Based on the 3GPP EVS Selection and Characterization results that included AMR-WB, AMR-WB with G718IO, and EVS codec, this clause provides an example set of Max. PLR operating points that the terminal may indicate to the PCRF/PCF.
The following examples illustrate the use of the SDP attributes and parameters specified for the CHEM feature.
The example in
Table X.2.2-1 demonstrates how, as specified in
clause W.2, the receiver in the offering MTSI client supports and offers to request adaptation to different codec configurations to provide different levels of packet loss robustness without using application layer redundancy.
SDP offer |
m=audio 49152 RTP/AVP 97 98 99 100 101 105 106
b=AS:50
b=RS:0
b=RR:2500
a=rtpmap:97 EVS/16000/1
a=fmtp:97 br=5.9-24.4; bw=nb-swb; max-red=200
a=rtpmap:98 AMR-WB/16000/1
a=fmtp:98 mode-change-capability=2; max-red=200
a=rtpmap:99 AMR-WB/16000/1
a=fmtp:99 mode-change-capability=2; max-red=200; octet-align=1
a=rtpmap:100 AMR/8000/1
a=fmtp:100 mode-change-capability=2; max-red=200
a=rtpmap:101 AMR/8000/1
a=fmtp:101 mode-change-capability=2; max-red=200; octet-align=1
a=rtpmap:105 telephone-event/16000
a=fmtp:105 0-15
a=rtpmap:106 telephone-event/8000
a=fmtp:106 0-15
a=ptime:20
a=maxptime:240
a=PLR_adapt
|
The example in
Table X.2.2-2 is one possible response to the offer in
Table X.2.2-1 and demonstrates how, as specified in
clause W.2, the receiver in the answering MTSI client also supports and negotiates requesting adaptation to different codec configurations to provide different levels of packet loss robustness without using application layer redundancy. During the ensuing session both the offerer MTSI client and answerer MTSI client request robustness adaptation without application layer redundancy. The PCRF/PCFs should choose to use more robust handover thresholds that do not rely on application layer redundancy in both the uplink and downlink directions.
SDP answer |
m=audio 49152 RTP/AVP 97 105
b=AS:50
b=RS:0
b=RR:2500
a=rtpmap:97 EVS/16000/1
a=fmtp:97 br=5.9-24.4; bw=nb-swb; max-red=200
a=rtpmap:105 telephone-event/16000
a=fmtp:105 0-15
a=ptime:20
a=maxptime:240
a=PLR_adapt
|
The example in
Table X.2.2-3 is another possible response to the offer in
Table X.2.2-1 and demonstrates how, as specified in
clause W.2, the receiver in the answering MTSI client does not support requesting adaptation to different codec configurations to provide different levels of packet loss robustness. In the ensuing session, media robustness adaptation is not enabled in either direction of media transmission so the PCRF/PCFs should not use more robust handover thresholds in either the uplink or downlink direction.
SDP answer |
m=audio 49152 RTP/AVP 97 105
b=AS:50
b=RS:0
b=RR:2500
a=rtpmap:97 EVS/16000/1
a=fmtp:97 br=5.9-24.4; bw=nb-swb; max-red=200
a=rtpmap:105 telephone-event/16000
a=fmtp:105 0-15
a=ptime:20
a=maxptime:240
|
The example in
Table X.2.3-1 demonstrates how, as specified in
clause W.3, the receiver in the offering MTSI client supports and offers to request adaptation to different codec configurations to provide different levels of packet loss robustness using application layer redundancy.
SDP offer |
m=audio 49152 RTP/AVP 97 98 99 100 101 105 106
b=AS:50
b=RS:0
b=RR:2500
a=rtpmap:97 EVS/16000/1
a=fmtp:97 br=5.9-24.4; bw=nb-swb; max-red=200
a=rtpmap:98 AMR-WB/16000/1
a=fmtp:98 mode-change-capability=2; max-red=200
a=rtpmap:99 AMR-WB/16000/1
a=fmtp:99 mode-change-capability=2; max-red=200; octet-align=1
a=rtpmap:100 AMR/8000/1
a=fmtp:100 mode-change-capability=2; max-red=200
a=rtpmap:101 AMR/8000/1
a=fmtp:101 mode-change-capability=2; max-red=200; octet-align=1
a=rtpmap:105 telephone-event/16000
a=fmtp:105 0-15
a=rtpmap:106 telephone-event/8000
a=fmtp:106 0-15
a=ptime:20
a=maxptime:240
a=PLR_adapt:ALR
|
The example in
Table X.2.3-2 is one possible response to the offer in
Table X.2.3-1 and demonstrates how, as specified in
clause W.3, the receiver in the answering MTSI client also supports and negotiates requesting adaptation to different codec configurations to provide different levels of packet loss robustness using application layer redundancy. During the ensuing session both the offerer MTSI client and answerer MTSI client request robustness adaptation and can use the in-band RTP CMR codepoints specified in
clause W.3 to request application layer redundancy. The PCRF/PCFs should choose to use more robust handover thresholds (both using application layer redundancy or not) in both the uplink and downlink directions.
SDP answer |
m=audio 49152 RTP/AVP 97 105
b=AS:50
b=RS:0
b=RR:2500
a=rtpmap:97 EVS/16000/1
a=fmtp:97 br=5.9-24.4; bw=nb-swb; max-red=200
a=rtpmap:105 telephone-event/16000
a=fmtp:105 0-15
a=ptime:20
a=maxptime:240
a=PLR_adapt:ALR
|
The example in
Table X.2.3-3 is another possible response to the offer in
Table X.2.3-1 and demonstrates how, as specified in
clause W.2 and
clause W.3, the receiver in the answering MTSI client supports requesting adaptation to different codec configurations but not using application layer redundancy. During the ensuing session both the offerer MTSI client and answerer MTSI client request robustness adaptation without application layer redundancy. The PCRF/PCFs should choose to use more robust handover thresholds that do not rely on application layer redundancy in both the uplink and downlink directions.
SDP answer |
m=audio 49152 RTP/AVP 97 105
b=AS:50
b=RS:0
b=RR:2500
a=rtpmap:97 EVS/16000/1
a=fmtp:97 br=5.9-24.4; bw=nb-swb; max-red=200
a=rtpmap:105 telephone-event/16000
a=fmtp:105 0-15
a=ptime:20
a=maxptime:240
a=PLR_adapt
|
The example in
Table X.2.4-1 demonstrates how, as specified in
clause W.4.2, the media receiver in the offering MTSI terminal receiver can handle up to 3.50% end-to-end PLR for the EVS codec, proposes to use 1.50% PLR on its downlink and 2.00% for its uplink, and can handle up to 2.00% end-to-end PLR for the AMR-WB codec, proposes to use 0.75% PLR on its downlink and 1.25% for its uplink. The example does not use application layer redundancy but could easily apply to sessions using application layer redundancy by including the ALR parameter in the PLR_adapt attribute as specified in
clause W.3.
SDP offer |
m=audio 49152 RTP/AVP 97 98 99 100 101 105 106
b=AS:50
b=RS:0
b=RR:2500
a=rtpmap:97 EVS/16000/1
a=fmtp:97 br=5.9-24.4; bw=nb-swb; max-red=200
a=rtpmap:98 AMR-WB/16000/1
a=fmtp:98 mode-change-capability=2; max-red=200
a=rtpmap:99 AMR-WB/16000/1
a=fmtp:99 mode-change-capability=2; max-red=200; octet-align=1
a=rtpmap:100 AMR/8000/1
a=fmtp:100 mode-change-capability=2; max-red=200
a=rtpmap:101 AMR/8000/1
a=fmtp:101 mode-change-capability=2; max-red=200; octet-align=1
a=rtpmap:105 telephone-event/16000
a=fmtp:105 0-15
a=rtpmap:106 telephone-event/8000
a=fmtp:106 0-15
a=ptime:20
a=maxptime:240
a=PLR_adapt
a=MAXimum-e2e-PLR:97 350:150/200
a=MAXimum-e2e-PLR:98 200:75/125
a=MAXimum-e2e-PLR:99 200:75/125
|
The example in
Table X.2.4-2 is one possible response to the offer in
Table X.2.4-1 and demonstrates how, as specified in
clause W.4.3, the receiver in the answering MTSI terminal supports up to 4.00% end-to-end PLR for the EVS codec, proposes to use 2.00% PLR on both its downlink and uplink. This leaves 1.50% for the downlink and 2.00% for the uplink to the offerering MTSI terminal which matches what was proposed in the SDP offer.
SDP answer |
m=audio 49152 RTP/AVP 97 105
b=AS:50
b=RS:0
b=RR:2500
a=rtpmap:97 EVS/16000/1
a=fmtp:97 br=5.9-24.4; bw=nb-swb; max-red=200
a=rtpmap:105 telephone-event/16000
a=fmtp:105 0-15
a=ptime:20
a=maxptime:240
a=PLR_adapt
a=MAXimum-e2e-PLR:97 400:200/200
|
The example in
Table X.2.4-3 is another possible response to the offer in
Table X.2.4-1 and demonstrates how, as specified in
clause W.4.3, the receiver in the answering MTSI terminal supports up to 3.50% end-to-end PLR for the EVS codec, proposes to use 1.75% PLR on both its downlink and uplink. This leaves 1.75% for each of the uplink and downlink to the offerering MTSI terminal which is higher than the downlink PLR (i.e., the answerer is being more generous to the offerer) and lower than the uplink PLR (i.e., the answerer not agreeing to let the offerer be greedy) proposed in the SDP offer.
SDP answer |
m=audio 49152 RTP/AVP 97 105
b=AS:50
b=RS:0
b=RR:2500
a=rtpmap:97 EVS/16000/1
a=fmtp:97 br=5.9-24.4; bw=nb-swb; max-red=200
a=rtpmap:105 telephone-event/16000
a=fmtp:105 0-15
a=ptime:20
a=maxptime:240
a=PLR_adapt
a=MAXimum-e2e-PLR:97 350:175/175
|