List of PPDUs Supported in 802.11s
What is a PPDU in 802.11s?
PPDU stands for Physical Layer Protocol Data Unit, the basic frame structure used for transmitting data over the wireless physical layer.
How does 802.11s use the PPDU?
802.11s uses the standard PPDU format from base 802.11 PHYs to carry mesh management and data frames without modifying the PPDU structure.
Does 802.11s define a new PPDU format?
No, 802.11s reuses the existing PPDU formats defined in 802.11a/b/g/n standards.
What types of frames does the PPDU carry in 802.11s?
It carries mesh data frames, mesh management frames, and control frames essential for mesh networking.
What components make up the PPDU in 802.11s?
The PPDU consists of a physical layer preamble, header, and MAC frame payload.
How does 802.11s ensure backward compatibility in PPDU?
By using the same PPDU structure as legacy 802.11 PHYs, it maintains compatibility with existing devices.
What is the role of the preamble in the PPDU?
The preamble enables synchronization, channel estimation, and signal detection for the receiver.
Does 802.11s modify MAC headers inside the PPDU?
Yes, 802.11s defines additional mesh control information inside MAC headers but not at the PHY PPDU level.
Are there special mesh measurement frames in the PPDU?
Yes, measurement frames for radio resource management can be transmitted within the PPDU payload.
What PHY modulation schemes are used in 802.11s PPDUs?
Modulation schemes like OFDM and DSSS from underlying PHYs are used unchanged.
How is the data rate decided for PPDUs in 802.11s?
It is dynamically selected based on link quality, channel conditions, and mesh routing metrics.
Can 802.11s PPDUs support multiple bandwidths?
Yes, PPDUs support channel bandwidths inherited from the PHY layer (e.g., 20, 40 MHz).
How does PPDU timing affect mesh performance?
Efficient PPDU timing helps reduce latency and improve throughput in mesh networks.
Are control frames in 802.11s sent inside the PPDU?
Yes, control frames such as acknowledgments and mesh action frames are sent within PPDUs.
What is the maximum size of a PPDU payload in 802.11s?
It follows the maximum PSDU size defined in the base 802.11 standards (usually up to 7935 bytes).
Does 802.11s support aggregation in PPDU?
Yes, frame aggregation techniques like A-MPDU and A-MSDU can be used to improve efficiency.
How are errors handled in 802.11s PPDUs?
Error detection and correction are managed by PHY layer mechanisms such as CRC and FEC.
Can 802.11s mesh nodes decode all PPDUs?
Nodes can decode PPDUs addressed to them or broadcast/multicast frames relevant to mesh operations.
Where can I learn more about 802.11s PPDU structure?
Refer to the IEEE 802.11s standard documentation and PHY layer specifications in base 802.11 standards.
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