1 files changed, 69 insertions, 0 deletions
diff --git a/libtransport/includes/hicn/transport/utils/rtc_quality_score.h b/libtransport/includes/hicn/transport/utils/rtc_quality_score.h
new file mode 100644
index 000000000..2e8ca97d3
--- /dev/null
+++ b/libtransport/includes/hicn/transport/utils/rtc_quality_score.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2021 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+namespace transport {
+
+namespace protocol {
+
+namespace rtc {
+
+class RTCQualityScore {
+ public:
+  RTCQualityScore(){};
+  ~RTCQualityScore(){};
+
+  uint8_t getQualityScore(uint64_t RTT, uint32_t loss_rate) {
+    uint32_t delay_index = getDelay(RTT);
+    uint32_t loss_index = getLossRate(loss_rate);
+    return quality_score_[loss_index][delay_index];
+  }
+
+ private:
+  // see quality score map
+  uint8_t quality_score_[7][6]{{5, 5, 5, 4, 3, 1}, {5, 4, 3, 2, 1, 1},
+                               {5, 3, 2, 1, 1, 1}, {5, 2, 1, 1, 1, 1},
+                               {4, 1, 1, 1, 1, 1}, {3, 1, 1, 1, 1, 1},
+                               {1, 1, 1, 1, 1, 1}};
+
+  uint8_t getDelay(uint64_t RTT) {
+    uint64_t OWD = RTT / 2;
+    // we should never get a OWD of 0. so we take the first col if OWD is < 5ms
+    if (OWD < 5) return 0;
+    if (OWD < 50) return 1;
+    if (OWD < 100) return 2;
+    if (OWD < 200) return 3;
+    if (OWD < 300) return 4;
+    return 5;
+  }
+
+  uint8_t getLossRate(uint32_t loss_rate) {
+    // we use 3% as mean loss rate
+    if (loss_rate < 3) return 0;
+    if (loss_rate < 10) return 1;
+    if (loss_rate < 20) return 2;
+    if (loss_rate < 30) return 3;
+    if (loss_rate < 40) return 4;
+    if (loss_rate < 50) return 5;
+    return 6;
+  }
+};
+
+}  // namespace rtc
+
+}  // namespace protocol
+
+}  // namespace transport