diff --git a/ndn-cpp/node.cpp b/ndn-cpp/node.cpp
index b8773fc..8a46384 100644
--- a/ndn-cpp/node.cpp
+++ b/ndn-cpp/node.cpp
@@ -97,7 +97,7 @@
   }
 }
 
-void Node::onReceivedElement(unsigned char *element, unsigned int elementLength)
+void Node::onReceivedElement(const unsigned char *element, unsigned int elementLength)
 {
   BinaryXmlDecoder decoder(element, elementLength);