IPv6 Network Mobility on Ad hoc network IPv6 Network Mobility on Ad hoc network for Transportation Systemfor Transportation System

Assoc. Prof.

Lee Bu Sung, Francis

ContentContent

• PerMoCom – An overview• Network Mobility

– Hierarchical Routing Protocol– Flat Routing Protocol

• Network Mobility using IPv6• Network Mobility using IPv6 with Redirect

Header• Numerical Comparison• Conclusion

PerMoCom: PerMoCom: An OverviewAn Overview

• PerMoCom – Pervasive Mobile Communication for Public Transportation System– consists of segments of Ad hoc network

interconnected via the Internet

PerMoCom:PerMoCom: Ad hoc RoutingAd hoc Routing

A-STAR : Anchor-based Street and Traffic Aware

Routing – M-GRID Mobility Model– Anchor-based Routing

• list of anchors a data packet should pass through

– Spatial Awareness• use of underlying street map for anchor computation

– Traffic Awareness• use of vehicular traffic information to find route with

higher connectivity, thus high delivery possibility

PerMoCom:PerMoCom:Ad hoc RoutingAd hoc Routing

• M-Grid mobility model– Node heterogeneity: bus and taxi– Preferential movement, higher density on bus route– Radio obstacles

           

             

           

             

             

             

40m

400m

PerMoCom:PerMoCom:

Ad hoc RoutingAd hoc Routing

• Achieve Traffic Awareness – Assign weight to the street according to traffic

condition (high traffic less weight) – Least weight path is computed and used as anchor

path– Ways for weight assignment

• Estimate the traffic condition by number of bus lines - statistically rated map

• Dynamically monitor the traffic condition on each street - dynamically rated map

PerMoCom:PerMoCom:Access Router Discovery ProtocolAccess Router Discovery Protocol

• MR knows its GPS position• MR helps to propagate AR information• use beacon of A-STAR to propagate AR information• coverage of AR boundary does not need to be explicitly

defined• Self-adaptable

Network Mobility usingNetwork Mobility using Hierarchical Hierarchical Routing Protocol Routing Protocol

Hierarchical routing– logically separated into subnets– continues the hierarchical architecture of the

Internet – causes the network protocol to enter recursive

nesting when applied to mobile network where MRs from different home networks are interconnected hierarchically with AR as the root connection point to the Internet.

– increase of this recursive nesting results in multi-angular routing issue which is known as pinball routing

Flat routing protocols – regards the ad hoc network as a number of

nodes without subnet partitioning, thus it does not require a hierarchical addressing structure

– MRs are already uniquely identified by their Care-of address (CoA)

– the recursive nesting problem is reduced to a one level nesting

– all MRs are treated as nodes under the subnet of the AR in its home or foreign network and each MR will obtain a set of subnet address from the AR in its home network

Network Mobility usingNetwork Mobility using Flat Routing ProtocolFlat Routing Protocol

Network Mobility usingNetwork Mobility using IPv6 IPv6 Basic ModeBasic Mode

Network Mobility usingNetwork Mobility using IPv6 Basic Mode withIPv6 Basic Mode with

Redirect HeaderRedirect Header۞

Without Redirect Header With Redirect Header

Numerical EvaluationNumerical Evaluation

• Saves 200 bytes• This deduction increases with number

of hops and number of data packets

ConclusionConclusion

• introduced PerMoCom– consists of fleets of mobile routers forming a wireless

network backbone that uses flat routing protocol

• illustrated the mobility support of IPv6 on PerMoCom

• introduced a Redirect Header for the mobility support in IPv6– to reduced the network traffic generated by the

tunnel in tunnel effect when a MNN is attached on a MR link

– works with both Mobile IPv6 Basic Mode and Route Optimisation Mode

– useful in the Mobile Ad Hoc Network cloud where bandwidth is scarce.

Questions Questions and and

AnswersAnswers

Binding Update for Mobile Binding Update for Mobile RouterRouter

Binding Update for Mobile Binding Update for Mobile Network NodeNetwork Node

New Binding Update New Binding Update MessageMessage

• a new bit – “R” in the Binding Update Message• this bit utilised a bit in the 12 bits reserved field• by setting this bit, MNN indicates to its HAMNN or

CN that it supports the Redirect Header

New Binding Acknowledgement New Binding Acknowledgement MessageMessage

• we introduce a new bit – “R” in the Binding Acknowledgement Message using a bit in its reserved field

• HAMNN or CN will reply a Binding Update message with a Binding Acknowledgement with the “R” bit set if they also supports the Redirect Header.

The Redirect HeaderThe Redirect Header

• IPv6 allows optional Internet-layer information to be encoded in separate headers

• placed between the IPv6 header and the upper- layer header in a packet

• used to carry the original destination address for the data packet