1

NEMO-Enabled Localized MobilitySupport for Internet Access in

Automotive ScenariosIgnacio Soto, Carlos J. Bernardos, Maria Calderon, and

Albert Banchs, University Carlos III of Madrid

Arturo Azcorra, University Carlos III of Madrid and IMDEA Networks

IEEE Communications Magazine, 2009

2

Outline

• Introduction• Overview of Major Existing Approaches• N-PMIPv6 Architecture• Performance Evaluation• Conclusion

3

Introduction

• ubiquitous Internet access• people in modern cities spend a lot of time in vehicles• Users demand the ability to keep their ongoing

communications while changing their point of attachment to the network as they move around– E.g., when a user leaves a coffee shop and gets on a bus– buses that move between pavilions at a fair or – a train that moves from one terminal to another at an airport

• 3G suffers from a number of drawbacks, – Capacity constraints from the point of view of the operator, – cost issues from the end-user perspective

4

Introduction (cont’d)

• NEtwork MObility (NEMO) – developed by the Internet Engineering Task Force (IETF)– Mobile Router (MR)

• located in the vehicles, • handle the communication with the fixed infrastructure and • provide access to passengers’ devices

– using a convenient short-range radio technology

• Users also move from vehicles to fixed platforms

5

Introduction (cont’d)

• Network-based Localized Mobility Management (NetLMM)– allows conventional IP devices to benefit from this mobility

support• allows operators to provide mobility support without depending on

software and complex mobility related configuration in the terminals

– Proxy Mobile IPv6 (PMIPv6)• developed by the Internet Engineering Task Force (IETF)• has the limitation of not fully supporting mobile networks

6

Overview of Major Existing Approaches

• Network-based Localized Mobility• Network Mobility Support• The current Solution for Combing NEMO and PMIPv6

7

Network-based Localized Mobility

• Mobile Access Gateway (MAG)– usually the access router– responsible for tracking the

movements of the MT in the access link

– performs the mobility-related signaling on behalf of an MT• Proxy binding update (PBU)

• Local Mobility Anchor (LMA)– within the backbone network– maintains a collection of routes

for individual MTs• Proxy binding acknowledgment (PBA)

– Packets for an MT are routed to and from the MT through tunnels between the LMA and the corresponding MAG

8

access authentication

Ki-Sik Kong, Wonjun Lee, Youn-Hee Han, Myung-Ki Shin and HeungRyeol You, “Mobility Management for All-IP Mobile Networks: Mobile IPv6 vs. Proxy Mobile IPv6,” IEEE Wireless Communications, 2008.

9

Network Mobility Support

• the mobile network prefix (MNP)– In NEMO basic support, the mobile network has configured

addresses belonging to one or more address blocks assigned to the home network

• when the mobile network is away from home, packets addressed to the mobile network nodes (MNNs) still will be routed to the home network

10

InternetInternet

HA_MN

HA_MR

CN_MN

1::

2::

4::

3

MN

2

BU

4::2->7::2

5::/prefixlen,6::/prefixlen forward to MR

7::

MR

LFRLFN

6::

5::

2

NEMO basic operation

11

InternetInternet

HA_MN

HA_MR

CN_MN

1::

2::

4::

3

MN

2

4::2->7::2

5::/prefixlen,6::/prefixlen forward to MR

7::

MR

LFRLFN

6::

5::

2

MN

2

BU

1::2->6::2

1::2->6::2

NEMO basic operation

12

The current Solution for Combing NEMO and PMIPv6

• the NEMO and NetLMM solutions can be combined in an integrated architecture.– Transparent network mobility support: MRs manage the

mobility of a network composed of a set of devices moving together.

– Transparent localized mobility support without node involvement: MRs and MTs can roam within a PMIPv6 domain without changing their IP addresses.

• this combination does not constitute a full integration – an MT cannot roam between an MR and a MAG of the fixed

infrastructure without changing its IP address.– MTs are required to run MIPv6 to manage mobility (that is, the change

of IP address) by themselves

13

N-PMIPv6 Architecture

• The key idea of N-PMIPv6 consists in extending the PMIPv6 domain to also include mobile networks.– Both the fixed infrastructure (i.e., MAGs) and the mobile

networks (i.e., MRs=mMAGs) belong to the same network operator.• MRs require functionality to extend the PMIPv6 domain to mobile

networks

• manages the mobility of an mMAG in the same way that PMIPv6 manages the mobility of an MT

• an MT that attaches to a mobile network is not required to change its IPv6 address.

14

15

16

• MT handover (getting off the vehicle)

17

Performance Evaluation

18

• Experiments were performed through simulations with the OPNET tool.– TCP data transfer– 20 MB data file from the CN to the MT– Measuring the average throughput

19

Performance Evaluation (cont’d)

• video streaming– transmits video over Real Time Protocol/User Datagram

Protocol (RTP/UDP)– streamed from one PC to another, crossing a third PC.

• The iptables software was configured in the third PC to introduce interruptions of – a duration and frequency equal to the ones caused by handovers (for the

usual case 10 ms)

• 16 real users assessed the subjective video quality they perceived for each experiment– Following the International Telecommunication Union (ITU)

recommendations

20

involved an unfortunate drop of some key packets

21

Conclusions • provide an overview of the major existing approaches to

support mobile networks in network-based, localized mobility domains

• N-PMIPv6, – Design prefix delegation mechanism in the NetLMM domain– Design PBU flag for MR, binding cache look up– Nested tunnel: LMA = MAG - mMAG

• the experimental and simulation results show that the performance of combination NEMO+MIPv6+PMIPv6 is substantially worse

• Future plans include the implementation of N-PMIPv6– the experimental evaluation of the state and processing overhead in

the nodes of the architecture.

22

comments

• Multiple tunnels between the MAG of the mMAG and the LMA– HA-MR + LMA-MAG + LMA-mMAG

• Proxy Mobile IPv6 requires that the link between the MT and the MAG is a Point-to-point link– WiFi?– Might be work on femtocell

• Session continuity– When getting on a vehicle

• The user (MT) might not be necessary to handover to the MR– Until he/she has terminated the session

– When getting off a vehicle• Need to reconnect …