Project description

In today's ad hoc networks, routing is primarily concerned with connectivity. Present protocols use source- or hop-by-hop-routing, typically characterizing the network with a single metric such as hop count and use shortest path algorithms to select routes.

Our goal is to introduce metrics like capacity, delay, jitter, cost, loss probability, etc, in routing consideration with particular interest in IEEE 802.11-style MAC protocols due to their popular deployment in realistic wireless systems.

The major problems are the:

• Interferences: flows that traverse the same geographical vicinity contend for the same wireless channel capacity;
• Buffer size: After the saturation point the ad hoc network performance decreases;
• Mac queuing time and service time based on the IEEE 802.11 binary exponential backoff algorithm;
• Mobility.

QOLSR = QoS + OLSR

QOLSR is a QoS extension introduced to the OLSR protocol. Almost no additional control traffic is generated (only augmented HELLO and TC messages). Like in standard OLSR, link state information is generated only by nodes selected as MPRs. This information is then used for route calculation. QOLSR requires only partial link state to be flooded in order to provide optimal paths in terms of application requirements. QOLSR does not require any changes to the format of IP packets, thus any existing IP stack can be used and the protocol only interacts with kernel routing table management.

First IETF manet drafts have been submitted as experiments and research go on.

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