802.11w PHYs
What is 802.11w PHY?
802.11w does not define a new PHY; it operates on existing PHY layers of 802.11 standards, adding management frame protection.
Does 802.11w affect modulation or coding schemes?
No, 802.11w operates independently of modulation and coding schemes, which are defined by the underlying PHY (e.g., 802.11a, 802.11n).
How does 802.11w improve PHY layer security?
It protects management frames by encrypting them, preventing spoofing and spoofed disassociation attacks that can disrupt PHY communication.
Which frequency bands does 802.11w work on?
802.11w works on all frequency bands supported by the underlying PHY, including 2.4 GHz and 5 GHz bands.
Does 802.11w require changes to OFDM or DSSS PHY?
No, 802.11w adds security features at higher layers without altering PHY modulation techniques like OFDM or DSSS.
Can 802.11w cause PHY layer overhead?
Slightly, due to additional encryption and authentication of management frames, but PHY data rates remain unchanged.
Is 802.11w compatible with half-duplex PHY like 802.11a?
Yes, 802.11w works transparently over half-duplex or full-duplex PHY implementations.
Does 802.11w support MIMO or spatial streams?
802.11w is PHY-agnostic and thus supports underlying PHY features like MIMO in 802.11n/ac without modifications.
How does 802.11w affect latency at the PHY?
The added encryption processing may introduce minimal latency, but PHY symbol timing and transmission remain unaffected.
Does 802.11w impact spectral efficiency?
No direct impact on spectral efficiency since it secures management frames, which are a small portion of overall transmissions.
How does 802.11w interact with PHY preamble and header?
802.11w frames use the standard PHY preamble and header defined by the underlying PHY standard without changes.
Is 802.11w backward compatible with older PHYs?
Yes, but management frame protection features may be limited or disabled if the peer device does not support 802.11w.
Can 802.11w operate over 20 MHz and 40 MHz channels?
Yes, it is independent of channel width and functions over any channel supported by the PHY.
Does 802.11w change channel selection or frequency use?
No, channel planning and frequency use remain governed by the PHY and regulatory rules, unaffected by 802.11w.
What PHY layers are commonly used with 802.11w?
802.11a, 802.11b/g, 802.11n, and newer PHY layers commonly incorporate 802.11w for enhanced security.
Does 802.11w require hardware changes in PHY?
Typically no, 802.11w is implemented mostly in firmware and software layers above the PHY.
How does 802.11w improve reliability of PHY communication?
By securing management frames, it reduces denial-of-service attacks that can disrupt PHY connectivity.
Is 802.11w mandatory in modern Wi-Fi standards?
Yes, management frame protection is required or strongly recommended in modern standards like 802.11ac and 802.11ax.
Does 802.11w affect PHY transmit power?
No, transmit power settings are managed by PHY and regulatory constraints, unaffected by 802.11w.
Can 802.11w protect management frames in noisy PHY environments?
Yes, encryption and integrity checks enhance protection even when the PHY experiences interference or errors.
Summary: How does 802.11w relate to PHY?
802.11w complements the PHY by securing management frames at higher layers, working transparently with all PHY types without altering physical transmission characteristics.
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