Traffic Balancing in Wireless MESH Networks
Xiaojing Tao, Thomas Kunz, David Falconer | |
Systems and Computer Engineering | |
Carleton University | |
tkunz@sce.carleton.ca |
Traffic in Wireless MESH:
Potentially Unbalanced
Explained in previous presentation for MANETs | |
Nodes measure medium busy time, decide whether node is in congested area based on dynamically determined threshold | |
Sender picks route to destination (here: one of the gateways) that has lowest number of overloaded nodes | |
To route towards a node in a MESH: have to trigger router discovery from ALL gateways (or have destination trigger “reverse” route discovery to all gateways) |
Simulation Results I:
2 Gateways, high mobility
Simulation Results
II:
2 Gateways, low mobility
Interesting Issue: Gateway/AP Location
Performance vs. Gateway Location
Mesh networks: Gateways/APs are performance bottlenecks | ||
MANET routing protocols, routing to closest AP, tend to (temporarily) overload some APs | ||
TB can improve network performance by distributing traffic more equally to all APs | ||
Future Work: | ||
Location of APs has major impact on performance | ||
IEEE 802.11 is poor protocol for APs, as they need to access media more frequently than nodes | ||
MESH are more static, should we re-issue route discovery periodically? | ||
Explore TB in our wireless mesh testbed, based on IEEE 802.11 a/g radios and Intel IXP 425-based wireless routers |