mobile network - postechdpnm.postech.ac.kr/eece702/kt/3.pdf · 2007-09-17 · 18 postech mobile...

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Mobile Network

Eun Kyoung PAIK

Sep. 17, 2007

Future Technology Lab., KT

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ContentsIntroduction

Brief Review of Internet and Mobility

Advanced IP Mobility

Standardization in IETF

Make It Real: IP Mobility and WiBro

Future Mobile Networks

Conclusion and Perspectives on Future Research

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Why IP Mobility ? Emerging Wireless Technologies

Demand for Interconnecting Heterogeneous Networks

Independent from Low layer Wireless Technologies

Common Mobility Support for all access networks

All-IP Convergence

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Where are we now ?Network

Circuit-Based Telephone Network

Packet-Based Internet

Future Network

Mobile Communication1G Analog

2G Digital (문자)

3G High Speed (영상)

4G All-IP (고속멀티미디어)

Mobile Internet (IP Mobility)

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Two Functions of IP AddressIdentification

Location

IP (Internet Protocol)

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Mobility: demand for changeable location

Identity: demand for unchangeable identification

How to handle changeable characteristics and unchangeable characteristics all at once ?

IP and Mobility

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Basic Concept of IP MobilityEach Mobile Node (MN) maintains two IP addresses

Address1 for identification

Address 2 for location

The Address for Identification is maintained even though the MN moves

The Address for Location is changed whenever the MN moves

Adding Mobility to IP

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Mobile IPv4Two IP Addresses

Home Address (HoA): for Identification

Care-of Address (CoA): for Location

FA CoA

Co-located CoA

Foreign Agent (FA)CoA Allocation

Home Agent (HA)HoA-CoA Binding

Internet

CN

FA

MNMN

2

3

44

CoA registration

HoA-CoA binding

CoA

HoA MN’s HA

moving

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MN: Mobile NodeCN: Correspondent Node

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Mobile IPv4 and Address ProblemIP Address Management in Mobile IPv4 for Location

FA (Foreign Agent) CoA: using FA’s address

Collocated CoA: using DHCP

IP Address Problem in Mobile IPv4Lack of IPv4 Address Space

Difficult for allocating 2 addresses per MN

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IPv6 Address SpaceIPv4 Address Space = 232 = 4,200,000,000

IPv6 Address Space = 2128 = 340,282,366,920,938,463,463,374,607,431,768,211,456

IPv6 Address Space per 1m2 on earth = 665,570,793,348,866,943,898,599

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IPv6: Additional BenefitsVast Address Space

Auto-configuration

Plug-and-Play

Consider Mobility, Security from scratch

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IPv6 Stateless AutoconfigurationIn each subnet, Router advertisement (RA) with subnet Prefix information

At each node, Autoconfiguration by combining this Prefix

Between nodes, Duplicated Address Detection (DAD) for uniqueness

Router

Node

A::1DAD

RA

A::

Node

A::2

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Text Representation of Addresses“preferred” form: 1080:0:FF:0:8:800:200C:417A

compressed form: FF01:0:0:0:0:0:0:43

FF01::43

address prefix: 1080:0:FF:0::/64

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Mobile IPv6FA is eliminated

By Autoconfiguration

IPv6 is designed with Mobility support in mind

Route Optimization (RO)

Security

Internet

CN

Router in Foreign link

MNMN

2

3

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CoA registration

HoA A::1

MN’s HA

moving

CoA registration

CoA C::111

55

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Mobile IPv6: Route Optimization

Home Network (Home Agent)

Network (Correspondent Host)

Visited Network B (Mobile Host)

Visited Network A (Mobile Host)

First Packet

First Packet

Handoff

Subsequent Packets

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Mobile IPv4 vs. Mobile IPv6

Integrated support for route optimizationRoute optimization via separate protocol specification

Routing to mobile node via tunneling and source routing

Routing to mobile nodes via tunneling

Authenticated notification of home agent and other correspondents

Authenticated registration with home agent

Router DiscoveryAgent Discovery

Care-of address obtained via Stateless Address Autoconfiguration, DHCP, or manually

Care-of Address obtained via Agent Discovery, DHCP, or manually

Collocated care-of addressA “plain” IPv6 router on the foreign link (foreign agent no longer exists)

Foreign Agent

SameMobile node, Home Agent, Foreign link

Equivalent Mobile IPv6 ConceptMobile IPv4 Concept

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Network Mobility: TerminologyNetwork Mobility (NEMO)

Mobile Network

(NEtwork in MOtion, NEMO)

Mobile Router (MR)

Mobile Network Prefix (MNP)

Mobile Network Node (MNN)Local Fixed Node (LFN)

Local Mobile Node (LMN)

Visiting Mobile Node (VMN)

Home Agent (HA)

MNP A::

AR

HA

MNNs

Core IP network

MR

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Network Mobility: Basic Support Two Interfaces

Egress Interface

MR’s CoA configuration

(as MN)Ingress Interface

MNP advertisement

(as Router)

Two BindingsHoA-CoA BU for MR itself

MNP-CoA BU for MNNs

HA-MR bidirectional tunnel

Mobility Transparency

Internet

MR

MR’s HA

Mobile Network

Binding Update

AR

Tunneling

MNNs

CN

MNP-CoA binding

CoA C::1

MNP A:B::/64

HoA A::1

moving

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Mobile IP Issues

Mobile IP is not ready for deployment ?

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Seamless IP MobilityWhat is Seamless Mobility ?

QoS guarantee over Mobility

Reducing handover delay

Reducing data loss

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Fast HandoverFast handover : Reduce handover latency

Hanover Latency: a period during which the Mobile Node is unable to send or receive packets because of link switching delay and IP protocol operations

Movement detection

New Care of Address configuration

Binding Update

Fast Handovers for Mobile IPv6 (RFC 4068)Predictive mode

Reactive mode

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Predictive Fast Handover

P1::/64

PARNAR

moving

PAR: Previous Access RouterNAR: New Access RouterFBU: Fast Binding UpdateHI: Handover Initiate

Internet

CN

MN

FBU

HI

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Reactive Fast Handover

PARNAR

moving

PAR: Previous Access RouterNAR: New Access RouterFBU: Fast Binding UpdateFNA: Fast Neighbor Advertisement

Internet

CN

MN

FNA

FBU

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Fast Handover Issues

Is FMIP6 enough for seamless handover ?

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Hierarchical MobilityHMIPv6

Mobility Anchor Point (MAP)

Two Addresses

On link Care-of Address (LCoA) : Based on AR’s prefix

Regional Care-of Address (RCoA) : Based on MAP’s prefix

MAP

HACN

Internet

MAP

OldAR

NewAR

MAP domain

MN

BU

(HoA, RCOA)

(RCoA, LCoA)

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Multihoming: DefinitionMultiple access to the Internet

Mobile Node listens Multiple Prefixes

Mobile Node has Multiple Addresses

Mobile Node has Multiple Interfaces

Link1 Link2Prefix A:: Prefix B::

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Multihoming: Goals and BenefitsBenefitsGoals

Load sharing Load balancingPreference settingAggregatebandwidth

Quantity Quality

Load

Ubiquitous accessFault- recoveryBicasting (n-casting)

SpaceTimeAccess technology

Session

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Multihoming Configurations with MN

Fixed node,

Mobile node (HoA as CoA)

0n

nn

Visited Network is multihomed

n1

n HAs1n

n interfaces11

CasesNumber of CoAsNumber of HoAs

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Multihoming Configurations with NEMO(x,y,z) notification

Multiple MRs

Multiple HAs

Multiple Prefixes

8 configurations

- (1,1,1)

- (1,1,n)

- (1,n,1)

- (1,n,n)

- (n,1,1)

- (n,1,n)

- (1,1,n)

- (n,n,n)

Internet

MR1

HA1

NEMOmoving

MR2

A:: B::

Tunneling

HA2

MNNMNNMNN

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Multihoming for Seamless Mobility

PARNAR

moving

PAR: Previous Access RouterNAR: New Access Router

Internet

CN

MN

PAR Failure Recovery by NAR Association

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Multihoming Issues for Seamless HandoverFailure Detection

On the currently used path

Path Exploration On the alternative paths, Identify an Available path

Path SelectionFrom available paths

Re-homingDivert the existing communications from one path to the other path

Ref. C. Ng, E. Paik, T. Ernst, and M. Bagnulo, “Analysis of Multihoming in Network Mobility Support ,” IETF I-D.

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Failure DetectionOn the MN's side

Router advertisement (RA) from access routers

Layer-2 trigger mechanisms

On the HA's sideHeartbeat signals between MN and HA(s)

e.g., Reduce Binding update interval

(Emulate Tunnel Heartbeat)

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Path ExplorationMN’s Detection for Available Network Media

Layer 2 Triggers

Detecting Network Attachment (DNA)

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Path SelectionBy HA

Based on information in Binding cache

By MRBased on router advertisements for Multiple MRs

By MNNBased on "Default Router Selection“ for Multiple MRs

Based on "Source Address Selection“ for Multiple Prefixes

By User or Applicatione.g., When users want to select a particular access technology

By Hybrid mechanismCombination of any of the above

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Re-HomingMH or Single Prefixed MR

Exchange of additional BU messages

Multiple Prefixed MRAdditional Requirement for End to End mechanisms

Some form of end to end signaling, Or

Using different addresses for the communication

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Network-based Mobility ManagementNETLMM WG Motivation

Develop a protocol between the LMAs and MAGs that handles

A new MN that powers on or moves from another LMM domainAn existing MN that shuts down without any noticeRouting update when a MN moves from one LMA to another within the LMM domain

Current FocusProxy Mobile IP

NetLMM Domain

LMA1 LMA2

MN@LMA1 MN@LMA2

MAGMAG

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Advent of New Access NetworksIEEE 802.16 PMP Link layer (WiMAX)

No native bi-directional multicast support

No direct communication between Subscriber Stations

Connections always between SS and BS

48-bit MAC addresses are not used for transmission

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IssuesNew Mobility Paradigm ?

Cross Layer Optimization

Global/Local Mobility

Host Identification

AAA (Authentication, Authorization, Accounting)

…

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IETFInternet Engineering Task Force

Standardize Internet Protocols

IETF (Engineering) and IRTF (Research)

Process (RFC 2026)Internet Draft (Individual/ WG) RFC (Request For Comments)

Standard track

Nonstandard track– Informational RFC

– Experimental RFC

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Mobility-related Working Groups in IETF (I)Internet Area

MIP4 (Mobility for IPv4) WG

MIP6 (Mobility for IPv6) WG

NEMO (Network Mobility) WG

MIPSHOP (MIPv6 Signaling and Handoff Optimization) WG

MONAMI6 (Mobile Nodes and Multiple Interfaces in IPv6) WG

6LOWPAN (IPv6 over Low power WPAN) WG

16NG (IP over IEEE 802.16 Networks) WG

NETLMM (Network-based Localized Mobility Management) WG

DNA (Detecting Network Attachment) WG

HIP (Host Identity Protocol) WG

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Mobility-related WGs in IETF (II)Routing Area

MANET (Mobile Ad-hoc Networks) WG

Security AreaMOBIKE (IKEv2 Mobility and Multihoming) WG

Operations and Management Area CAPWAP (Control And Provisioning of Wireless Access Points) WG

Application Area GEOPRIV (Geographic Location/Privacy) WG

IRTFMOBOPTS (IP Mobility Optimizations) Research Group

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IP Mobility in IETFHost Mobility and Network Mobility

Host Mobility (in MIP4/MIP6 WG)

Mobile IP (RFC 3220)

Mobile IPv6 (RFC 3775)

Network Mobility (in NEMO WG)

NEMO Basic Support (RFC 3963)

Host-based Mobility and Network-based MobilityHost-based Mobility: Mobile IP (in MIP4/MIP6 WG)

Network-based Mobility: Proxy Mobile IP (in NETLMM WG)

NETLMM: Network-based Localized Mobility Management

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IP Mobility Enhancement/Extensions in IETFHierarchical Mobile IP (in MIPSHOP WG)

Fast Mobile IP (in MIPSHOP WG)

Multihoming (in MONAMI6 WG)

MIPSHOP: MIPv6 Signaling and Handoff Optimization

MONAMI6: MObile Nodes And Multiple Interfaces in IPv6

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Vertical Handover by IETF SolutionInter-technology Mobility (Macro Mobility)

Mobile IPv6 (RFC 3775)

IP Mobility Management for Vertical Handover

Cf. Intra-technology Mobility (Micro Mobility)e.g., Hierarchical Mobile IPv6 (RFC 4140)

Introducing Mobility Anchor Point (MAP)

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IETF MIP6 WGEnhance IPv6 mobility for wide-scale deployments

HA reliability

Deployment and transition issues in IPv4/IPv6 networks

Bootstrapping

Service Selection for MIP6

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IETF NEMO WGRequirements

Car

Aviation

PAN

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IETF MIPSHOP WGMIPSHOP (MIPv6 Signaling and Handoff Optimization) WG

Fast Handovers for Mobile IPv6

FMIP6 for 3G CDMA Networks

FMIP6 on Point-to-Point links

HMIPv6 update

Handover Keys using AAA

PMIPv6 Route Optimization Protocol

MIH (Media Independent Handover) Design Team

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MIPSHOP: MIH Design TeamTradeoffs depending on priority scenarios, flexibility, simplicity and so on

The List of Issues The Layer Split

Node Discovery and Message Routing

Security and Resilience

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IETF MONAMI6 WGSimultaneous Use of Multiple Addresses for

Mobile Hosts (Mobile IPv6)

Mobile Routers (NEMO)

Variants (FMIPv6, HMIPv6, etc)

WG DeliverablesMotivations [Informational]

Problem Statement [Informational]

Registration of Multiple Care-of Addresses [Standard Track]

"Flow/binding policies exchange" solution [Standard Track]

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IETF NETLMM WGPMIP6

PMIP6-MIP6 Interactions

IPv6 Support in NetLMM

IPv4 Support in NetLMM

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NETLMM: MIP and PMIPMIP Proxy MIP

PMA(Proxy Mobile Agent)

HA

Route Update

Movement Movement

HA

Route Update

AR

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IETF 16NG WG16ng (IEEE 802.16 Next Generation)

IP over IEEE 802.16 Networks

Solving basic IP operation over IP CS and Ethernet CS under considering distinctive 802.16 PMP link characteristics

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IETF PerspectivesMEXT (Mobility EXTensions for IPv6) WG will merge following 3 WGs:

MIP6

NEMO

MONAMI6

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IETF MEXT WG CharterEnhance base IPv6 mobility

Consider wide-scale deployments and specific deployment scenarios

Issues identified by implementation and interoperability experience

Produce informational documentatione.g., Design rationale documents or description of specific issues within the protocol.

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MEXT: Deployment Considerations IPv4-IPv6 Dual-stack operation

Multiple interfaces in mobile nodes

High-availability home agents (Reliability)

Employ Mobile IPv6 in the presence of firewalls

Route optimization of network mobility for automotive and aviation communities

AAA for bootstrapping.

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MEXT: Base Specification MaintenanceIssue lists that are generated on the basis of implementation and interoperability experience

Update the IANA considerations of RFC 3775To allow extensions for experimental purposes as well passing ofoptional vendor-specific information

Finish WG documents that are currently in process, and submit for RFC

Prefix delegation protocol mechanism for network mobility

A MIB for NEMO Basic Support

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MEXT: Information DocumentsDesign rationale that documents the historical thinking behind the introduction of an alternative security mechanism, the Authentication Protocol (RFC 4285).

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IETF Mobility IssuesDeployment

Security

Scalability

Reliability

…

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WiBro: TerminologyPortable Internet

“Portable Internet” was named as WiBro (End of April, 2004)

WiBro ServiceAs the name of WiBro is known to the world, it is registered as the name of TTA standard (2006) as well as the name Service

WiBro Standard

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WiBro OverviewProperties of WiBro

High Data Rate MobilityFull Coverage Low Cost

WiBro networkACR

RAS

PSS

IP NetworkIP NetworkInternetInternet

E R E R

ACR

L2 Switch

RAS

MS

DHCP

AAA

ACR ACR

DNSNMS

IP NetworkIP NetworkInternetInternet

E R E R

ACR

L2 Switch

RAS

MS

DHCP

AAA

ACRACR ACRACR

DNSNMS

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WiBro Components (I)ACR (Access Control Router)

A generalized equipment set providing connectivity between RAS and IP network defined for WiBro in TTA.

An ACR provides function of first hop router to PSS.

A part of base station in IEEE 802.16.

RAS (Radio Access Station)A generalized equipment set providing connectivity between mobile stations and ACR defined for WiBro in TTA.

A RAS provides function of attachment point to PSS.

A part of base station in IEEE 802.16.

The RAS is defined as a base station in WiMAX Forum.

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WiBro Components (II)PSS (Portable Subscriber Station)

A generalized equipment set providing connectivity between subscriber equipment and a base station.

It is generally accepted for fixed terminal with IEEE compliant interface that defined by IEEE 802.16.

The PSS can be either fixed station or mobile station.

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WiBro StandardWiMAX Forum standardizes Mobile/Portable/Normadic/Fixed WiMAX

TTA WiBro fits Mobile WiMAX

IP(v6) over WiBro is standardized in TTA IPv6 PG (WiBro6 WG)

IPv6 over IEEE 802.16 is standardized in IETF 16ng WG

IPv6 is specified by WiMAX Forum NWG

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IEEE 802 Wireless WGs

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WiBro Attributes (I)High Data Rate

Maximize sector/user throughput

Broad bandwidth

MAC (Medium Access Control) & RRC (Radio Resource Control)

MobilityVehicular speed mobility (~60km/h)

Seamless service

Longer battery usage

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WiBro Attributes (II)Full Coverage

Various types of cell (Macro / Micro / Pico)

Easy cell planning

Roaming with cellular & WLAN

Low CostImprove spectral efficiency

Reduce infra cost

Multiplexing gain of packet data

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WiBro Requirements (I)Mobility

Vehicular speed mobility ( ~ 60km/h)

Continuous IP seamless service

Handoff break time < 150 msec

Data Rate per UserPeak Data Rate : DL 3Mbps, UL 1Mbps

Cell Edge Data Rate : DL 512Kbps, UL 128Kbps

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WiBro Requirements (II)Service Coverage

Macro(1Km), Micro(400m), Pico(100m)

RoamingSeamless Roaming with Cellular, WLAN system

AirSpectral Efficiency (Average): (DL,UL) (2, 1) bps/Hz/cell

Frequency Reuse Factor = 1

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WiBro LayeringCS

DL(BS), UL(SS): Classifying SDUs to CID

Payload header suppression

MAC CPS

Bandwidth allocation

Connection establishment

Connection maintenance

Quality of Service (QoS)

Scheduling of data over the PHY

Privacy sublayer

Providing authentication

Secure key exchange

Encryption

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WiBro Physical LayerWiBro PHY Properties

Frequency Band : 2.3GHz (Korea)

Cell Coverage : ~1km

Maximum Data Rate (User throughput): DL : 3 Mbps, UL :1 Mbps

WiBro PHY is optimized withMultiple Access : TDD-OFDMA

Modulation : QPSK, 16QAM, 64QAM

Channel Coding : CTC

Flexibility, Scalability, Efficient Resource Usage

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WiBro MAC LayerWiBro MAC Supports flexible QoS

rtPS (real-time Polling Service)nrtPS (non-real-time Polling Service)BE (Best Effort)

MAC layer Service is identified by Connection ID (CID)

An implementation of 802.16 can support multiple CS types, but WiBro focuses on IP CS

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WiBro Network Layer

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Network Reference Model of WiMAX

Internet

• ASN: Access Service Network• CSN: Connectivity Service Network• NAP: Network Access Provider• NSP: Network Service Provider

• BS: Base Station• FA: Foreign Agent• HA: Home Agent• AAA: Authentication, Authorization, Accounting

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ASN Profiles (By WiMAX Forum NWG Spec. Rel. 1)Profile A

Separate BS and ASN GW in separate platforms through R6 interface

Split RRM (Radio Resource Management): RRA in BS and RRC (Radio Resource Controller) in ASN-GW

Profile BCombine BS and ASN GW functionalities (implemented in a single platform)

Non-split RRM: Located in BS

Profile CSeparate BS and ASN GW

Non-split RRM: Located in BS

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Comparison of ASN Profiles

• Separate BS and ASN GW• Non-split RRM in BS

• Combine BS and ASN GW func.• Non-split RRM in BS

• Separate BS and ASN GW• Split RRM (Radio Resource Management)- RRA (Allocation) in BS- RRC (Controller) in

ASN-GW

Properties

• Extra backhauls for RRM messages

• Able to provide simplified pico-cell• Able to get BS and ASN GW from different vendors

C

• Difficult to customize IP and wireless functions for operators• Expensive for large scale Deployment

• Simple architecture• Suitable for small-scale deployment

B

• Difficult Interoperability between BS and ASN-GW from different vendors• Heavy workload at ASN-GW• Fewer vendors

• Able to provide simplified pico-cell• Able to provide soft handover• Fewer backhauls for RRM messages

A

ConsProsASN

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WiBro and IP Customization

ASN profiles would effects IP customization

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IP Link Models on WiBro

Two IP Link Models for IPv6Shared Link Model

Per-PSS Prefix Model (Point-to-Point Link Model)

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IP Link in IETF (RFC 2461)A communication facility or medium over which nodes can communicate at the link layer.

Examples are Ethernets (simple or bridged), PPP links, X.25, Frame Relay, or ATM networks as well as internet (or higher) layer "tunnels", such as tunnels over IPv4 or IPv6 itself.

Usually bounded by routers that decrement TTL. When an MS moves Inside the same link, it can keep using its IP address.

A prefix can not be assigned to multiple links.

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IP Link Concept in WiMAX

Different PossibilitiesView the bundle of all connections as a single link, or

View each connection as a separate link, or

View the some bundle as one link and others as another link

PSSBS

BS

ASN

ASNGW

PSS

PSS

PSS

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Link Concept ComparisonPSS

RAS

RAS

ACRPSS

PSS

PSS

IEEE 802.16 Link

IPv6 Link

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Shared Prefix Model (I)A Subnet

Consists of only single ACR and multiple RAS and PSS

An ACR can serve one or more BS

PSSRAS

RAS

ACRPSS

PSS

PSS

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Shared Prefix Model (II)Prefix Assign

One or more IPv6 prefixes are assigned to the link and shared by all PSS that are attached to the link

IPv6 prefixes are different from the interface of AR

LinkLink between a PSS and the ACR at the IPv6 link is viewed as a shared link

The lower layer link between the PSS and the RAS is still a point-to-point link

Link Layer Multicast and Broadcast Does not provide link layer multicast and broadcast native capabilities

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Point-to-Point Link (Per-PSS Prefix) Model (I)A Subnet

Each Subnet has a PSS and the ACR

On-link neighbor of a PSS is always the ACR

Each PSS belongs to different subnets (No two PSSs belong to thesame subnet)

PSSRAS

ACR

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Point-to-Point Link (Per-PSS Prefix) Model (II)Prefix Assign

A different 64-bit prefix should be assigned a different link

Note that a prefix is assigned not to a PSS but to the link between a PSS and the ACR

LinkA connection exists (service flow) between a PSS and the AR via an RAS, over which IPv6 packets are transferred

ACR treats the collection of service flow to each PSS as a separate virtual link and manages a virtual interface for each virtual link

Link-scope Multicast Link-scope multicast is also supported, but performed in unicast manner

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Shared Link Model vs. Point-to-Point Link Model

• Would be the same regardless of the link model

• Would be the same regardless of the link model

MS Operation

• Only an MS and an ASN GW belong to the same link

• All MSs belong to the same link

MSs in a Link

• DAD is easy (P2P link between the only MS and

the only ASN GW)

• Special mechanism is needed to run ND

(e.g., Relay DAD)

Duplicated Address Detection (DAD)

• Manages different prefix per MS• Aggregate Prefixes for route injection (Routing table explosion prevention)

Additional Operation at ASN GW

• Unique prefix per a MS (A different RA per MS)

• MSs share the same prefixAddress Management

• Treat the each connection(s) between an MS and an ASN GW as a separate link. (cf. 3GPP)

• Treat the bundle of all connections as a single link.

Connection Management

Point-to-Point Link ModelShared IPv6 Link Model

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Neighbor Discovery (ND)Omniscient ACR

In a WiBro Network, an ACR is aware of all IPv6 addresses currently in use on a link

In the ‘Shared Prefix Model’Every PSS sharing the same prefix are on-link

All packets destined for other PSS in on-link should be transmitted via ACR, and relayed to the on-link destination

ACR should not decrement the hop limit of ND messages, but forward them to other RAS

In the ‘Per-PSS Prefix Model’There is only a PSS and an ACR in a link and the on-link neighbor of a PSS is always the ACR, and vice versa

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DAD procedures on ACRACR must execute proper processing for a successful DAD (Duplicated Address Detection)

WiBro network does not support native multicastWhen a PSS sends NS (Neighbor Solicitation), it is delivered to the default router or ACR, but not to all PSS on the same link

The ACR can take several approaches to implement DADNS ReplicationRelay DADProxy DAD

In ‘Per-PSS Prefix Model’Normally, there is no address conflict in ‘Per-PSS Prefix Model’However, DAD must be performed according to RFC 2462

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DAD procedures on ACR: NS ReplicationACR replicates as many NS sent from PSS as the number of all PSS present

ACR sends replicated NS to each PSS

Not preferableSignificant bandwidth consumption

Processing overheads in ACR

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DAD procedures on ACR: Relay DADACR forwards NS to the PSS (address owner)

On the receipt of an NS for DAD, the ACR searches for an address list maintained within itself

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DAD procedures on ACR: Proxy DADACR takes the responsibility of

Checking the uniqueness of the address in the list

Replying with the corresponding NA instead of the PSS (original address owner)

Efficient in view of Speed

Resource consumption

Cannot be used with SEND (Secure Neighbor Discovery)SEND requires the target address in NA be equal to the source address of the packet

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WiBro MobilityCSN Anchored Mobility: MIP family

ASN Anchored Mobility

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WiBro Related Mobility SolutionsSimple IP

3GPP-like solution

Mobile IP (MIP) or Client Mobile IP (CMIP)MS manages mobility

(Client) Mobile IP(v4) and (Client) Mobile IPv6

Standardized by IETF (Internet Engineering Task Force) MIP4 WG and MIP6 WG

Proxy Mobile IP (PMIP)Mobility Proxy Agent resides in the access network and performs Mobile IP procedures on behalf of MS

PMIPv4 and PMIPv6

WiMAX Forum NWG agrees to support both PMIP and CMIP

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Simple IPL2 extension for Mobility Support

3GPP-like Solution

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Client MIP (CMIP)An IETF compliant MIP solution based on a Mobile IP enabled MS

Termed to differentiate from Proxy MIP in WiMAX

MIP client exists in MS

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Proxy MIP (PMIP)MIP client resides in the access network

performs IP mobility on behalf of MS

Internet

CN

Proxy

MSMS

2

3

44

CoA registration

HoA-CoA binding

CoA

HoA MS’s HA

moving

11

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PMIP ApproachIP Mobility is transparent to the MS.

MS is a simple IP terminal without MIP functionality

AR advertises an RA with MS’s home information so that MS always believes it is on the home link

MIP client (or Mobility Proxy Agent) resides in the access network and performs Mobile IP procedures on behalf of MS

MIP client resides on access router (AR)/ base station (BS), or may be located separatelySecurity information to create Binding Update is learn during authentication phase.

HA does not add special behavior to support PMIPv6HA is unaware that BU is not generated by the actual MS

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PMIPv6 vs. CMIPv6

Security

Processing Delay

Resource Consumption

Mobility Management

DAD latency

In MS

CMIPv6

Security problem between AR and PMIP client when separated

Improved Handover latency

Reduce Air resource consumption

In Network

PMIPv6

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Deploy Mobility ProtocolsIP Mobility Support from MS can be achieved by

MIP with CMIP, or

Simple IP with PMIP

IP Mobility Support from Network depends on MS’s capability of MIPv6

If MS is normal IPv6 without MIPv6 functionality in its profile, AR can serve PMIPv6

Otherwise, AR can serve CMIPv6

PMIP and CMIP can co-exist in the networkNetwork may support CMIP or PMIP or both

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WiMAX Mobility Management• Proxy-MIP: MIP Client resides in ASN-GW

MSSHA

Internet

802.16IP

802.16IP

LNKIP

IPLNK

GREMIP

IPLNK

IPLNK

IPMIP

IPLNK

IP

ASN CSN ASPFA

• Client-MIP: MIP Client resides in MSS

MSSHA

Internet

MIP

802.16IP

802.16IP

LNKIP

IPLNK

GRELNK

IPMIP

IPLNK

IP

ASN CSN ASPFA

IPLNK

IP

IPLNK

GRE

IPLNK

GRE

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WiMAX ASN Profile and Mobility Management

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Example Service: NEMO over WiBroWiBro (Wireless Broadband)

Mobility: over 60km/h

Downstream: about 1Mbps

Upstream: over 128 Kbps

Appropriate for Vehicular Network Mobility

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SummaryIPv6 Mobility over WiBro Solution is dependant on

CS type

IP Link Model

Service scenario, Cost, Efficiency will be parameters for the decision

IP Mobility Services and IP Mobility-related Services would be prosperous with WiBro, since WiBro provides

High data rate

Mobility

Wide Coverage

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Issues L2 Mobility Support vs. L3 Mobility Support

Global Mobility Support vs. Local Mobility Support

Host-Based Mobility Support vs. Network-Based Mobility Support

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WiBro Perspectives

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What is Key Technologies for Future Network ?

Key Requirements for Future Internet

What Users want ? That is where we start !QoSMobilitySecurityetc.

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New Environment and New Demand for Future Mobile Networks

Complexity

(Heterogeneous Wireless Networks)

Personalization

(Ubiquitous Networks)

Instant,

Easy Management

for

Individuals

ArchitectureOperation

Commercialization

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Mobile Routing Architecture

e.g., MANET for NEMO (MANEMO)

Integration of Infrastructured and Infrastructure-less Mobile Routing

e.g., Mobile Ad hoc Networks (MANET)

Infrastructure-less Mobile Routing

e.g., Host Mobility (MIP), Network Mobility (NEMO)

Infrastructured Mobile Routing

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Autonomic Management with Multihoming

e.g., Find the optimized path to the Internet

Self-Optimizing

e.g., Configures new addresses when it moves

Self-Configuring

e.g., Detects whether it is attached to or detached from the Internet, then Recovers failed association

Self-Healing

e.g., Authenticate multiple components, e.g., Mobile routers

Self-Protecting

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Emerging Challenges Identification and Location

Routing and Forwarding

Authentication, Authorization, and Accounting

etc.

Will effect Future Mobile Network Technology

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Concluding Remarks: Importance of IP Mobility

Various wireless technologies for mobile networking demands for common mobility management protocol over layer 3

IP mobility enables all-IP applications

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Innovative Thinking for Future MobilityFor example,

Old: Get Wire Connected

New: Remove Wires

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Innovative ApproachesSustaining Innovation vs. Disruptive Innovation

Convergent Thinking vs. Divergent Thinking

Simple is beautifulWhat is simple ? How to be simple ?

“A designer knows he has achieved perfection not when there is nothing left to add, but when there is nothing left to take away.“- Antoine de Saint-Exupery

Know our strength e.g., Autonomic Computing (IBM)e.g., Simplicity (MIT Media Lab.)e.g., Digilog (Korea)

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How to start ?“Instead of trying to save the world,

start with a small, concrete goal of

solving a specific problem and

explore tradeoffs.”

- Douglas Comer

Internet Innovation Workshop, June 2007

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ReferencesIETF Homepage (http://www.ietf.org)

GENI (Global Environment for Network Innovations) Homepage, http://geni.net/

C. Ng, T. Ernst, E. Paik, M. Bagnulo, “Analysis of Multihoming in Network Mobility Support,” IETF I-D, Feb. 2007.

Nakjung Choi, Jiho Ryu, Eunkyoung Paik, Taekyoung Kwon and Yanghee Choi, "A Transparent Failover Mechanism for a Mobile Network with Multiple Mobile Routers," IEEE Communications Letters, 2007.

한연희, 백은경, “와이브로에서의 IPv6 기술,” TTA Journal, No. 109, pp.77-81, Jan. 2007.

백은경, 이상홍, 장병수, “와이브로네트워크를위한 IPv6 이동성과다중접속기술표준화,” TTA 제 1회정보통신표준화우수논문집, pp. 7-30, Dec. 2005.

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Contact

PAIK, Eun [email protected]