1 files changed, 79 insertions, 0 deletions
diff --git a/libtransport/src/protocols/rtc/rtc_rc_frame.cc b/libtransport/src/protocols/rtc/rtc_rc_frame.cc
new file mode 100644
index 000000000..b577b5bea
--- /dev/null
+++ b/libtransport/src/protocols/rtc/rtc_rc_frame.cc
@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2017-2021 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.
+ */
+
+#include <protocols/rtc/rtc_consts.h>
+#include <protocols/rtc/rtc_rc_frame.h>
+
+#include <algorithm>
+
+namespace transport {
+
+namespace protocol {
+
+namespace rtc {
+
+RTCRateControlFrame::RTCRateControlFrame() : cc_detector_() {}
+
+RTCRateControlFrame::~RTCRateControlFrame() {}
+
+void RTCRateControlFrame::onNewRound(double round_len) {
+  if (!rc_on_) return;
+
+  CongestionState prev_congestion_state = congestion_state_;
+  cc_detector_.updateStats();
+  congestion_state_ = (CongestionState)cc_detector_.getState();
+
+  if (congestion_state_ == CongestionState::Congested) {
+    if (prev_congestion_state == CongestionState::Normal) {
+      // congestion detected, notify app and init congestion win
+      double prod_rate = protocol_state_->getReceivedRate();
+      double rtt = (double)protocol_state_->getRTT() / MILLI_IN_A_SEC;
+      double packet_size = protocol_state_->getAveragePacketSize();
+
+      if (prod_rate == 0.0 || rtt == 0.0 || packet_size == 0.0) {
+        // TODO do something
+        return;
+      }
+
+      congestion_win_ = (uint32_t)ceil(prod_rate * rtt / packet_size);
+    }
+    uint32_t win = congestion_win_ * WIN_DECREASE_FACTOR;
+    congestion_win_ = std::max(win, WIN_MIN);
+    return;
+  }
+}
+
+void RTCRateControlFrame::onDataPacketReceived(
+    const core::ContentObject &content_object) {
+  if (!rc_on_) return;
+
+  uint32_t seq = content_object.getName().getSuffix();
+  if (!protocol_state_->isPending(seq)) return;
+
+  cc_detector_.addPacket(content_object);
+}
+
+void RTCRateControlFrame::receivedBwProbeTrain(uint64_t firts_probe_ts,
+                                               uint64_t last_probe_ts,
+                                               uint32_t total_probes) {
+  // TODO
+  return;
+}
+
+}  // end namespace rtc
+
+}  // end namespace protocol
+
+}  // end namespace transport