Following this, any maintenance regions are scheduled first as indicated in , and then the minislots that are to be used during contention access (for bandwidth request transmissions) are scheduled, using a Contention Slot Allocator (CSA).
Performance Evaluation of Adaptive Contention Slot Allocators for CATV Networks based on the European Cable Comms.
4 Mbps Minimum contention slots per UL-frame (c) 7 slots UL minislot size 16 bytes UL-frame Duration (F) ([approximately equal to] 2ms) 150 minislots Simulation time for each run 60s Distance from nearest/farthest SS to the BS 0.
In general, backoff algorithms can be characterized by three key measures: the expansion/reset factor of the contention window, the probability distribution of contention slot selection, and the update mechanism of the contention window's bounds.
Schemes in  and  use non-uniform probability distribution for contention slot selection over the optimized contention window.
Let us further assume that x [greater than or equal to] 2 number of STAs from the group select the same contention slot [j.
However, there is a slight difference in the contention slot selection process.
For example, if a STA that is in its i-th contention stage experiences a collision, while contending by selecting the contention slot j [member of] [0, [W.
Hence, it would be safe (in terms of collision avoidance) not to select any of the contention slots in the overlapped region.
In this paper, we propose a reactive BEB which deterministically nullifies the selection chances of the overlapped contention slots in the adjacent contention stages.