Master Thesis Presentation

“Simulating mobility in a realistic networking environment”

Supervisor : George PolyzosExaminer : George Xylomenos

Student : Dimitrios Charoulis

Introduction

Early days of the Internet:• government-funded research network on top of PSTN• “overlay” that complemented the PSTN infrastructure by adding

packet-switching• goal was to support the needs of researchers (file transfer)

Internet Evolution:• mass market platform new needs

– bandwidth –hungry applications– real-time constraints– content evolution– portable networking devices

Why Mobility ?Mobility : not to lose connection in application level while changing network interface

At first there was no provisioning for mobile users.• great evolution of wireless technologies• increase of portable devices• increase of wireless networksneed to keep portable devices connected

Mobility issues in IP :• Dual role of IP addresses

– Identification of location and end-host id• Unicast routing

Mobility offered as an “add-on” with protocol enhancements

What’s new with IPv6

• Flexible header size– one or more extension headers may be used to include

additional information– extension headers have one or more options

• Interfaces may have more than one registered addresses• Stateless/Serverless address autoconfiguration (except for

statefull address configuration, i.e. DHCPv6)

Mobile IPv6 (MIPv6)

Internet

Foreign Network

Home Network Correspondent’s Network

Home AgentHA_BC

CN_BC

MN_BUL

Binding Cache:Home-Address Care-of-Address

Binding Update List:HoA, CoA Destination

Assign Home-AddressMN detects movement & forms a new CoASend Binding Update to HA

MN_BUL

HoA CoA HA

HA processes BU, updates BC & sends a Binding Acknowledgement

HA_BC

HoA CoA

Tunnel between HA and MN

At first place traffic towards MN comes through HA TRIANGLE ROUTING

Return Routability Procedure

CN_BC

HoA CoA

If BU valid update BC and send BA to MN

MN_BUL

HoA CoA HA

HoA CoA CN

Hierarchical Mobile IPv6 (HMIPv6)

Internet

Foreign Network

Home Network Correspondent’s Network

Home Agent

Mobile Anchor Point

MN_BUL

HA_BC CN_BC

MAP_BC

Assign Home-AddressIn new MAP domain configure two CoAs :• On-Link-Care-of-Address (LCoA)• Regional-Care-of-Address (RCoA)

Send BU to MAP

MN_BULRCoA LCoA MAP

MAP_BC

RCoA LCoA

Send BU to HA

HA_BC

HoA RCoA

MN_BULRCoA LCoA MAP

HoA RCoA HA

Return Routability Procedure

CN_BC

HoA RCoA

MIPv6 Vs HMIPv6MIPv6 HMIPv6

Handles micro- and macro- mobility the same way

Separates micro- from macro - mobility

Not suitable for recent handovers Good performance in micro-mobility handovers

No special requirements in foreign network architecture

Requires Mobile Anchor Point and Access RouterMay be used only for micro-mobility purposesReduces signaling overhead to core network

Simulation scenario topology

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Simulation scenario parametersParameter ValueNumber of Mobile Nodes 10(10)…90

Number of Correspondent Nodes 10(10)…90

Wired connections bandwidth 100 Mbps & 10 Mbps

Propagation delay in core links 2ms

Propagation delay in network link 0,3ms

Type of traffic UDP

Data rate 135 Kbps

Packet size 256 Bytes

Simulation results I

• HMIPv6-S1 outperforms MIPv6 (on average 12,5% more handovers)• When #MNs > 60, HMIPv6-S2 performs worst than other HMIP scenarios

10 20 30 40 50 60 70 80 900

50

100

150

200

250

300

350

Total Number of Handoffs

MIPv6HMIPv6-S1HMIPv6-S2HMIPv6-S3

Num of MNs

Num

of H

ando

ffs

Simulation results II

10 20 30 40 50 60 70 80 900

200

400

600

800

1000

1200

1400

1600

1800

2000

Total L3HandoverLatency

MIPv6HMIPv6-S1HMIPv6-S2HMIPv6-S3

Num of MNs

Tim

e (s

ec)

• When #MNs >60, HMIPv6-S1 and HMIPv6-S2 performance resembles MIPv6 ‘s Datagram encapsulation/decapsulation processing-overhead on few MAPs

reaches wired link delay and packet processing in core routers HMIPv6-S3 outperforms MIPv6 every time

Simulation results III

10 20 30 40 50 60 70 80 900

20000

40000

60000

80000

100000

120000

140000

Total L3HandoverPacketLoss

MIPv6HMIPv6-S1HMIPv6-S2HMIPv6-S3

Num of MNs

Num

of p

acke

ts

• Change in L3HandoverLatency does not imply a proportional change in L3HandoverPacketLoss

• Again when #MNs increases over 60, HMIPv6-S1 and HMIPv6-S2 lose their advantage over MIPv6

Simulation results IV

1 2 3 4 5 6 7 8 90

50

100

150

200

250

300

350

400

Number of BUs to the Home Agent

MIPv6HMIPv6-S1HMIPv6-S2HMIPv6-S3

Num of MNs

Num

of B

Us

HMIPv6 reduces signaling towards HA and MN as most times MAP is the only entity to be informed.

Though signaling inside network is slightly increased ( BU HA goes with BU MAP)

Thank you !

Appendix

UNC campus network topology