E.34 Bi-directional speech (EVS 24.4, IPv6, RTCP and MBR=GBR bearer)

26.1143GPPIP Multimedia Subsystem (IMS)Media handling and interactionMultimedia telephonyRelease 18TS

The bit-rate for EVS 24.4 including IP overhead (one EVS frame per RTP packet, using Header-Full format) is 49.2 kbps which is rounded up to 50 kbps. IPv6 is assumed.

Table E.35: QoS mapping for bi-directional speech (EVS 24.4, IPv6, RTCP and MBR=GBR bearer)

Traffic class

Conversational class

Notes

Delivery order

No

The application should handle packet reordering.

Maximum SDU size (octets)

1400

Maximum size of IP packets.

Delivery of erroneous SDUs

No

Residual BER

[10-5]

Reflects the desire to have a medium level of protection to achieve an acceptable compromise between packet loss rate and speech transport delay and delay variation.

SDU error ratio

[7*10-3]

A packet loss rate of 0.7 % per wireless link is in general sufficient for speech services.

Transfer delay (ms)

130 ms

Indicates maximum delay for 95th percentile of the distribution of delay for all delivered SDUs between the UE and the PS domain during the lifetime of a bearer service. Permits the derivation of the RAN part of the total transfer delay for the radio access bearer. This attribute allows RAN to set transport formats and H-ARQ/ARQ parameters such as the discard timer.

Guaranteed bit-rate for uplink (kbps)

52

The total bit-rate of EVS 24.4 including IP/UDP/RTP overhead and 2000 bps for RTCP.

Maximum bit-rate for uplink (kbps)

52

The same as the guaranteed bit-rate.

Guaranteed bit-rate for downlink (kbps)

52

The total bit-rate of EVS 24.4 including IP/UDP/RTP overhead and 2000 bps for RTCP.

Maximum bit-rate for downlink (kbps)

52

The same as the guaranteed bit-rate.

Allocation/Retention priority

subscribed value

Indicates the relative importance to other radio access bearers. It should be the next lower value to the priority of the signalling bearer.

Source statistics descriptor

‘speech’

NOTE: Residual BER and SDU error ratio of EVS are for further study.

Annex F (Normative):
Void

Annex G (Normative):
DTMF events