Local and Dynamic Quality Priority and Pre-emption

Summary

The management of radio and network infrastructure resources in a nationwide interoperable network is critical in maintaining effective operations during periods of congestion, particularly when there are large incidents involving many public safety users in a small area. Quality of Service (QoS), Priority, and Pre-emption (QPP) capabilities will provide FirstNet with the ability to efficiently manage Long Term Evolution (LTE) radio and network resources. The Public Safety Communications Research (PSCR) program is researching the technical methods and capabilities that can enable a public safety nationwide network with dynamic and local control QPP capabilities. This will ensure that priority public safety users gain and maintain access to critical FirstNet resources when demand exceeds capacity.

Description

Higher priority users Pre-empting lower priority users with QPP policy in a congested LTE cell

The Middle Class Tax Relief and Job Creation Act of 2012 (H.R. 3630) appropriated $7 billion for the establishment of a nationwide interoperable public safety broadband network under FirstNet, an independent authority in the National Telecommunications and Information Administration (NTIA). FirstNet will provide first responders with dedicated and prioritized access to high-speed data, voice, and other mission critical applications. This nationwide network will enable public safety agencies at the federal, state, and local levels to effectively conduct their mission by establishing a common communications system based on 3GPP LTE standards. PSCR, a joint program between The National Institute for Standards and Technology (NIST) and NTIA, is sponsored by FirstNet to identify, test, and measure dynamic mechanisms in the LTE core and radio networks that resources based on access and priority policies. FirstNet is also sponsoring research of QPP performance in a local control environment, which allows user changes of access and priority policies. In a separate PSCR project, the U.S. Department of Homeland Security sponsors the technical mechanisms and implementation/operation of local control.

AN INNOVATIVE APPROACH

PSCR has extensive expertise in QPP, primarily through its sponsored work in FY2015 for FirstNet.  PSCR is also leverages cooperative research and development agreements (CRADAs) with industry partners who provide vendor products and support.  
During FY2015 research, PSCR developed testing, measurement, and analysis methods/capabilities for determining the effectiveness of QPP mechanisms in a real LTE system.  In FY2016, Local and Dynamic QPP research will build upon PSCR’s existing expertise and capability set with the following approach:
•    Identify industry support of dynamic control trigger and management mechanisms inside the LTE system
•    Measure the effect of dynamic control mechanisms on network congestion and their effect on user/network performance
•    Collaborate with PSCR Local Control project team to enable local control QPP tests
•    Define common QPP performance metrics that measure network loading, QPP management effectiveness, and resulting user experience

VALUE TO PUBLIC SAFETY

FirstNet’s ability to manage network resources is critical in establishing an LTE network that provides priority public safety users with the tools they need to accomplish their mission.  This research will result in FirstNet operators properly implementing and leveraging QPP capabilities, which will enable maximized network and priority user performance in critical incidents as well as daily operation.

Traffic scheduling prioritization for higher priority users

Automatic access class barring limiting access to radio network for lower priority users