How QoS is managed in LTE system | beyond3g
Quality of Service Overview - Technical Documentation - Support - Juniper Networks
- On the radio interface
- Radio bearer control
- Admission control
- Congestion control
- On the transport (backhaul)
- Mapping DSCP with P-bit in VLAN
Quality of Service (QoS) and Policy Management in Mobile Data Networks
3GPP TR 29.839: Home (e)Node B - security gateway interface (Release 11)
QCI | 4G University5.2 H(e)NB procedures5.2.1 GeneralThe H(e)NB shall support DSCP marking on the IPsec header when forwarding the UE uplink traffic.Based on H(e)NB configuration either the QCI mapping or the Reflective QoS may be used.5.2.2 QCI mappingThe QCI mapping table contains a one-to-one mapping from QCI value to DSCP marking value. The QCI mappingtable is configured in the H(e)NB by the operator.
Do we have DSCP marking on the outer IP header (the one above GTP) and how do they look? What specification relate to this topic?how QCI map to the DSCP ??? And DSCP mapping table will be made in router ?? | LinkedIn
Specifications that relate to the S1 interface (also touching the QoS aspects) are TS 36.410, TS 36.411, TS 36.412, TS 36.413 and TS 36.414.
The technical specification TS 36.414 section 5.4 Diffserv code point marking says:
“IP Differentiated Services code point marking  shall be supported. The mapping between traffic categories and Diffserv code points shall be configurable by O&M based on QoS Class Identifier (QCI) Characteristics and others E-UTRAN traffic parameters. Traffic categories are implementation-specific and may be determined from the application parameters”
which means, that there is DSCP marking, but it is defined by a specific implementation.
The SGW, PGW, and eNB all contain QCI to DSCP markings. During bearer setup, the QCI values are communicated from the HSS/PCRF to the PGW, SGW, & eNB. The adjacent routers need only to enforce the DSCP markings set by the EPC elements.
QCI-to-DSCP mapping cannot be fixed by 3GPP standard as it depends on transmission network design. Transmission equipments must prioritze the IP packets according to the service they are carrying, so the mapping must be configured according to TX network.
QCI DSCP Example 3GPP service
1 EF conversational voice
2 EF conversational video
3 EF real-time gaming
4 AF41 buffered streaming
5 AF31 IMS signaling
6 AF31 buffered streaming
7 AF21 interactive gaming
8 AF11 web access
9 BE e-mail
DSCP is field in IP header, QCI is end to end parameter mapped in each part of the network in different parameters or group of parameters (in radio interface, transmission network..). DSCP value mapping to QCI is mapping for prioritizing bearers in transmission network and can be (and will be) done on P-GW, S-GW and eNB: Mapping which you configure on eNB will take place in up-link: when eNodeB has to transmit IP packet which carries GTP packet corresponding to bearer with
CQIQCI 7, eNB will add DSCP value which (according to what you have configured on eNB) corresponds to QCI7 in IP header of that IP package. Important is to emphasize that eNB itself, when receive down-link package, does not care for received DSCP in IP header (placed by S-GW), eNB does not compare recieved DSCP with configured DSCP on eNB for that QCI - moreover, those 2 DSCP values (for UL and DL) can be different, depending of transmission network. What you configure on S-GW for S1 will take place on S1 down-link in the same way as described for eNB... And analogically for other cases...