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Bandwidth Management Framework for IP based Mobile Ad Hoc Networks Khalid Iqbal (41152190) Supervisor: Dr. Rajan Shankaran ITEC810 June 05, 2009 Problem Statement “Incorporating scalable bandwidth management scheme in an IP based mobile ad hoc network environment” Mobile Ad Hoc Networks 2 Agenda IP based Mobile Ad Hoc Network MANET Applications Quality of Service (QoS) MANET Routing Protocols QoS Models Existing QoS models in MANET environment QoS models designed for MANETs Ad Hoc Extensions for ASAP Mobile Ad Hoc Networks 3 IP based Mobile Ad Hoc Networks (MANET) Collection of wireless nodes Connected through wireless links Free to move, Self-configuring No pre-existing infrastructure Dynamic topology Distributed operations Mobile Ad Hoc Networks 4 IP based Mobile Ad Hoc Networks (MANET) Mobile Ad Hoc Networks 5 MANET Applications Military battlefield Commercial Level Disaster relief efforts (flood, earthquake) Local Level Class room network Home network Mobile Ad Hoc Networks 6 Quality of Service (QoS) Capability of a network to provide better services to selected network traffic. Need for QoS in MANETs: Bandwidth management Resource management Application requirements Applications QoS Requirements Email, File Transfer Very tolerant of delay: low Real Audio Very sensitive to delay: High Streaming Video Very sensitive to delay: High Mobile Ad Hoc Networks 7 MANET Routing Protocols Proactive or Table-driven protocols Reactive or On-demand protocols Maintain routing information Waste of bandwidth Immediate availability of routing information No routing table Path calculation before transmission Less overhead, slower Hybrid protocols Combination of both Zone organization Within zone proactive scheme Outside reactive scheme Mobile Ad Hoc Networks 8 QoS Models Integrated Services (IntServ) Management and packet scheduling on a per flow basis Difficult and costly for the routers Differentiated Services (DiffServ) QoS control on a service class basis QoS is invoked on packet-by-packet basis Feasible and cost-effective Mobile Ad Hoc Networks 9 QoS Models Integrated Services (IntServ) Mobile Ad Hoc Networks 10 QoS Models (Cont.) Differentiated Services (DiffServ) Mobile Ad Hoc Networks 11 Existing QoS models in MANET environment (Limitations) IntServ in MANETs Scalability Protocol phases Connection establishment, maintenance, teardown DiffServ in MANETs SLA traffic conditioning rules, placed at the nodes Ambiguous core network Mobile Ad Hoc Networks 12 QoS models for MANETs Flexible QoS Model for Mobile Ad Hoc Network (FQMM) Hybrid per-flow and per-class provisioning Nodes have dynamic role FQMM Limitations Scalability problem Fail to satisfy hard QoS requirements. Mobile Ad Hoc Networks 13 QoS models for MANETs (Cont.) Adaptive Reservation and Pre-allocation QoS Architecture (ASAP) For Infrastructure based networks Soft/Hard Reservation QoS Monitoring Periodic investigation more frequent monitoring, if the network is unstable Mobile Ad Hoc Networks 14 Limitations of ASAP Flow Restoration Problem Flow restoration can be quite long Detecting a missing reservation. Reverse Path Problem Outdated paths unsymmetrical paths Mobile Ad Hoc Networks 15 Solutions to address ASAP problems Local Repair Dynamic Virtual Path Flexible Timing Control Congestion Control Mobile Ad Hoc Networks 16 Solutions to address ASAP problems (Cont..) Local Repair Flow path broken because of dynamic topology No QoS guarantee from broken point to destination Quick repairing mechanism local repair triggered by a soft reservation message Upon receiving a SR message, node reserves some bandwidth Dynamic Virtual Path Unsymmetrical routes Mobile Ad Hoc Networks 17 Solutions to address ASAP problems (Cont..) Flexible Timing Control SR (Soft Reservation) sending interval and the soft state time-out period. Stable network - Large SR interval Coherent; SR and soft state time-out period too large soft state time-out will keep reservations on Mobile Ad Hoc Networks 18 Solutions to address ASAP problems (Cont..) Congestion Control Queue length is not a valid indication Congestion detection by monitoring the wireless channel Approximation of the bandwidth usage Increase or decrease transmission throughput Mobile Ad Hoc Networks 19 ? Mobile Ad Hoc Networks 20