change to consumberCbr.h
diff --git a/apps/ndn-consumer-cbr.h b/apps/ndn-consumer-cbr.h
index 26fef1d..8ab4472 100644
--- a/apps/ndn-consumer-cbr.h
+++ b/apps/ndn-consumer-cbr.h
@@ -89,6 +89,7 @@
   // GetDesiredRate () const;
   
 private:
+protected:
   double              m_frequency; // Frequency of interest packets (in hertz)
   bool                m_firstTime;
   RandomVariable      *m_random;