docs: Update documentation and Doxygen documentation generation
diff --git a/utils/ndn-rtt-estimator.h b/utils/ndn-rtt-estimator.h
index 287452e..8da703b 100644
--- a/utils/ndn-rtt-estimator.h
+++ b/utils/ndn-rtt-estimator.h
@@ -36,7 +36,7 @@
 namespace ndn {
 
 /**
- * \ingroup tcp
+ * \ingroup ndn-apps
  *
  * \brief Helper class to store RTT measurements
  */