802.11ah MAC Timings
What are MAC timings in 802.11ah?
MAC timings define the time intervals and delays used to coordinate wireless transmissions and acknowledgments.
Why are MAC timings important in 802.11ah?
They ensure collision avoidance, fair access, and efficient use of the wireless medium, especially for low-power IoT devices.
What is the Short Interframe Space (SIFS) in 802.11ah?
SIFS is the shortest waiting time between transmissions, used for immediate responses like ACKs to prioritize timely communication.
What is the Distributed Interframe Space (DIFS) in 802.11ah?
DIFS is the waiting period before a device can attempt to transmit data when the medium is sensed idle.
Does 802.11ah use new interframe spacing values compared to other Wi-Fi standards?
Yes, 802.11ah adjusts timing intervals to optimize for longer range and lower data rates in the sub-1 GHz band.
What is the purpose of Arbitration Interframe Space (AIFS) in 802.11ah?
AIFS sets different waiting times based on traffic priority, enabling Quality of Service (QoS) differentiation.
What is the slot time in 802.11ah MAC timings?
Slot time is the basic unit for backoff intervals, adjusted in 802.11ah to accommodate longer propagation delays.
How is the contention window (CW) used in 802.11ah?
CW determines the range of random backoff slots a device waits before trying to transmit, helping reduce collisions.
How does 802.11ah MAC handle timing for retransmissions?
It waits specific intervals defined by MAC timings before retransmitting frames to avoid repeated collisions.
What is the Role of Clear Channel Assessment (CCA) timing in 802.11ah?
CCA timing determines how long a device senses the channel to ensure it is free before transmitting.
How does 802.11ah timing support power saving?
Timing parameters coordinate sleep and wake cycles to maximize energy efficiency in battery-powered devices.
What timing parameters influence beacon intervals in 802.11ah?
Beacon intervals are set to balance network synchronization and power consumption needs.
How does 802.11ah MAC timing accommodate longer range communication delays?
Timings like slot time and interframe spaces are extended to account for increased signal propagation time.
What is the Extended Interframe Space (EIFS) used for in 802.11ah?
EIFS is used after detecting corrupted frames, allowing the medium to settle before new transmissions.
How do MAC timings affect Quality of Service (QoS) in 802.11ah?
By using differentiated interframe spaces and contention windows, MAC timings prioritize critical data traffic.
Can MAC timings be dynamically adjusted in 802.11ah?
Yes, some timing parameters can be tuned based on network conditions and device capabilities.
What is the impact of longer slot times on network throughput?
Longer slot times reduce collision probability but can slightly decrease overall throughput.
How do MAC timings in 802.11ah support dense IoT deployments?
Timings are optimized to minimize contention and allow many devices to share the medium effectively.
Where can I find detailed timing parameter values for 802.11ah?
They are specified in the IEEE 802.11ah standard documentation under MAC layer timing specifications.
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