Self-organizing TDMA MAC protocol for effective capacity improvement in IEEE 802.11 WLANs

This paper presents a MAC protocol named selforganizing time division multiple-access (SO-TDMA) aiming to enable quality-of-service (QoS) provisioning for delay-sensitive applications. Channel access operation in SO-TDMA is similar to carrier-sense multiple-access (CSMA) in the beginning, but quickly converges to TDMA with an adaptive pseudo-frame structure. This approach has the benefits of TDMA in a highload traffic environment, while overcoming its disadvantages in low-load, heterogeneous traffic scenarios. Furthermore, it supports distributed and asynchronous channel-access operation as in CSMA. These are achieved by dynamically adapting the transmission opportunity duration based on the common idle/busy channel state information acquired by each node through learning, without explicit message passing. Performance comparison of CSMA, TDMA, and SO-TDMA in terms of effective capacity, system throughput, and collision probability is investigated

Self-Organizing TDMA MAC Protocol for Effective Capacity Improvement in IEEE 802.11 WLANs

This paper presents a MAC protocol named selforganizing time division multiple-access (SO-TDMA) aiming to enable quality-of-service (QoS) provisioning for delay-sensitive applications. Channel access operation in SO-TDMA is similar to carrier-sense multiple-access (CSMA) in the beginning, but quickly converges to TDMA with an adaptive pseudo-frame structure. This approach has the benefits of TDMA in a highload traffic environment, while overcoming its disadvantages in low-load, heterogeneous traffic scenarios. Furthermore, it supports distributed and asynchronous channel-access operation as in CSMA. These are achieved by dynamically adapting the transmission opportunity duration based on the common idle/busy channel state information acquired by each node through learning, without explicit message passing. Performance comparison of CSMA, TDMA, and SO-TDMA in terms of effective capacity, system throughput, and collision probability is investigated

Self-organizing TDMA: a distributed contention-resolution MAC protocol

This paper presents a self-organizing time division multiple access (SO-TDMA) protocol for contention resolution aiming to support delay-sensitive applications. The proposed SOTDMA follows a cognition cycle where each node independently observes the operation environment, learns about the network traffic load, and then makes decisions to adapt the protocol for smart coexistence. Channel access operation in SO-TDMA is similar to carrier-sense multiple-access (CSMA) in the beginning, but then quickly converges to TDMA with an adaptive pseudo-frame structure. This approach has the benefits of TDMA in a highload traffic condition, and overcomes its disadvantages in lowload, heterogeneous traffic scenarios. Furthermore, it supports distributed and asynchronous channel-access operation. These are achieved by adapting the transmission-opportunity duration to the common idle/busy channel state information acquired by each node, without any explicit message passing among nodes. The process of adjusting the transmission duration is modeled as a congestion control problem to develop an additive-increasemultiplicative-decrease (AIMD) algorithm, which monotonically converges to fairness. Furthermore, the initial access phase of SO-TDMA is modeled as a Markov chain with one absorbing state and its required convergence time is studied accordingly. Performance of SO-TDMA in terms of effective capacity, system throughput, collision probability, delay-outage probability and fairness is investigated. Simulation results illustrate its effectiveness in performance improvement, approaching the ideal case that needs complete and precise information about the queue length and the channel conditions of all nodes