802.11u MAC Functions
What are the primary MAC functions enhanced by IEEE 802.11u?
802.11u extends MAC functions to support network discovery, pre-association queries, and interworking with external networks.
How does 802.11u handle MAC layer network selection?
It enables MAC to process ANQP responses before association to choose the most appropriate network.
Does 802.11u modify frame formats at the MAC layer?
Yes, it introduces new Information Elements (IEs) in management frames to carry additional interworking and network info.
What role does the MAC layer play in GAS (Generic Advertisement Service)?
The MAC layer provides the transport mechanism for GAS frames, allowing ANQP queries and responses between clients and APs.
How does 802.11u improve MAC layer authentication?
It supports more dynamic and seamless authentication methods facilitating roaming and interworking at the MAC level.
Are there any MAC timing changes in 802.11u?
While MAC timing principles remain, 802.11u may affect timing by adding pre-association query exchanges via GAS.
Does 802.11u affect power saving features at the MAC layer?
Indirectly, yes—by optimizing network selection and reducing scanning times, it can help conserve device battery life.
How does 802.11u support interworking with cellular networks at the MAC level?
It allows MAC management frames to carry interworking information elements that aid seamless roaming between Wi-Fi and cellular.
What new management frames or elements are introduced by 802.11u in MAC?
802.11u introduces elements like Access Network Type, Roaming Consortium, Venue Info, and Emergency Alert within MAC management frames.
Does 802.11u support backward compatibility at the MAC layer?
Yes, it ensures legacy devices can still associate normally while enabling enhanced functions for 802.11u-capable devices.
How does 802.11u MAC layer support faster network handoffs?
By pre-fetching network information and supporting seamless authentication processes at the MAC level.
Are fragmentation or retransmission mechanisms altered in 802.11u MAC?
No, core MAC reliability mechanisms like fragmentation and retransmission remain unchanged.
How does 802.11u assist in emergency services at the MAC layer?
It enables MAC frames to advertise emergency services availability, helping devices identify suitable networks quickly.
What is the role of MAC in managing network access for guest users in 802.11u?
MAC functions help support guest network identification and appropriate access control using new interworking elements.
Does 802.11u MAC layer support QoS enhancements?
It complements existing QoS by enabling network selection based on service capabilities, indirectly supporting QoS improvements.
How is MAC security impacted by 802.11u?
802.11u facilitates stronger authentication and network selection security through enhanced info elements and protocols.
Are there any new MAC timers or counters introduced by 802.11u?
No new timers or counters are specifically introduced, but additional frame exchanges may affect overall timing.
How does 802.11u MAC layer affect multi-SSID or virtual AP operation?
It supports broadcasting interworking info on multiple SSIDs, enhancing user choice across virtual networks.
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