Efficient Flooding in Ad Hoc Networks with Ondemand Passive Clustering

1
Efficient Flooding in Ad Hoc Networks with
On-demand (Passive) Clustering
Yunjung Yi, Mario Gerla and Taek Jin Kwonyjyi,
gerla, tkwon_at_cs.ucla.eduhttp//www.cs.ucla.edu/N
RL/wireless

• Efficient Flooding
• Choose the set of dominant forwarding nodes that
  cover the entire network
• Our Idea
• Use Passive Clustering to construct underlying
  cluster platform
• Only Clusterheads and gateways forward pkts
• On-demand (zero overhead if no user data)

• Flooding
• Broadcast to the whole network or part of it
• Widely used in Ad hoc networks
• Inefficient when the ad hoc network is very dense

ClusterHead
Gateway
Ordinary Node

• Example
• Flooding with 1 source, 4pkts/second data rate,
  100 nodes randomly placed within 1000x 1000 m2

Delivery Ratio (Fraction of Destinations Reached)
Total Rebroadcasts in a single flood
BF Blind Flooding
PC_LID Efficient Flooding with Passive
Clustering
MPR Efficient Flooding with MPR (MultiPoint
Relay)
AC_LID Efficient Flooding with Active Clustering

• Applying Our Idea to AODV
• Efficient Flooding reduces the overhead of route
  queries flooding

D
S
RREQ (Route Request)
RREP (Route Reply)
Drop

• Example
• AODV with/without PC, 2pkts/second data rate
• 100 nodes randomly placed within 1500x 500 m2
• 2-20 m/s mobility

Normalized CTRL OH
Delivery Ratio

• Benefit
• Reduce CTRL OH
• Improve Throughput
• Comments
• PC can be applied to other On-demand routing
  protocols
• E.g., DSR, ODMRP

UCLA CSD Network Research Laboratory
www.cs.ucla.edu/NRL