5G Quality of Service(QoS)

5G promises a range of capabilities from downloading a movie fast(example: under 5 seconds) to supporting real-time low-latency of Industrial IoT(Internet of Things), factory automation or self-driving cars. This range of capabilities requires that the Quality of Service (QoS) characteristics, such as delay, error rate, and priority be specified and enforced. 5G enhances the QoS options compared to 4G LTE.

The concept of QoS in 5G is flow based. Packets are classified and marked using QFI (QoS Flow Identifier). The 5G QoS flows are mapped in the AN (Access Network) to DRBs (Data Radio Bearers) unlike 4G LTE where mapping is one to one between EPC and radio bearers. It supports following QoS flow types. 

QoS flow is identified by QFI within PDU session. This QFI is carried in an encapsulation header over NG-U. For each UE, 5GC establishes one or more PDU sessions and NG-RAN establishes at least one DRB together with PDU session. Additional DRBs are configured for QoS flows of that PDU session consecutively.
 
• GBR(Guaranteed Bit Rate) QoS flow, requires guaranteed flow bit rate   
• Non-GBR QoS flow, does not require guaranteed flow bit rate    

Following are the benefits or advantages of 5G QoS in NR =>

• It delivers critical communication services for mission critical users/organizations.   
• It provides different prioritization levels for different applications as per users preset requirements with the operators.   
• It provides help to people during disasters and emergency situations such as floods, earthquake etc.
• The service is always available for emergency callers

ref:

Quality of Service (QoS) for 5G Networks -   

• http://www.ijfcc.org/vol6/483-GS0004.pdf
• https://www.awardsolutions.com/portal/shareables/what-is-5G/5G-Training-Online/quality-service-model-5g-prasad-govindarajan

5G NR QoS - http://www.rfwireless-world.com/5G/5G-NR-QoS.html

5G NR User Plane Protocol - http://www.techplayon.com/5g-nr-radio-protocol-user-plane-whats-new-lte-5g-nr/ 

Quality of Service (QoS) concept and architecture (Specification #: 23.107) -

• https://www.etsi.org/deliver/etsi_ts/123100_123199/123107/10.01.00_60/ts_123107v100100p.pdf
• https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=783

AT command set for User Equipment (UE): Specification #: 27.007 -

• https://www.etsi.org/deliver/etsi_ts/127000_127099/127007/10.03.00_60/ts_127007v100300p.pdf
• https://portal.3gpp.org/desktopmodules/Specification/SpecificationDetails.aspx?specificationId=1515

5G Session Management Spec - https://www.etsi.org/deliver/etsi_ts/129500_129599/129512/15.00.00_60/ts_129512v150000p.pdf

Enabling ICN in 3GPP's 5G NextGen Core Architecture  - https://tools.ietf.org/id/draft-ravi-icnrg-5gc-icn-03.html

Misc - 
https://www.researchgate.net/figure/5G-NG-RAN-Protocol-Stack-and-5G-QoS-Architecture_fig6_323184543