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diff --git a/net/dcsctp/timer/task_queue_timeout.h b/net/dcsctp/timer/task_queue_timeout.h
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+++ b/net/dcsctp/timer/task_queue_timeout.h
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+/*
+ *  Copyright (c) 2021 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+#ifndef NET_DCSCTP_TIMER_TASK_QUEUE_TIMEOUT_H_
+#define NET_DCSCTP_TIMER_TASK_QUEUE_TIMEOUT_H_
+
+#include <memory>
+#include <utility>
+
+#include "api/task_queue/task_queue_base.h"
+#include "net/dcsctp/public/timeout.h"
+#include "rtc_base/task_utils/pending_task_safety_flag.h"
+
+namespace dcsctp {
+
+// The TaskQueueTimeoutFactory creates `Timeout` instances, which schedules
+// itself to be triggered on the provided `task_queue`, which may be a thread,
+// an actual TaskQueue or something else which supports posting a delayed task.
+//
+// Note that each `DcSctpSocket` must have its own `TaskQueueTimeoutFactory`,
+// as the `TimeoutID` are not unique among sockets.
+//
+// This class must outlive any created Timeout that it has created. Note that
+// the `DcSctpSocket` will ensure that all Timeouts are deleted when the socket
+// is destructed, so this means that this class must outlive the `DcSctpSocket`.
+//
+// This class, and the timeouts created it, are not thread safe.
+class TaskQueueTimeoutFactory {
+ public:
+  // The `get_time` function must return the current time, relative to any
+  // epoch. Whenever a timeout expires, the `on_expired` callback will be
+  // triggered, and then the client should provided `timeout_id` to
+  // `DcSctpSocketInterface::HandleTimeout`.
+  TaskQueueTimeoutFactory(webrtc::TaskQueueBase& task_queue,
+                          std::function<TimeMs()> get_time,
+                          std::function<void(TimeoutID timeout_id)> on_expired)
+      : task_queue_(task_queue),
+        get_time_(std::move(get_time)),
+        on_expired_(std::move(on_expired)) {}
+
+  // Creates an implementation of `Timeout`.
+  std::unique_ptr<Timeout> CreateTimeout() {
+    return std::make_unique<TaskQueueTimeout>(*this);
+  }
+
+ private:
+  class TaskQueueTimeout : public Timeout {
+   public:
+    explicit TaskQueueTimeout(TaskQueueTimeoutFactory& parent);
+    ~TaskQueueTimeout();
+
+    void Start(DurationMs duration_ms, TimeoutID timeout_id) override;
+    void Stop() override;
+
+   private:
+    TaskQueueTimeoutFactory& parent_;
+    // A safety flag to ensure that posted tasks to the task queue don't
+    // reference these object when they go out of scope. Note that this safety
+    // flag will be re-created if the scheduled-but-not-yet-expired task is not
+    // to be run. This happens when there is a posted delayed task with an
+    // expiration time _further away_ than what is now the expected expiration
+    // time. In this scenario, a new delayed task has to be posted with a
+    // shorter duration and the old task has to be forgotten.
+    rtc::scoped_refptr<webrtc::PendingTaskSafetyFlag> pending_task_safety_flag_;
+    // The time when the posted delayed task is set to expire. Will be set to
+    // the infinite future if there is no such task running.
+    TimeMs posted_task_expiration_ = TimeMs::InfiniteFuture();
+    // The time when the timeout expires. It will be set to the infinite future
+    // if the timeout is not running/not started.
+    TimeMs timeout_expiration_ = TimeMs::InfiniteFuture();
+    // The current timeout ID that will be reported when expired.
+    TimeoutID timeout_id_ = TimeoutID(0);
+  };
+
+  RTC_NO_UNIQUE_ADDRESS webrtc::SequenceChecker thread_checker_;
+  webrtc::TaskQueueBase& task_queue_;
+  const std::function<TimeMs()> get_time_;
+  const std::function<void(TimeoutID)> on_expired_;
+};
+}  // namespace dcsctp
+
+#endif  // NET_DCSCTP_TIMER_TASK_QUEUE_TIMEOUT_H_