Search results for "network protocols"
showing 3 items of 3 documents
Understanding 802.11e contention-based prioritization mechanisms and their coexistence with legacy 802.11 stations
2005
The IEEE 802.11e task group has reached a stable consensus on two basic contention-based priority mechanisms to promote for standardization: usage of different arbitration interframe spaces and usage of different minimum/maximum contention windows. The goal of this article is to provide a thorough understanding of the principles behind their operation. To this purpose, rather than limit our investigation to high-level (e.g. throughput and delay) performance figures, we take a closer look at their detailed operation, also in terms of low-level performance metrics (e.g., the probability of accessing specific channel slots). Our investigation on one hand confirms that AIFS differentiation prov…
On the Fidelity of IEEE 802.11 commercial cards
2006
The IEEE 802.11 D CF protocol is known to be fair in terms of long-term resource repartition among the contending stations. However, when considering real scenarios, where commercial 802.11 cards interact, very unpredictable as well as sometimes surprising behaviors emerge. Motivation of this paper is to investigate the reasons of the very evident disagreement between the theoretical IEEE 802.11 DCF protocol models and its practical implementations. Inparticular, we try to characterize the card behavior not only in terms of perceived throughput, but also in terms of low-level channel access operations. In fact, the simple throughput analysis does not allow to identify what affecting paramet…
Application of Zero Exclusion Condition to Stability Analysis of Computer Networks
2016
Stability, or robust [Dscr ]-stability analysis of computer network considered as a dynamic system, relies on increasing the speed of data transmission while minimizing the queuing time delays of its packets in the router buffers that can affect the overall data flow of the network traffic. We consider a zero exclusion condition as an effective method for testing and analyzing the computer networks stability. Our findings indicate that keeping control over the queuing time delays as well as including some factors of the RED algorithm and its variants, which we present in this paper, can improve the quality of network services significantly. Our method can be applicable both to single-loop a…