DDR-based Multicast routing Protocol with Dynamic Core (DMPDC) Shiyi WU, Navid Nikaein, Christian BONNET Mobile Communications Department EURECOM Institute, France

Outline Introduction Our Contribution: General Scheme Basic – DDR - Distributed Dynamic Routing Algorithm – MRDC - Multicast Routing protocol with Dynamic Core DDR-based Multicast routing Protocol with Dynamic Core (DMPDC) Conclusions

Introduction - MANET Definition – A collection of wireless mobile nodes forming an autonomous, dynamic, temporary networks without infrastructure or centralized administration. Applications – Military communication, – Emergency search and rescue operations, – Communication set-up in conferences/meetings/lectures Basic problem: Routing – Infrastructure-less – Node movements – Bandwidth limitation

Multicast routing in MANET Tree structure v.s. Mesh structure Source-oriented v.s. Group-shared – Source-oriented: one structure per source Can use different metrics but expensive in bandwidth consumption – Group-shared: one structure per group Less routing overhead but not efficient in data transmission R1R1 R2R2 S R1R1 R2R2 S

Applications Network  Topology Creation With respect to Network Properties  Route Determination With respect to Application Requirements Routing # of nodes, frequency of E2E connection & of topology changes Contribution: General Scheme unicastDMPDC DDR

Network Topology Forest TREE TREE …. TREE ZONE ZONE …. ZONE DDR TIME BEACON

MRDC Construct and maintain a multicast tree on-demand, the root of tree (core) is the first source of a multicast session Tree construction – Core broadcasts Core Advertisement so that nodes know multicast session start. – Group members run RAR/RAA procedure to join multicast tree. Group members send Route Activity Request (RAR) message Tree members reply Route Activity Ack (RAA) to confirm the request Tree maintenance – Local route recovery tries to re-establish connection between two tree members immediately. – Periodical tree refreshment re-construct multicast tree to adapt network topology.

DMPDC - Basic ideas Modify MRDC to adapt the infrastructure offered by DDR in order to – Improve bandwidth efficiency – Speed up link error detection and recovery – Increase packet delivery ratio Use DDR’s forest to broadcast Core Advertisement message Use DDR’s intra-zone routes – Reduce multicast tree maintenance cost – Benefit from DDR’s periodical intra-zone route update

Topology Creation Under DDR DDR

Multicast tree in DMPDC

Multicast tree Tree vertices – Group members – Gateway nodes Tree edges – Bridges (active inter-zone connection) which are maintained by DMPDC – Intra-zone routes which are updated by DDR

Tree maintenance Periodical tree refreshment – Core periodically sends Core Advertisement message to delete old active inter-zone connection – Group members run RAR/RAA procedure to activate inter-zone connection according to topology Local route recovery – When a tree member loses route to its downstream. – Among neighboring zones

Conclusions  What we gained:  Share routing information with other routing protocol through DDR  Neighborhood  Local area topology  Spanning tree for broadcast  Adapt to network topology  Reduce the necessity of periodical tree refreshment  Reactive tree construction and proactive tree maintenance  Performance Evaluation under various condition

Multicast tree under MRDC Other source(s) m p o n q a b c e g f j i k l r Receiver First source (core) h d Wireless Link Tree edge Tree member Flow from node h Flow from node d