Localized Mobility)• Limited opportunities

• Heterogeneous (Vertical) Handovers• Across Different Networks (Global Mobility)• More Opportunistic

• IEEE 802.21 is primarily for Vertical Handovers

….can also be used for Homogeneous Handovers

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Overview





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Integration Solutions

IETF

SIP (Application)

mSCTP

(Transport)

MIP(Network)

3GPP

VCC/IMS

LTE/SAE

IEEE

IEEE 802.21 (MIH)

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Mobility Management

• MIP provides a new IP address to a mobile node as it moves to a new network.

In MIPv4 the correspondent node (CN) sends packet to the MN through the MN’s HA – longer route.

MIPv6 allows CN to send packets directly to the FA at the visited network – reduced delay. In L3 Handover the disruption due to long delays is minimized using Fast handover MIP (FMIP).

IETF Solutions: Upper Layer Protocols

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IETF Solutions: Upper Layer Protocols

• Network Layer MIP

• Transport Layer mSCTP

• Application Layer SIP

• SIP is an application layer signaling protocol:– Widely used for setting up and tearing down

multimedia sessions.

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3GPP Solutions

• 3GPP defined a mobility management scheme based on IMS.

• VCC/IMS integrates UMTS and unlicensed spectrum technologies (Wi-Fi).

• SAE/LTE System Architecture Evolution/ Long term Evolution (efficient Vertical Handover).

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Scope of 802.21

Handover Initiation

Handover Preparation

Handover Execution

Search New Link

Network DiscoveryNetwork SelectionHandover Negotiation

Setup New Link

Layer 2 ConnectivityIP Connectivity

Transfer Connection

Handover SignalingPacket Reception

IEEE 802.21 helps with Handover Initiation, Network Selection and Interface Activation

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What IEEE 802.21Defines

• The current specification includes a Media Independent Handover Function (MIHF) consisting of three basic services – Media Independent Event Service (MIES)– Media Independent Command Service (MICS), and – Media Independent Information Service (MIIS)

• MIH aims to help and enhance the operation of mobility management protocols.

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• Media Independent Handover Services is an IEEE (802.21) working on a specification that facilitates handover optimization between heterogeneous access networks by providing – Link layer intelligence and – Network information to upper layers

• Support for multiple access technologies (e.g., IEEE and non-IEEE access technology)

• Support for both network and device initiated handovers

What is Media Independent Handover ?

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Media Independent Event Service (MIES)

• Events may originate from MAC, PHY or MIH Function either at the mobile node or at the network.

•The source of these events may be either local or remote.

•Two types of Event Service –Link Events and –MIH Events.

MIH User (L3 and above)

MIHF

Lower Layers (L2 and below)

MIH Event s

Link Event s

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MIH Events MIH Event MIH Event Type Description

MIH_Link_Up State Change L2 connection is established and link is available for use

MIH_Link_Down State Change L2 connection is broken and link is not available for use

MIH_Link_Going_ Down

Predictive Link conditions are degrading & connection loss is imminent

MIH Link_ Handover_ Imminent

Link Synchronous L2 handover is imminent based on changes in link conditions

MIH Link_Parameters-Report

Link Parameters Link parameters have crossed specified threshold and need to be reported

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Media Independent Command Service (MICS)

• Media Independent Command Service refers to the commands sent from the higher layers to the lower layers in the reference model

• Two types of Command Service –MIH Commands –Link Commands

MIH Users (L3 and above)

MIHF

Lower Layers (L2 and below)

MIH Commands

Link Commands

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MIH Commands

MIH Command Comments

MIH_Scan Scan a list of links

MIH_Net_HO_Candidate_Query Network may initiate handover and send a list of suggested networks and associated point of attachments (POA)

MIH_Net_HO_Commit Network commits to do the handover and sends the choice of selected network and associated POA

MIH_N2N_HO_Query_Resources This command is sent by serving MIHF entity to target MIHF entity to allow for resource query and handover preparation.

MIH_MN_HO_Complete Notification from MIHF of the MN to target MIHF indicating handover completion

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IEEE 802.21 Standard - Media Independent Handover (MIH) framework

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Overview





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3G WWAN

MxN – Mixed-Network Client Use Case

Home

Airport

Zone 1 Zone 2 Zone 3

Zone 4 Zone 5 Zone 6

Zone 7 Zone 9WiMAX Zone 8 WiMAX

Radio StateRadio State

3G WWAN

Wi-Fi

WiMAX

GPS


3G WWAN

Wi-Fi

WiMAX

GPS


3G WWAN

Wi-Fi

WiMAX

GPS


3G WWAN

Wi-Fi

WiMAX

GPS


3G WWAN

Wi-Fi

WiMAX

GPS


3G WWAN

Wi-Fi

WiMAX

GPS


3G WWAN

Wi-Fi

WiMAX

GPS

IEEE 802.21 for Network DiscoveryIEEE 802.21, SIP, VCC, IMS, for Network Selection and Service Continuity across multiple radios (3G WWAN Wi-Fi WiMAX)802.21, SIP, IMS for Service Continuity (Wi-Fi WiMAX)VCC, SIP, IMS for Call Continuity (3G WWAN Wi-Fi)

Plug into power jack Wakeup Wi-FiContinue over Wi-Fi

Wi-Fi Link Going Down.

Operator initiated switch to WiMAXContinue session on WiMAXShutdown Wi-Fi

Connect to Wi-Fi

Battery level lowShutdown WiMAXSwitch to 3G WWAN

Wakeup Wi-Fi

Continue session on Wi-Fi

Operating on 3G WWAN

Continue session on 3G WWAN

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Overview





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Mobile Node

Current WiMAX BS

Candidate Wi-FI AP

Candidate Wi-Fi AP

MIIS

1MN becomes aware of new connectivity opportunities through beacons received from candidate APs. Alternatively, it can also periodically query the MIIS to gather information on available access networks.

MIH_Get_Information Request

MIH_Get_Information Response

MIH_N2N_HO_Candidate_Query Request

MIH_N2N_HO_Query_Resource Request

MIH_N2N_HO_Query_Resource Request

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3MIH_N2N_HO_Query_Resource Response

MIH_N2N_HO_Candidate_Query Request

Always best connected scenario: WiMAX/WiFi handover using the MIH framework.

MIHMN_Handover_Complete Response

Mobile Node

Current WiMAX BS

Candidate Wi-FI AP

Candidate Wi-Fi AP

MIIS

4 Handover decision based on resource availability and user’s preferences. Selection of the target network.

MIH_N2N_Handover_Commit Request

MIH_MN_Handover_Commit request

MIH_N2N_Handover_Commit Response

MIH_MN_Handover_Commit response

(FMIPv6) HAck, FBAck

(Wi-FI) ASSOCIATION PROCEDURE

(WiMAX) DISSASSOCIATION_PROCEDURE

MIH_MN_Handover_Complete Request

Always best connected scenario: WiMAX/WiFi handover using the MIH framework.

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Conclusion & Future Directions

• The integration of heterogeneous networks seems to be a good approach in order to offer the 4G always best connected vision.

• The use of the MIH framework for integrating WiFi and WiMAX networks provides seamless handover.

• MIH support for multihop heterogeneous networks, QoS mapping, and resource allocation mechanisms for WLAN/WMAN integrated networks, and security solutions are to be improved.

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References

• G. Lampropoulos, A. Salkintzis, and N. Passas, “Media Independent Handover for Seamless Service Provision in Heterogeneous Networks,” IEEE Commun. Mag., vol. 46, no. 1, Jan. 2008.

• Kejie Lu, Yi Qian, Hsiao-Hwa Chen, “ A Secure and Service-

Oriented Network Control Framework for WiMAX Networks,” IEEE Communications Magazine, May 2007.

• Ian F Amine M. Houyou, Hermann De Meer, Moritz Esterhazy,

“P2P-based Mobility Management for Heterogeneous Wireless Networks and Mesh Networks”.

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Thank you for your attention..!

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Handover Management In Integrated Wlan And Mobile Wimax