Access Restriction

Author Stavrakakis, Ioannis ♦ Oikonomou, Konstantinos
Source CiteSeerX
Content type Text
File Format PDF
Language English
Subject Domain (in DDC) Computer science, information & general works ♦ Data processing & computer science
Subject Keyword Simple Probabilistic Policy ♦ Prior Configuration ♦ Analytical Study ♦ Enhanced Version ♦ Specific Transmission ♦ Heavy Tra Condition ♦ Assigned Scheduling Time Slot ♦ Suitable Range ♦ Ad-hoc Environment Konstantinos Oikonom Ou ♦ Ad-hoc Network ♦ Simple Topology Density ♦ Non-assigned Slot ♦ Minimum Guaranteed Throughput ♦ Topology Density ♦ Simulation Result ♦ Topology Unaware Tdma-based Scheme ♦ Deterministic Policy ♦ Probabilistic Policy ♦ Cient Medium Access Control ♦ Collision-free Transmission ♦ Access Probability
Description The design of an e#cient Medium Access Control (MAC) is challenging in ad-hoc networks where users can enter, leave or move inside the network without any need for prior configuration. Chlamtac and Farago have proposed a topology unaware TDMA-based scheme, suitable for ad-hoc networks, while Ju and Li have proposed an enhanced version that maximizes the minimum guaranteed throughput. Both approaches consider a deterministic policy for the utilization of the assigned scheduling time slots. In this work it is shown that this deterministic policy fails to utilize non-assigned slots that would result in collision-free transmissions even under heavy tra#c conditions. A simple probabilistic policy is proposed, capable of utilizing the non-assigned slots according to an access probability, fixed for all users in the network. An analytical study establishes the conditions under which the probability of success for a specific transmission under the probabilistic policy, is higher than that under the deterministic. The dependence of both policies on the topology density is shown and a simple topology density metric is introduced as well. Simulation results show that there exists a suitable range of values for the access probability for which the probabilistic policy outperforms the deterministic and show how this range is a#ected by the variations of the topology density.
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Research
Education Level UG and PG ♦ Career/Technical Study
Learning Resource Type Article
Publisher Date 2003-01-01
Publisher Institution Personal Wireless Communications (PWC 2003