Lakshmi Narasimhan Kannan

Learn More
This paper presents an analytical model which extends Markov Chain models previously proposed for IEEE 802.11 data link protocol. Unlike already published models, the proposed Markov Chain accounts jointly for the following three factors. First, in addition to collision, it accounts for frames that may be lost due to a low signal-to-noise ratio value at the(More)
The study in this paper investigates the use of (single-hop) cooperative medium access control (MAC) protocols in multi-hop radio networks. The objective is to assess whether the cooperative MAC protocols available in literature can improve performance in multi-hop ad hoc networks. A simulation based comparison is carried out in order to evaluate the(More)
Cooperative link layer protocols are typically used in single hop networks to enhance the link layer capabilities using a special node, called relay. In multi-hop networks, a frame is sent from an original source to the final destination through a series of intermediate nodes. The performance benefits of cooperation at link layer can be channeled into(More)
Cooperative link layer protocols are typically used in single hop networks. In such protocols, a special node called the relay node helps deliver frames from a source to a destination. The performance benefits of cooperation at link layer can be streamlined into multi-hop networks as well. In multi-hop networks, a frame is sent from an original source to(More)
— In cooperative link layer protocols the use of relay nodes may increase the capacity of the radio links. The study in this paper investigates what (if any) performance gain may be passed onto the routing protocol of a mobile ad hoc network. Two popular routing protocols are considered, AODV and OLSR, as each provides a unique route acquisition mechanism.(More)
— This paper combines multi-hop networking with single-hop cooperative communications. The solution is built upon the standard IEEE 802.11 protocol operating in the ad hoc mode. A simulation based comparison is carried out in order to evaluate the performance gains and benefit of cooperative communications applied to multi-hop networking. Preliminary(More)
In this paper the authors present an analytical model that — compared to previously published work — more accurately captures the delay of IEEE 802.11 protocol under low, medium, and near-saturation load conditions. A Markov chain is used to keep track of the instantaneous number of (active) nodes that have a frame to transmit. One advantage(More)
— This paper investigates the use of cooperative communications in the context of ad hoc IEEE 802.11b to combat radio signal degradations due to slow fading. The performance gain of both an existing cooperative protocol and the one proposed in the paper is discussed. It is quantitatively shown how much the two cooperative protocols increase throughput,(More)
  • 1