Fast-handoff Mechanisms for Wireless Internet Presenter - Ashutosh Dutta 04/12/2005 IRT Group...

Fast-handoff Mechanisms for Wireless Internet

Presenter - Ashutosh Dutta04/12/2005

IRT Group [email protected]

IRT Talkl - 2

Outline

Motivation Handoff Delay during Wireless Internet Roaming Related Work Multi-Interface/Inter-Technology Handoff Experimental Results

– MIP-based, SIP-based (binding)

Proposed Ways to Optimize the handoff– Multi-interface mobility management– Proactive Handover– SIP-based fast-handoff– Proxy-based handoff for multicast stream

IRT Talkl - 3

Motivation

It is desirable to limit the jitter, delay and packet loss for VoIP and Streaming traffic

150 ms end-to-end delay for interactive traffic such as VoIP, 3% packet loss is allowed

Delay due to handoff takes place at several layers– Layer 2 (handoff between AP), Layer 3 (IP address

acquisition, configuration) and Media Redirection Rapid handoff will contribute to overall delay and

packet loss Thus it is essential to reduce the handoff delay

introduced at different layers We propose several mechanisms to reduce the

handoff-delay and packet loss

IRT Talkl - 4

Mobile Wireless Internet: A Scenario

802.11a/b/g

Bluetooth

IPv6Network

UMTS/CDMA Network

InternetDomain1

Domain2

UMTS/CDMA

PSTN gateway

Hotspot

CHRoaming User Ad Hoc

Network

PAN

LAN

WAN

WAN

LAN

PSTN

802.11 a/b/g

IRT Talkl - 5

Internet

Visited Domain

AP

AP

ERC

AP

BS

BS

A

C

BD

Home Registrar

Visited Registrar

Corresponding Host

SIP enabled

128.59.10.6

IPch

207.3.232.10

207.3.232.10207.3.240.10

SLA/SA

128.59.11.6

N2

N1N1

N2

N1- Network 1 (802.11)N2- Network 2 ( CDMA/GPRS)

DHCP/PPP

ERC ERC

ERC - Edge Router and Controller

MN

SIP Server

QoS

AAA AAA

QoS

SIP Server

PublicSIP Server

Public AAA

VR HR

Home Domain

DHCP/PPPDNS

DNSPANA PANA

Internet

Visited Domain

AP

AP

ERC

AP

BS

BS

A

C

BD

Home Registrar

Visited Registrar

Corresponding Host

SIP enabled

128.59.10.6

IPch

207.3.232.10

207.3.232.10207.3.240.10

SLA/SA

128.59.11.6

N2

N1N1

N2

N1- Network 1 (802.11)N2- Network 2 ( CDMA/GPRS)

DHCP/PPP

ERC ERC

ERC - Edge Router and Controller

MN

SIP Server

QoS

AAA AAA

QoS

SIP Server

PublicSIP Server

Public AAA

VR HR

Home Domain

DHCP/PPPDNS

DNSPANA PANA

SIP-centric Wireless Internet Roaming

IRT Talkl - 6

Trajectory of a Packet

Source

PCM sample

CompressedpacketT1

T2

T3

T4

T5

T6

T7VoIPPacket (Application)

Receiver

Total E-E delay = ∑T i

Transmission+ Handoff

T1 = Encoding DelayT2 = Packetization DelayT3 = Transmission DelayT4 = Handoff DelayT5 = Jitter buffer delayT6 = De-Packetization delayT7 = Decoding Delay

P1

P1

PN

T5 = 0P1

T6

T7

P1

P1

P1PN

PN

PN

T5

Total Packet Loss = PN – P1

Time Nohandoff

Handoff

LostPackets

VoIPPacket

IRT Talkl - 7

Handoff Latency

AP1 AP2NextAccessRouter

Router Advertisement

DHCP serverPPP

DHCP/PPP

HA/SIP Server

Binding Update

CN

Media

New Media

Binds to AP1

Layer 2 Association

Dual mode MN

Stateless Auto-configuration

AAA

DAD/ARP

AAAServer

Layer 2 Security

VPN

VPNGW

1- L2 Hand-over Latency Delay

2 – Delay due toIP Address Acquisition and Configuration, authentication, authorization

3 – Binding update and Media Redirection delay

1

2

3

1

2

3

IGMP/RTCP

IRT Talkl - 8

Sample Delays (L3, L2)

Under

study

100 ms4-5

s

1 – 2

s

150 ms4-5

s

Time

2

Proactive

IP

StaticAuto

IP

FA

COA

DHCP (v6)DHCP

ARP w/o

Method

(Linux)

Under

study

100 ms4-5

s

1 – 2

s

150 ms4-5

s

Time

2

Proactive

IP

StaticAuto

IP

FA

COA

DHCP (v6)DHCP

ARP w/o

Method

(Linux)

300- 400ms

DRCP

160ms

500ms

PPP

7-8s

H/W - OS L2 Handoff

AiroNet +Linux 200 – 300 ms

Orinoco+Linux 100 – 160 ms

DLink +Linux 400 – 600 ms

Centrino + Linux (Passive)

300 ms

Orinoco +Windows 250 ms

Hostap (Managed) 14 ms

L3 Delay

L2 Delay

SA SF

IRT Talkl - 9

Mobility Optimization - Related Work Cellular IP, HAWAII - Micro Mobility

MIP-Regional Registration, Mobile-IP low latency, IDMP

HMIPv6, FMIPv6 (IPv6)

Yokota et al - Link Layer Assisted handoff

Shin et al, Velayos et al - Layer 2 delay reduction

Gwon et al, - Tunneling between FAs, Enhanced Forwarding PAR

DHCP Rapid-Commit, Optimized DAD - Faster IP address acquisition

DFA, MOM (Multicast)

IRT Talkl - 10

Possible Handover Scenario

Handover between 802.11 and 802.3 networks Handover between 802.3 and 802.16 networks Handover between 802.11 and 802.16 networks Handover between 802.11 and 802.11 networks,

across ESSs. Handover between 802.3 and Cellular networks Handover between 802.11 and Cellular networks Handover between 802.16 and Cellular networks

IRT Talkl - 11

Single Radio Interface Roaming Scenario

Provider B

Provider A

IEEE 802.11 LAN

Subnet A1(or ESS A1) Subnet A2(or ESS A2) Subnet B1 (or ESS B1)

IEEE 802.11LAN IEEE 802.11LAN

Intra-domainInter-subnet MIH

Inter-domainInter-subnet MIH

IRT Talkl - 12

Handoff with Single Interface (802.11-802.11) Example

MN AP1 AP2 R2 DHCP

Network 1 (802.11) Network 2 (802.11)

Assign IP0 to PhysicalI/F

CN

Data

-

SIP Re-invite with IP1

Data

R1

Network 3

-

PANA/AAAAssign IP1 to PhysicalI/F

DHCP

MNL2 handover

Packet loss period

IRT Talkl - 13

Multiple Radio Interface Roaming Scenario

IEEE 802.11 LAN IEEE 802.11LAN

Cellular Network (CDMA/GPRS)

WLAN: ActivatedCellular: deactivated

The mobile detects Cellular starts the connection, WLAN: deactivated

MobileDetects 802.11 may disconnectcellular

IRT Talkl - 14

Effect of handoff delay on audio (Non-Optimized)

Figure 3. Multiple Interface Case (802.11b – CDMA1XRTT) – MIP as mobility

802.11 802.11CDMAHandoff19 s

Figure 1. Single Interface Case (802.11b – 802.11b) – SIP as mobility

802.11 802.11Handoff

4 s

Handoff17 s

802.11 CDMA 802.11

Figure 3. Multiple Interface Case (802.11b – CDMA1XRTT) – SIP as mobility

IRT Talkl - 15

SIP-based subnet and domain Mobility handoff (Experimental Results)

CH MH

59.521 - 10.1.4.162

00.478RTP2

RTP1

00.652

00.701

RTP2 00.938

RTP1

00.949

00.960

01.031

01.151

(De-REG+REG) (01.049, 01.052)

01.37

00.759 - 10.1.1.130

DRCP DISCOVER

DRCP OFFER

DRCP ACK

PANA

Re-INVITE

OK

ACK

Pr

Pr = 220 ms

RTP1

01.52 – 10.1.1.130

Pr

TimeSec

Handoff timing with more granularity

Operation DRCP PANA SIP Media

RTP

Subnet

Handoff

79 ms 2 ms 228 ms

1490 ms

Domain

Handoff

81 ms 45 ms 289

ms

1656

ms

Fig 1. Handoff Factors for SIP-based mobility

Table 1. subnet/domain handoff Experimental values

2 3 3

Handoff

(L2+DRCP+PANA)

CHMH

Old IP address IP1

New IP

address IP2

Re-Invite

X

RTP to IP1

RTP to IP2

OK

ACK

RTP to IP1

Voice20 msec

time interval

X

Pr

Pr

Pr

Handoff

(L2+DRCP+PANA)

CHMH

Old IP address IP1

New IP

address IP2

Re-Invite

X

RTP to IP1

RTP to IP2

OK

ACK

RTP to IP1

Voice20 msec

time interval

X

Pr

Pr

Pr

IRT Talkl - 16

Temp. key for alice@domain1

Inter-domain Secured Mobility

CH

Domain1 (Home network))

DIAMETER ClientPANA Agent w/FirewallDRCPIPSec

DIAMETER Server (AAA Home)

Domain2 (Foreign network)

Mobile Station

PANA ClientNAI=alice@domain1

Pre-shared key for alice@domain1

DIAMETER Server(AAA Foreign)

DIAMETER ClientPANA Agent w/Firewall DRCP IPSec

SIP Proxy

SIP Proxy

APAP

INV

ITE

2302

Moved

3

RTP Key

4 INVITE

Temp. key for alice@domain2

MNRTP Key

MN 5 Re-INVITE

1Register

MN

IRT Talkl - 17

CH MH

RTP1

RTP1

23.806 – 10.1.4.162

207.3.232.156

24.046RTP2

24.086

24.156

24.176

DRCP OFFER

DRCP ACK

24.196 – 10.1.1.130

PANA-AAA

24.216

24.246

IKE

28.25629.356

Mobile IP

29.376

31.186 – 10.1.1.130

RTP1 (IPIP)RTP1

TIME(Sec)

CH MH

RTP1

RTP1

23.806 – 10.1.4.162

207.3.232.156

24.046RTP2

24.086

24.156

24.176

DRCP OFFER

DRCP ACK

24.196 – 10.1.1.130

PANA-AAA

24.216

24.246

IKE

28.25629.356

Mobile IP

29.376

31.186 – 10.1.1.130

RTP1 (IPIP)RTP1

TIME(Sec)

Fig 3b. MIP-based secured Inter-domain mobility handoff timing

Effect of multilayer security on handoff - SIP-MIP

SIP-DRCP-PANA-AAA-IPSEC MIP-DRCP-PANA-AAA-IPSEC

CH MH207.3.232.156

RTP1

RTP1

51.756 – 10.1.4.162 (domain1)

RTP2 52.06652.146

DRCP OFFER

52.176ACK 52.226

PANA-AAA

52.266 – 10.1.1.130 (domain2)

52.27652.346

ISAKMP

52.666

52.796OK

ACK

PrPr

Pr RTP1

53.066 – 10.1.1.130

TimeSec

52.906

CH MH207.3.232.156

RTP1

RTP1

51.756 – 10.1.4.162 (domain1)

RTP2 52.06652.146

DRCP OFFER

52.176ACK 52.226

PANA-AAA

52.266 – 10.1.1.130 (domain2)

52.27652.346

ISAKMP

52.666

52.796OK

ACK

PrPr

Pr RTP1

53.066 – 10.1.1.130

TimeSec

52.906

Fig 3a. MIP-based secured Inter-domain mobility handoff timing

Media Interruption – 1.31 sec Media Interruption – ~ 7 s

IRT Talkl - 18

Need for fast-handoff (An example)

MN

InternetVisited Domain

MN

MN

Public SIP Proxy

Public SIP Proxy

Public SIP Proxy

IP0

IP1

IP2

Visited Proxy/OutboundSIP server

Home SIP Proxy

Transient Data

Re-Invite

OK ACK

CN HomeDomain

SubnetS0

SubnetS1

SubnetS2

RTPMedia afterRe-Invite

Register1

Translator

Translator

Control signal

New data

Transient data

Move Move

- Round trip time from London to Sydneyis 540 ms, 28 hops-London – Berkley Is 136 ms, 22 hops

IRT Talkl - 19

Fast-handoff mechanismsKey Design Principles:

– Limit the signaling due to Intra-domain Mobility– Capture the transient packets in-flight and redirects to the mobile– Obtain IP address proactively and send binding update in the previous

network– Make-before-break in multi-interface case– Communicates proactively with CH before the handoff takes place by doing

pre-authentication– Have a proxy joins the multicast stream on behalf of the impending client

Methods currently experimented– SIP Registrar and Mobility Proxy-based – Proactive secured handoff (MPA)– Proxy-based handoff for Multicast Streaming

Other SIP-based fast-handoff methods for comparison– Outbound SIP proxy server and mobility proxy– B2BUA and midcom– Multicast Agent

IRT Talkl - 20

SIP fast-handoff mechanism using mobility proxy

MH CHVisited SIP

Registrar

Media

MobilityProxySubnet 1

IP1

IP2(New Address)

Re-INVITE (2)

REGISTER 2’

Forward traffic(IP1:p1 ---> IP2:p1)

New traffic

IP3(New Address)

Re-INVITERe-REGISTER

Forward traffic(IP2:p1 ---> IP3:p1)

Transient Traffic during the move

(1)

SIP-CGI (3)

Transient Traffic during the move

SIP-CGI

First move

Second moveIP2

DelayBox

OutboundServer

MobilityProxySubnet 2

MobilityProxy Subnet 3

IRT Talkl - 21

Heterogeneous Mobility (Host-based)

MIMM provides innovative techniques and algorithms to support• Fast handoff among heterogeneous radio systems• Fast and resource-efficient path quality comparison to allow terminal to pick the interface that best fits is applications’ QoS needs at the lowest power consumption

Laptop or PDA

BTAP

802.11AP

Corresponding Host

Router/MIP FA

802.11AP

MIP HA

TestbedCore Network

Visited Network A Visited Network B

Home Network

EtherBridge

Data,Video Stream,

Voice

CellularNetwork

(cdma2000, GPRS)

Internet

R R

Router/MIP FA

MIMM MIMM MIMM

Visited Network C

IRT Talkl - 22

Multi-Interface Mobility Management - Results

MN CH

MIMM decide switching interface

INVITE with new IP address

200 OK

ACK

RTP/UDP session destined to the new Interface

MN HA

MIMM decide switching interface

RRQ with life time = 0 for old addr

RRQ with life time > 0 for new addr

RRP with life time > 0 for new addr

RTP/UDP session forwarded to the new Interface

RRP with life time = 0 for old addr

CH RTP/UDP session destined to Home address

HA stops forwarding packet in

this duration

(a) handoff signaling sequence in SIP mobility

(b) handoff signaling sequence in Mobile IP

Time (10 seconds/grid)

Pac

ket

Se

qu

en

ce N

um

be

r

(500

pac

kets

/gri

d)

3G Cellular

802.11b

Time (10 seconds/grid)

Pac

ket

Se

qu

en

ce N

um

be

r

(500

pac

kets

/gri

d)

3G Cellular

802.11b

Movement type

Cellular- 802.11b

802.11b –

Cellular

Handoff

Trials

#1 #2 #1 #2

INVITE -> OK 0.12 s 0.12 s 1.32 s 6.64 s

INVITE ->

1st Packet

0.39 s 0.41 s 2.54 s 7.18 s

Re-transmission None None Yes Yes

Figure 1: SIP-based Mobility with MIMM

Figure 2: Timing for SIP-based Mobility

IRT Talkl - 23

SIP Mobility (without make-before-break) 802.11-CDMA

MN CN

RTP 60402

eth0 22.772

eth0 22.812

ppp0 38.453Re-INVITE

Re-INVITE (Re-trans)ppp0 38.965

ppp0 39.759OK

ppp0 39.878 ACK

WLAN is gonePPP0 is coming up

RTP 60403

RTP 59962

RTP 59963

ppp0 40.769

ppp0 40.869

ppp0 40.969 RTP 60404

RTP 60405 ppp0 41.719

ppp0 41.729 RTP 60406

RTP 59961eth0 22.733

JitterIn cellularnetwork

CN – 165.254.55.2MN – WLAN – eth0 – 10.1.10.2 CDMA – PPP0 – 166.157.12.179

Delay18 s

PPPSetup~16 s

Packets sent at 40 ms interval

Packets sent at 40 ms interval

IRT Talkl - 24

SIP Mobility (MIMM) – Make-before-break (802.11 – CDMA)

MN: WLAN - Eth0 – 10.1.10.2 CDMA - PPP0 – 166.157.116.186CN – 165.254.55.2

•Jitter observed in Cellular Network-Several Re-INVITE retransmission in CDMA network-Packets are received in eth0 duringSIP Re-INVITE sequence- No packets are lost during the handoff

MN CN

(ppp0)

RTP (28790)16.202

16.240

16.242RTP (28791)

(eth0)

(ppp0)

(eth0)

Re_INVITE (IP1)

Re-INVITE (Re-trans) –IP116.750(ppp0)

RTP (28792)16.285(eth0)

16.322

16.362

RTP (28793)

RTP (28794)

Re_invite (Re-trans)- IP117.761

RTP

RTP

(eth0)

(eth0)OK

19.639(ppp0)RTP(eth0)

19.758ACK

(ppp0)RTP

RTP(eth0)

(eth0) 28888

RTP 2888920.549(ppp0)

20.122

20.669(ppp0)RTP 28890

Handoffdelay

20.769(ppp0)

20.869

(eth0)

(eth0)

IRT Talkl - 25

Mobility with VPN

DMZ

Internal (protected) External (unprotected)

CN

Internal Home

Network

VPN tunnel x-MIP tunnel

VPN GW x-HA

Based on its current location, MN dynamically establishes/changes/terminates tunnels

without changing current standards of IPsec VPN or Mobile IP. Triple encapsulation tunnel is constructed by:• i-HA (Internal Home Agent): Forwards IP packets to MN’s current internal location• VPN GW: Protects (encrypts and authenticates) IP packets transmitted in external

networks • x-HA (External Home Agent): Forwards IP packets to MN’s current external location

MN

i-MIP tunnel

Internal Visited

Network

i-HA

MNMN MN

ExternalNetwork 1

ExternalNetwork N

IRT Talkl - 26

Demonstration Scenario

DMZ


CN

VPN GW

x-HA

MNMN

ExternalNetwork(Cellular)Internal Home Network

(WLAN)

i-HA

MN

Step 1: MN (at its home network over WLAN) and CN start an application session, then MN starts moving

IRT Talkl - 27


DMZ


CN


VPN GW

x-HA

MNMN


(WLAN)

i-HA

MN

Step 2: MN starts preparing alternate path by establishing x-MIP and VPNtunnel over the cellular link, while keeping communication via the home network over WLAN

IRT Talkl - 28


DMZ


CN


VPN GW

x-HA

MN

i-MIP tunnel

MN


(WLAN)

i-HA

MN

Step 3: MN stops using its home WLAN, starts using cellular and establishes i-MIP tunnel, then continues communication with CN

IRT Talkl - 29

Internet

X-HA

205.132.6.64/27

65

.66 - .94

DMZ Network

ExternalCellular

66

67

HoA = 70-75VPN

GW100(99)

Internal Visited

TIA = 111-120

10.1.10.0/24

98

10.1.20.0/24

3CH

i-HA

LinuxR

1HoA = 210-215

Internal Home(SSID=ITSUMO home)(demo.tari.toshiba.com)

AP

SIPMonitor

2

4DNS

ExternalHotspot

Earth Link DSL

MN

MN

VerizonCDMA 1XRTT

DHCP

Enterprise Firewall

Mobile-IP with VPN Experimental Testbed

IRT Talkl - 30

Step-by-step protocol flow

CN MN i-HA VPN-GW x-HA

……

CDMAPPP

Connectionsetup

RTP

i-MIP Request

i-MIP Reply

x-MIP Request

x-MIP Reply

ISAKMP + x-MIP

ISAKMP

ISAKMP

ISAKMP + x-MIP

……

802.11

SNR = S1

Data on


……

CDMAPPP

Connectionsetup

RTP

i-MIP Request

i-MIP Reply

x-MIP Request

x-MIP Reply

ISAKMP + x-MIP

ISAKMP

ISAKMP

ISAKMP + x-MIP

……

802.11

SNR = S1

Data on


RTP ESP + x-MIP

ESP

ESP

ESP + x-MIP

i-MIP Request

i-MIP Reply

UDP + i-MIP

RTP

ESP

ESP + x-MIP

……

SNR=S2

DataOver

CDMA(tripple

Tunneled)

MakeBeforeBreak


RTP ESP + x-MIP

ESP

ESP

ESP + x-MIP

i-MIP Request

i-MIP Reply

UDP + i-MIP

RTP

ESP

ESP + x-MIP

……

SNR=S2

DataOver

CDMA(tripple

Tunneled)

MakeBeforeBreak

PPP setup over CDMA at SNR (S1) Make-before-break scenario at SNR = S2

Mobile coming back home


1xrttDisconnection

RTP

i-MIP Request

i-MIP Reply

ISAKMP + x-MIP

ISAKMP

ISAKMP

ISAKMP + x-MIP

……

MNBack home DataOn

802.11

VPNTunnel

Teardown

Out-of-order Transient packets


1xrttDisconnection

RTP

i-MIP Request

i-MIP Reply

ISAKMP + x-MIP

ISAKMP

ISAKMP

ISAKMP + x-MIP

……

MNBack home DataOn

802.11

VPNTunnel

Teardown

Out-of-order Transient packets

IRT Talkl - 31

Non-Make-before-break

3150032000325003300033500340003450035000

0 50 100 150 200 250 300

Time in Seconds

RT

P S

equ

ence

RTP Sequence

802.11(enterprise)

Cellular

802.11(enterprise)

Packet LossDue to Non-make-before-break

Non-make-before-break

Non-make-before-break situation

IRT Talkl - 32

SUM (make-before-break)

802.11-Cellular Secured Handoff

18001900

200021002200

23002400

25002600

0 20 40 60 80 100 120 140 160 180

Time in Seconds

RTP

Pac

ket

Sequ

ence

RTP sequence duringhandoff

Out-of-order-packet

802.11(enterprise)

Cellular

802.11(enterprise)

IRT Talkl - 33

Home-cellular-Hotspot

Home-Cellular-Hotspot handoff

500

1500

2500

3500

4500

5500

0 100 200 300 400

Time in Seconds

RT

P S

eq

uen

ce

RTP Sequence

Home802.11

CellularExternal

Hotspot802.11

IRT Talkl - 34

Operation Timing

PPP setup 10 sec

X-MIP 300 ms

VPN Tunnel

setup

6 Sec

I-MIP 400 ms

I-MIP (Home) 200 ms

IPSEC 60 ms

DHCP 3 Sec

TransmissionDelay 5 ms 802.11

2.5 s cellular

Packet Transmission Delay for Voice Traffic

0.00000010

0.00000100

0.00001000

0.00010000

0.00100000

0.01000000

0.10000000

1.00000000

36

46

0

37

800

39

14

0

40

48

0

41

82

0

43

25

2

455

86

49

31

7

52

62

4

56

93

3

60

94

0

62

280

63

62

0

Packet Numbers

Tra

ns

mis

sio

n D

ela

y i

n (

Lo

g S

ca

le)

Transmission Delay

802.11

Cellular

802.11

Packet Transmission Delay for Voice Traffic

0.00000010

0.00000100

0.00001000

0.00010000

0.00100000

0.01000000

0.10000000

1.00000000

36

46

0

37

800

39

14

0

40

48

0

41

82

0

43

25

2

455

86

49

31

7

52

62

4

56

93

3

60

94

0

62

280

63

62

0

Packet Numbers

Tra

ns

mis

sio

n D

ela

y i

n (

Lo

g S

ca

le)

Transmission Delay

802.11

Cellular

802.11

Inter-Packet Delay Variation betw een CH and MH (Voice)

0.0010

0.0100

0.1000

1.0000

10.0000

36

46

0

37

48

4

38

50

8

39

53

2

40

55

6

41

58

0

42

60

4

44

01

2

46

01

9

48

86

7

51

67

1

54

17

2

58

27

9

60

85

2

61

87

6

62

90

0

Packet Numbers

Inte

r-P

ac

ke

t D

ela

y d

iffe

ren

ce

(l

og

sc

ale

)

Delay Variation

802.11 802.11

Inter-Packet Delay Variation betw een CH and MH (Voice)

0.0010

0.0100

0.1000

1.0000

10.0000

36

46

0

37

48

4

38

50

8

39

53

2

40

55

6

41

58

0

42

60

4

44

01

2

46

01

9

48

86

7

51

67

1

54

17

2

58

27

9

60

85

2

61

87

6

62

90

0

Packet Numbers

Inte

r-P

ac

ke

t D

ela

y d

iffe

ren

ce

(l

og

sc

ale

)

Delay Variation

802.11 802.11

(a) Packet Transmission Delay

(c) Inter-packet departure and arrival delay variation for CBR (Voice)

Mobile IP with VPN

Handoff and delay with multiple Interfaces (MIP-VPN)

Inter-Packet Delay v ariation between CH and MH (Video)

0.001000

0.010000

0.100000

1.000000

10.000000

23

41

8

23

44

9

23

48

0

23

51

1

23

54

2

23

57

3

23

60

4

23

63

5

23

66

6

23

69

7

23

73

2

23

76

3

23

79

4

23

82

5

23

85

6

23

88

7

23

91

8

23

94

9

23

98

0

24

01

1

24

04

2

24

07

3

24

10

4

24

13

5

24

16

6

24

19

7

Packet Number

Inte

r-P

ac

ke

t D

ela

y V

ari

ati

on

(L

og

Sc

ale

)

Inter D iff

Cellular 802.11b802.11b

Inter-Packet Delay v ariation between CH and MH (Video)

0.001000

0.010000

0.100000

1.000000

10.000000

23

41

8

23

44

9

23

48

0

23

51

1

23

54

2

23

57

3

23

60

4

23

63

5

23

66

6

23

69

7

23

73

2

23

76

3

23

79

4

23

82

5

23

85

6

23

88

7

23

91

8

23

94

9

23

98

0

24

01

1

24

04

2

24

07

3

24

10

4

24

13

5

24

16

6

24

19

7

Packet Number

Inte

r-P

ac

ke

t D

ela

y V

ari

ati

on

(L

og

Sc

ale

)

Inter D iff

Cellular 802.11b802.11b

(c) Inter-packet departure and arrival delay variation for VBR (Voice)

IRT Talkl - 35

MOBIKE-flow (802.11-Cellular-802.11)

MNVPN GW

Visited Network 1(802.11)

Visited Network 2(Cellular)

CN

Tunnel (RTP)

45.232 (Last packet on 802.11)

MOBIKE

MOBIKE45.522

44.948 (PPP is up)

46.312 (First packet on Cellular)

46.432

46.469


51.894 (802,11 is primary interface)

51.915

MOBIKE

MOBIKE

28:52.019

28:44.091

PacketLoss(Break-before-make)

Make-before-breakNo packet loss

RTP

VPN traffic in 802.11

VPN traffic in cellular

Mobike in cellular

Mobike in 802.11

MN moves from 802.11 (hotspot) to Cellular to 802.11 (hotspot)

IP0 is primary address



IP0 – address of 802.11 interfaceIP1 – address of cellular interface

IRT Talkl - 36

MOBIKE-flow (Cellular-802.11-Cellular)

MN moves from Cellular to 802.11 (hotspot) to Cellular

No packet lossOut-of-order-packet(make-before-break)

MNVPN GW



CN

Tunnel (RTP)

MOBIKE

MOBIKE

13.377

13.342 ( 802.11 is up)

13.554 (First packet on 802.11)

47.881

51.519

MOBIKE

51.977

PacketLoss(No-Break-before-make)

RTP


13.667 (Last packet on cellular)

MOBIKE

43.103 (Last packet on 802.11)

VPN traffic in 802.11

VPN traffic in cellular

Mobike in cellular

Mobike in 802.11




IP0 – address of 802.11 interfaceIP1 – address of cellular interface

IRT Talkl - 37

MPA-assisted Seamless Handoff (a scenario)

AR

AP1

Mobile

AP2

AP3

AP0

AA CA

MN-CA keyAA CA

MN-CA key

AA CA

MN-CA key

CN

AR

AR

Network 1

Network 2

Network 3

CurrentNetwork TN

Information Service (e.g.,802.21) mechanism can help locate the neighboring network elements in the candidate target networks (CTN)

CTNCTN

CTN – Candidate Target NetworksTN – Target Network

IRT Talkl - 38

Functional Components of MPA

1) Pre-authentication/authorization– Used for establishing a security association (SA) between

the mobile and a network to which the mobile may move– L2 pre-authentication can also be enabled based on the

established SA

2) Pre-configuration– Used for establishing contexts specific to the network to

which the mobile may move (e.g., nCoA)– The SA created in (1) are used to perform secured

configuration procedure

3) Secured Proactive Handover – Used for sending/receiving IP packets based on the pre-

authorized contexts by using the contexts of the current network

NetworkL2info

L3info802.11

GPRS

GSM

802.16

W-CDMA

cdma2000

Cipher

standard

channel

802.11-SSID

BSSID

phy

Data_rates

Nsp_code

Nsp_name

Nsp_tariff

WEP

TKIP

AES-CCMP

AKM

Psk

802.1x

KMP

11i4w

L2QoS

802.11e Cost

RoamingList

L2Mobility

802.21

802.11r

L2PreAuth802.11u

IPv4

IPv6

KMP

Router_addr

DHCP_addr

Domain_name

subnet

Sip_server

IKEv1 IKEv2

Auth

PANA

PAA_addr

EP_addr

Ciphering

IPsec

ISP_code

ISP_name

ISP_tariff

L3Mobility

MIPv4

HA_addr

FA_addr

UAM

CT

CARD

L3Preauth

L3QoS

VPN_server

Location

Latitude

longitude Civic-addr

AP-ID

IRT Talkl - 40

Expected Result

TimeConventionalMethod

Detectnew AP in different subnet L2 handoff

starts

L3 handoffstarts

MPA

Detectnew AP

Pre-auth/Pre-authzCompletes(L2 SAs can be ,completed here.)

L2 handoffstarts

L3 handoffcompletes

L2 handoffcompletes

L3 handoffstarts

L2 handoffcompletes

Critical period (communication interruption can occur)

L3auth/authzstarts

L3 auth/authzcompletes

Time

Pre-auth/Pre-authzstarts

L2 auth/authz,starts

L3 handoffcompletes

IRT Talkl - 41

Pre-Authentication

Subnet X Subnet Y

CN: Correspondent NodeMN: Mobile NodeAA: Authentication AgentCA: Configuration AgentAR: Access Router

AA CA AR

MN

pre-authentication

CNDATA[CN<->A(X)]

SIP mobility is just an example mobility protocol. MPA works for any mobility management protocol

IRT Talkl - 42

Pre-authorization

CN

AA CA AR

MN

IP address: A(X)Current subnet: XStatus: Pre-authentication doneAction: pre-authorization

DATA[CN<->A(X)]

MN-CA key

pre-authorization

Subnet X Subnet Y


IRT Talkl - 43

Proactive Handover: Initial Phase


MN

IP address: A(X), A(Y)Current subnet: XStatus: Pre-authorization doneAction: PH Initiation

AA CA AR

MN-AR key

Secure Proactive Handover tunnel

establishmentprocedure

CNDATA[CN<->A(X)]

Subnet X Subnet Y

IRT Talkl - 44

Proactive Handover: Tunneling Phase


AA CA

MN

IP address: A(X), A(Y)Current subnet: XStatus: PH tunnel establishedAction: SIP Re-Invite

MN-AR key

SIP Re-Invite over proactive hanodvertunnel [AR<->A(X)]

CNDATA[CN<->A(X)]

AR

Subnet X Subnet Y

Re-Invite[CN<->A(Y)]

IRT Talkl - 45

Proactive Handover: Completion Phase


AA CA

IP address: A(X), A(Y)Current subnet: XStatus: SIP Re-Invite doneAction: PH Completion

DATA [CN<->A(Y)] over proactive hanovertunnel [AR<->A(X)]

AR

Proactive handoverstop procedure

MN

L2 handoff procedure

Subnet X Subnet Y

CN

IRT Talkl - 46

MPA Communication Flow

MN oPoA nPoA AA CA AR

1. Found CTN

Candidate Target Network

Pre-authentication[Authentication Protocol]

MN-CA Key

MN-AR Key2. High probability to switch to the CTN

Pre-configuration [Configuration Protocol to get nCoA]

Pre-configuration [tunnel management protocol to establish PHT

3. Determined to switch toThe CTN Secure Proactive Update Phase

Binding Update + data Transmission over PHT using nCoA

4. BU completion andReady to switch

Secure proactive handover pre-switching phase [tunnel management protocol to delete PHT]

CN

5. Switching Post Switching Phase: Reassignment of nCoA to its physical Interface

Existing session using oCoA

New Data using nCoA

IRT Talkl - 47

MPA Optimization Issues

Network Discovery– Discover the neighboring network elements (e.g., Routers, APs, Authentication Agents)– 802.21 (Information Service), 802.11u, WIEN SG, CARD, DNS/SLP

Proactive IP Address Acquisition

Proactive Duplicate IP address Detection

Proactive Address Resolution

Proactive Tunnel Management

Proactive Mobility Binding Update

Bootstrap Link-layer Security in CTN using L3 Pre-authentication

IRT Talkl - 48

Protocol Set for the MPA demonstration

Pre-authentication protocol PANA

Pre-configuration protocol PANA, DHCP Relay

Proactive handover tunneling protocol IP-in-IP

Proactive handover tunnel management protocol

PANA

Mobility management protocol SIP Mobility

Link-layer security None

IRT Talkl - 49

Experimental Network in the Lab.

IP0: 10.10.40.20 IP1: 10.10.10.223

AP1, AP2: Access PointR1, R2: Access RouterMN: Mobile NodeCN: Correspondent NodeIP0, IP1: IP address of MN

R2R1

10.10.20.52/2410.10.20.52/24

10.10.40.52/24

10.10.10/24

10.10.10.51

eth0

eth0

eth2

SIP with VIC/RATApplication

DHCPServer

Relay/Client Proxy

PANAAgent

10.10.30.25

Network 1 Network 2

IP2

AP1(Channel 6)

AP2(Channel 9)ITSUMO network

DHCPServer

Move

AA

CA

AR

CNMN MN

10.10.30/24

Network 3

AR

IRT Talkl - 50

Protocol flow for MPA

MN AP1 AP2 R2 DHCP

MN

Network 1 (802.11) Network 2 (802.11)


PANA (Pre-Authentication and pre-configuration to obtain IP1)

CN

Data

Data

Tunnel (IP0-IP1) -

-SIP Re-invite with IP1

Data

AddressacquisitionUsing DHCPrelay

R1

Network 3

-

-

Deletes Tunnel with PANA Update


Assign IP1 to TunnelI/F

L2 handover

Packet loss period

DHCP

IRT Talkl - 51

MPA Experimental Flow (proactive handoff)

R2MNCNDHCP

RTP

PANA DHCP

PANA (ACK)

SIP Re_INVITE (IP1)8.913

9.030

9.136

RTP (39835)

OK

ACK

9.267

19.283

19.285

19.291

HandoffDecision

PANA Trigger to delete tunnel

RTP (40335)

RTP (40336)19.29819.31519.379

RTP (40340)

IWCONFIG (IOCTL) RTP (40341)19.39319.394 JOIN19.408 JOIN (ACK)

(Auth/Assoc, ifconfig, route,)

L2 handoff+ local L3Configuration

PANA Response

RTP (40342)

BU

19.411

MNNetwork 1

Network 2 Network 3

First packet in new network (non-tunneled)

19.395 Lost packet (non-tunnel)

DHCP(IP1)

RTP

RTP

Tunnel deleted

RTP

X

Tunneled Data

NoPackets lostDuring BU

Tunnel Setup

Signal

RTP Data

Lost RTP Data

Tunneled packet

RTP (40337)

OK (tunneled)

RTP packetsSpaced ~16 ms

IP0

IP1

IRT Talkl - 52

Optimized handoff delay (Single IF/ Multiple I/F)

Figure 3: Multi-Interface with MIP (802.11-CDMA)

Figure 5: Proactive with SIP mobility (Single Interface 802.11-802.11)

802.11 CDMA 802.11 CDMA

Figure 4: Multi-Interface with SIP (802.11-CDMA)

802.11 CDMA

4 s 4 s

IRT Talkl - 53

Fast-handoff for Multicast Stream (General Scenario)

Internet

Home Network

HA

MN

Visited Network 1

DHCP

MN

Multicast Tree

Visited Network 2

MN

MR1 MR2

DHCP

Handover

New

Multicast Tree

Source

IRT Talkl - 54

Multicast Mobility with multiple servers

S1 S2p1 p2

BS0BS1

Sources

Backbone

Ad server

LocalServer

m1

m2

LocalProgram

RTSP

Ad server

LocalServer

m1

m2

LocalProgram

RTSP

BS2

M-Proxy

(P1,a1) (P2,a2)P2,a2

P2,a3

S0

S1

(a1,a2)

(a3)

• Fast-handoff for the mobiles

RTCP

IGMP

Objective: Reduce Join/Leave Latency during Mobile’s movement

IRT Talkl - 55

Layer 2 Handoff for Multicast

0

1

2

3

4

5

0 200 400 600 800

Time in Seconds

Pro

toc

ols RTP

DRCP

Router Query

Q.Response

IGMP-802.11 (Subnet) Handoff

0

1

2

3

4

5

0 200 400 600 800 1000

TIme in Seconds

Pro

toc

ols

In

sta

nc

e a

t M

ob

ile

RTP

DRCP

Router Query

Q.Response

JOIN Latency JOIN Latency

Subnet handoff

Subnet handoff

Ping-Pong Ping-Pong

There is no JOIN Latency but Leave latency inherent JOIN Latency is about 60 seconds

Proxy assisted subnet handoff

0

1

2

3

4

5

0 200 400 600 800

Time in Seconds

Pro

toc

ols

at

mo

bil

e

RTP

DRCP

Router Query

Q.Response

JOIN latency is almost zeroLeave latency is still an issue

LEAVE latency during 802.11subnet handoff

0

1

2

3

4

5

120 180 240 300 360 420 480 540 600

Timr in Seconds

Pro

toc

ols RTP

DRCP

Router Query

Ping Mobile

Maximum leave latency is about 3 min.

Leavelatency

IGMP Join/Leave latency vs. Proxy-based handoff in 802.11 environment

IRT Talkl - 56

Conclusions

Rapid Handoff in an IP-based cellular network has adverse effect for interactive and streaming traffic

– Introduces delay, jitter and packet loss Experimental results were presented involving handoff between

homogeneous and heterogeneous access networks– 802.11-802.11, 802.11 – CDMA

Both SIP-based and MIP-based mobility were used for experiment Optimized Handoff Schemes were presented with some results for

each scheme Optimized handoff schemes seem to be more prominent for

– Proactive Handover– When the distance between CH and MH is much larger– Proxy-based handoff for multicast stream

Future Work– Comparison with other fast-handoff mechanisms– Network Selection/Discovery Mechanism– Buffering Scheme for MPA assisted handoff

Fast-handoff Mechanisms for Wireless Internet Presenter - Ashutosh Dutta 04/12/2005 IRT Group...

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Transcript of Fast-handoff Mechanisms for Wireless Internet Presenter - Ashutosh Dutta 04/12/2005 IRT Group...