diff --git a/scheduler/interval-generator.h b/scheduler/interval-generator.h
new file mode 100644
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--- /dev/null
+++ b/scheduler/interval-generator.h
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+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2013 University of California, Los Angeles
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: Zhenkai Zhu <zhenkai@cs.ucla.edu>
+ *         Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ */
+
+#ifndef INTERVAL_GENERATOR_H
+#define INTERVAL_GENERATOR_H
+
+#include <boost/shared_ptr.hpp>
+
+using namespace std;
+
+class IntervalGenerator;
+typedef boost::shared_ptr<IntervalGenerator> IntervalGeneratorPtr;
+
+class IntervalGenerator
+{
+public:
+  virtual double
+  nextInterval() = 0;
+};
+
+
+#endif // INTERVAL_GENERATOR_H