List of PPDUs Supported in 802.11u
What is a PPDU in IEEE 802.11u?
PPDU stands for Physical Protocol Data Unit, which is the format of the data sent over the wireless medium at the physical layer.
Does 802.11u define a new PPDU format?
No, 802.11u builds upon existing 802.11 PHY layers and uses the PPDU formats defined in base standards like 802.11a/g/n/ac.
How is PPDU related to MAC frames in 802.11u?
The MAC frames are encapsulated inside the PPDU payload for transmission over the physical medium.
What components make up a PPDU?
Typical components include the preamble, header (SIGNAL field), and payload (data).
What is the purpose of the preamble in a PPDU?
The preamble is used for synchronization, channel estimation, and signaling between sender and receiver.
Does 802.11u impact modulation or coding schemes in the PPDU?
No, modulation and coding are defined by the underlying PHY standard, not directly modified by 802.11u.
How does 802.11u affect PPDU transmission timing?
802.11u does not alter timing parameters; it focuses on network interworking at higher layers.
Are there specific PPDU types used in 802.11u?
No new PPDU types; standard data, management, and control PPDU types are used.
Does 802.11u specify any additional fields within the PPDU?
No additional physical layer fields; enhancements occur at MAC and higher layers.
Can 802.11u affect PPDU size?
Indirectly, network selection and roaming behaviors may affect packet sizes, but PPDU format remains consistent.
How does 802.11u improve reliability at the PPDU level?
Reliability is managed by underlying PHY and MAC mechanisms; 802.11u supports seamless network transitions to maintain connection quality.
Does 802.11u support multi-band PPDU transmissions?
802.11u supports network selection across bands but relies on PHY layers for actual PPDU transmissions.
Is PPDU encryption affected by 802.11u?
Encryption is handled by security protocols like WPA2/3 at higher layers, not by 802.11u at the PPDU level.
What role does the SIGNAL field in the PPDU play?
It communicates data rate and length information needed for decoding the payload.
Does 802.11u introduce changes in PPDU error detection?
No, error detection is handled by CRC at the PHY and MAC layers unchanged by 802.11u.
How does PPDU relate to 802.11u’s interworking functions?
PPDU serves as the physical transmission unit, carrying frames that contain interworking info defined by 802.11u.
Are there specific PPDU requirements for 802.11u network discovery?
No, discovery uses standard beacon and probe frames transmitted via conventional PPDUs.
Can 802.11u facilitate PPDU aggregation or fragmentation?
Aggregation/fragmentation occurs at MAC layer; 802.11u does not modify PPDU structure for these purposes.
Where can I learn more about PPDU formats used with 802.11u?
Consult the base 802.11 standards (a/g/n/ac) for PHY details since 802.11u builds on these without modifying PPDU structure.
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