Ad Hoc Multicast Routing
Category of Ad Hoc Multicast Routing Protocols Underlying Data Delivery Structure Flooding-Based Tree-Based Mesh-Based Hybrid-Based Broadcast AMRIS CAMP MCEDAR MAODV OMDRP ADB LAM FGMP AMROUTE
Category of Ad Hoc Multicast Routing Protocols State Maintenance Unconstrained Stateless Constrained Tree-based scheme DDM AMROUTE Mesh-based scheme PBM PAST-DM LGT POMA
Flooding - 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 overhead Obtains the best results in terms of reliable delivery Problem Broadcast storm[12]
AMRIS: Ad Hoc Multicast Routing Protocol Utilizing Increasing Id-Numbers msm-id = Sid = 0 On-demand Shared 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 session NEW-SESSION msg (Sid’s msm-id, metrics) Join a session, unicast JOIN-REQ to its potential parent node X 11 14 18 21 24 28 31 38 34
MAODV: Multicast Ad Hoc On-Demand Distance Vector Protocol Based on unicast AODV Discovers multicast route on-demand using a broadcast route discovery mechanism Route discovery RREQ To join a group, or to send to a group if no route
ODMRP: On-demand Multicast Routing Protocol Mesh-based, soft state Forwarding group: a subset of nodes forwards the multicast packets Join query Join reply source receiver
DDM: Differential Destinations Multicast Explicit Header All destinations are placed in the packet headers Data Forwarding Referring underlying unicast routing table Two modes Stateless Soft state Membership Management Source controls multicast group membership
LGT: Location Guided Tree A small group multicast schemes based on packet encapulation Builds an overlay multicast packet distribution tree on top of the underlying unicast routing protocol Using the geometric location information without knowing the global network topology Construct a tree with geometrically shorter tree edges S n5 n4 n6 n2 n3 n1 n7 n8
Outstanding Projects UCLA Wireless Adaptive Mobility Laboratory Computer Communication Research Group at the University of California, Santa Cruz Rice University Monarch Project Wireless and Mobile Ad Hoc Networks at University of Southern California
Geocasting 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.
LBM: Location-based Multicast Extend LAR for geocasting Flooding approach LBM Scheme 1 LBM Scheme 2
VDG: Voronoi Diagram based Geocasting 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
PBM: Position Based Multicast Design Goal Minimize total hops to all destinations Minimize 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 forwarding Each destination exists at least one neighbor which is closer to that destination than the forwarding node itself. 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 Minimize the expression No. of neighbors that packet is transmitted to Remaining distance to all destinations
Energy Efficiency Power-Aware and Energy-Efficient Broadcast and Multicast Infrastructure Solution 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 Layer Solution: maximizing sleep mode operation supported by the lower level protocol