diff --git a/include/ndn-cpp/encoding/oid.hpp b/include/ndn-cpp/encoding/oid.hpp
index f217889..f89339c 100644
--- a/include/ndn-cpp/encoding/oid.hpp
+++ b/include/ndn-cpp/encoding/oid.hpp
@@ -12,6 +12,8 @@
 #include <vector>
 #include <string>
 
+namespace CryptoPP { class BufferedTransformation; }
+
 namespace ndn {
 
 class OID {
@@ -50,6 +52,12 @@
   {
     return !equal(oid);
   }
+
+  void
+  encode(CryptoPP::BufferedTransformation &out) const;
+
+  void
+  decode(CryptoPP::BufferedTransformation &in);
   
 private:
   bool equal(const OID& oid) const;