Radio Measurement service

4.5.8 Radio Measurement service

The Radio Measurement service provides the following:
— The ability to request and report radio measurements in supported channels.
— The ability to perform radio measurements in supported channels.
— An interface for upper layer applications to retrieve radio measurements using MLME primitives
and/or MIB access.
— Information about neighbor APs.
4.5.9 Interworking with external networks
The interworking service allows non-AP STAs to access services provided by an external network according
to the subscription or other characteristics of that external network. An IEEE 802.11 non-AP STA may have
a subscription relationship with an external network, e.g., with an SSPN.
An overview of the interworking functions addressed in this standard is provided below:
— Network discovery and selection
— Discovery of suitable networks through the advertisement of access network type, roaming
consortium and venue information, via management frames
— Selection of a suitable IEEE 802.11 infrastructure using advertisement services (e.g., Access
Network Query Protocol (ANQP) or an IEEE 802.21 Information Server) in the BSS or in an
external network reachable via the BSS.
— Selection of an SSPN or external network with its corresponding IEEE 802.11 infrastructure
— Emergency services
— Emergency Call and Network Alert support at the link level
— QoS Map distribution
— SSPN interface service between the AP and the SSPN
The generic advertisement service (GAS), described in 4.11, provides both support for a STA’s network
selection and a conduit for communication by a non-AP STA with other information resources in a network
before joining the wireless LAN.
The interworking service supports emergency services by providing methods for users to access emergency
services via the IEEE 802.11 infrastructure, advertising that emergency services are supported (see 10.24.6)
and identifying that a traffic stream is used for emergency services.

The interworking service provides QoS mapping for SSPNs and other external networks. Since each SSPN
or other external network may have its own layer-3 end-to-end packet marking practice (e.g., differentiated
services code point (DSCP) usage conventions), a means to remap the layer-3 service levels to a common
over-the-air service level is necessary. The QoS Map service provides STAs a mapping of network-layer
QoS packet marking to over-the-air QoS frame marking (i.e., user priority).
The SSPN Interface service supports service provisioning and transfer of user permissions from the SSPN to
the AP. The method and protocol by which these permissions are transferred from the SSPN are outside the
scope of this standard.