Ad Hoc Multicast RoutingAd Hoc Multicast Routing

Category of Ad Hoc Multicast Category of Ad Hoc Multicast Routing ProtocolsRouting Protocols

Underlying Data Delivery Structure

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Flooding-Based Tree-Based Mesh-Based

AMRIS

Hybrid-Based

MAODV

LAM

CAMP

OMDRP

FGMP

MCEDAR

ADB

AMROUTE

Broadcast

Category of Ad Hoc Multicast Category of Ad Hoc Multicast Routing ProtocolsRouting Protocols

State Maintenance

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Unconstrained Stateless Constrained

DDM AMROUTE

PAST-DM

LGT

PBM

POMA

Tree-based scheme

Mesh-based scheme

Flooding - BroadcastingFlooding - Broadcasting

Results in minimal state retention and high reliability which makes it a viable candidate for multicast protocols in very dynamic MANET.

Heavy-handed in terms of overheadObtains the best results in terms of

reliable deliveryProblem

Broadcast storm[12]

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AMRIS: Ad Hoc Multicast Routing AMRIS: Ad Hoc Multicast Routing Protocol Utilizing Increasing Id-Protocol Utilizing Increasing Id-NumbersNumbersOn-demandShared tree

Tree is rooted at special node called Sid (Smallest Id) : one of sources

increasing msm-id (multicast session member id, assigned dynamically)

Initiate a sessionNEW-SESSION msg

(Sid’s msm-id, metrics) Join a session,

unicast JOIN-REQ to its potential parent node

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1111

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2424

3434

2828

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msm-id = Sid = 0

MAODV: Multicast Ad Hoc On-Demand MAODV: Multicast Ad Hoc On-Demand Distance Vector ProtocolDistance Vector Protocol Based on unicast

AODV Discovers multicast

route on-demand using a broadcast route discovery mechanism

Route discoveryRREQ

• To join a group, • or to send to a group if

no route

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ODMRP: On-demand Multicast ODMRP: On-demand Multicast Routing ProtocolRouting ProtocolMesh-based, soft stateForwarding group: a subset of nodes

forwards the multicast packets

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Join query

Join

que

ry

Join query

Join query

Join queryJoin query

Join

que

ry

Join query

Join queryJoin query

Join query

Join reply

Join replyJo

in rep

ly

Join

repl

yJoin reply

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source

receiver

receiver

DDM: Differential Destinations DDM: Differential Destinations MulticastMulticastExplicit Header

All destinations are placed in the packet headers

Data ForwardingReferring underlying unicast routing table

Two modesStatelessSoft state

Membership ManagementSource controls multicast group membership

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LGT: Location Guided TreeLGT: Location Guided TreeA small group

multicast schemes based on packet encapulation

Builds an overlay multicast packet distribution tree on top of the underlying unicast routing protocolUsing the geometric

location information without knowing the global network topology

Construct a tree with geometrically shorter tree edges

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n2

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n1

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Outstanding ProjectsOutstanding Projects

UCLA Wireless Adaptive Mobility Laboratory

Computer Communication Research Group at the University of California, Santa Cruz

Rice University Monarch ProjectWireless and Mobile Ad Hoc Networks at

University of Southern California

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GeocastingGeocasting

Geocast Region – A specified geographical area

A variant of the conventional multicasting problem

Deliver Packets to a group of nodes in Geocast Region.

The location information of all the nodes will be known by GPS

Whenever one node in Geocast region receives message from outside, it will flood it to all its neighbors.

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LBM: Location-based MulticastLBM: Location-based Multicast

Extend LAR for geocastingFlooding approach

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LBM Scheme 1 LBM Scheme 2

VDG: Voronoi Diagram based VDG: Voronoi Diagram based GeocastingGeocasting To enhance the success rate

and decrease the hop count and flooding rate of LBM

Carve up the whole plane into several Voronoi regions based on the source and its neighbor

Only neighbor nodes (B, E) which are in the same Voronoi region as the Geocast Region will be selected to receive the message from Source.

VDG reduces the flooding rates of LBM Scheme 1

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PBM: Position Based MulticastPBM: Position Based Multicast Design Goal

Minimize total hops to all destinationsMinimize length of path to individual destination

Sender has the knowledge (assumptions)Position of destination(s)Position of neighbor(s) It’s own position

Greedy multicast forwardingEach destination exists at least one neighbor which is

closer to that destination than the forwarding node itself.

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K: Forwarding node

N: Set of all neighbors of K

W: Set of all subsets of N

Z: Set of all destinations

d(x,y): distance between x and y

Greedy Multicast Forwarding

min ( , )| |( ) (1 )

| | ( , )m wz Z

z Z

d m zwf w

N d k z

Minimize the expression

No. of neighbors that packet is transmitted

toRemaining distance to all destinations

Energy EfficiencyEnergy Efficiency

Power-Aware and Energy-Efficient Broadcast and Multicast InfrastructureSolution 1: Lifetime of a bottleneck node is

improved by reassigning its farthest children to other nodes in the tree with the goal of improving the lifetime of the multicast tree.

Solution 2: finding a tree with the least consumed power becomes a conventional optimization problem on a graph where the weighted link cost corresponds to the transmission power required for transmitting a packet between the two nodes of the link

Energy Consumption from Retransmission at the Data-Link LayerSolution: maximizing sleep mode operation

supported by the lower level protocol 15