Added a virtual destructor.
diff --git a/ndn-cpp/transport/transport.cpp b/ndn-cpp/transport/transport.cpp
index f15e2ea..e16a879 100644
--- a/ndn-cpp/transport/transport.cpp
+++ b/ndn-cpp/transport/transport.cpp
@@ -29,4 +29,8 @@
 {
 }
 
+Transport::~Transport()
+{
+}
+
 }