diff --git a/ndn-cpp/encoding/binary-xml-decoder.hpp b/ndn-cpp/encoding/binary-xml-decoder.hpp
index 1bbca34..f75d4f0 100644
--- a/ndn-cpp/encoding/binary-xml-decoder.hpp
+++ b/ndn-cpp/encoding/binary-xml-decoder.hpp
@@ -22,7 +22,7 @@
   /**
    * Initialize the base ndn_BinaryXmlDecoder struct with the input.
    */
-  BinaryXmlDecoder(const uint8_t *input, unsigned int inputLength) 
+  BinaryXmlDecoder(const uint8_t *input, size_t inputLength) 
   {
     ndn_BinaryXmlDecoder_initialize(this, (uint8_t *)input, inputLength);
   }
diff --git a/ndn-cpp/encoding/binary-xml-element-reader.cpp b/ndn-cpp/encoding/binary-xml-element-reader.cpp
index bfb9a2a..559af7f 100644
--- a/ndn-cpp/encoding/binary-xml-element-reader.cpp
+++ b/ndn-cpp/encoding/binary-xml-element-reader.cpp
@@ -9,7 +9,7 @@
 namespace ndn {
 
 void 
-ElementListener::staticOnReceivedElement(struct ndn_ElementListener *self, uint8_t *element, unsigned int elementLength)
+ElementListener::staticOnReceivedElement(struct ndn_ElementListener *self, uint8_t *element, size_t elementLength)
 {
   ((ElementListener *)self)->onReceivedElement(element, elementLength);
 }
diff --git a/ndn-cpp/encoding/binary-xml-element-reader.hpp b/ndn-cpp/encoding/binary-xml-element-reader.hpp
index 5aed8a0..f353e97 100644
--- a/ndn-cpp/encoding/binary-xml-element-reader.hpp
+++ b/ndn-cpp/encoding/binary-xml-element-reader.hpp
@@ -29,7 +29,7 @@
    * @param elementLength length of element
    */
   virtual void 
-  onReceivedElement(const uint8_t *element, unsigned int elementLength) = 0;
+  onReceivedElement(const uint8_t *element, size_t elementLength) = 0;
   
 private:
   /**
@@ -39,7 +39,7 @@
    * @param elementLength
    */
   static void 
-  staticOnReceivedElement(struct ndn_ElementListener *self, uint8_t *element, unsigned int elementLength);
+  staticOnReceivedElement(struct ndn_ElementListener *self, uint8_t *element, size_t elementLength);
 };
 
 }
diff --git a/ndn-cpp/encoding/binary-xml-structure-decoder.hpp b/ndn-cpp/encoding/binary-xml-structure-decoder.hpp
index 0fbc1cf..e953a1b 100644
--- a/ndn-cpp/encoding/binary-xml-structure-decoder.hpp
+++ b/ndn-cpp/encoding/binary-xml-structure-decoder.hpp
@@ -31,7 +31,7 @@
    * @return true if found the element end, false if need to read more. (This is the same as returning gotElementEnd().)
    */
   bool 
-  findElementEnd(uint8_t *input, unsigned int inputLength) 
+  findElementEnd(uint8_t *input, size_t inputLength) 
   {
     ndn_Error error;
     if ((error = ndn_BinaryXmlStructureDecoder_findElementEnd(this, input, inputLength)))
@@ -39,7 +39,7 @@
     return gotElementEnd();
   }
   
-  unsigned int 
+  size_t 
   getOffset() const { return offset; }
   
   bool 
diff --git a/ndn-cpp/encoding/binary-xml-wire-format.cpp b/ndn-cpp/encoding/binary-xml-wire-format.cpp
index 130412c..adb756a 100644
--- a/ndn-cpp/encoding/binary-xml-wire-format.cpp
+++ b/ndn-cpp/encoding/binary-xml-wire-format.cpp
@@ -46,7 +46,7 @@
 }
 
 void 
-BinaryXmlWireFormat::decodeInterest(Interest& interest, const uint8_t *input, unsigned int inputLength)
+BinaryXmlWireFormat::decodeInterest(Interest& interest, const uint8_t *input, size_t inputLength)
 {
   struct ndn_NameComponent nameComponents[100];
   struct ndn_ExcludeEntry excludeEntries[100];
@@ -64,7 +64,7 @@
 }
 
 Blob 
-BinaryXmlWireFormat::encodeData(const Data& data, unsigned int *signedPortionBeginOffset, unsigned int *signedPortionEndOffset) 
+BinaryXmlWireFormat::encodeData(const Data& data, size_t *signedPortionBeginOffset, size_t *signedPortionEndOffset) 
 {
   struct ndn_NameComponent nameComponents[100];
   struct ndn_NameComponent keyNameComponents[100];
@@ -84,7 +84,7 @@
 
 void 
 BinaryXmlWireFormat::decodeData
-  (Data& data, const uint8_t *input, unsigned int inputLength, unsigned int *signedPortionBeginOffset, unsigned int *signedPortionEndOffset)
+  (Data& data, const uint8_t *input, size_t inputLength, size_t *signedPortionBeginOffset, size_t *signedPortionEndOffset)
 {
   struct ndn_NameComponent nameComponents[100];
   struct ndn_NameComponent keyNameComponents[100];
@@ -119,7 +119,7 @@
 }
 
 void 
-BinaryXmlWireFormat::decodeForwardingEntry(ForwardingEntry& forwardingEntry, const uint8_t *input, unsigned int inputLength)
+BinaryXmlWireFormat::decodeForwardingEntry(ForwardingEntry& forwardingEntry, const uint8_t *input, size_t inputLength)
 {
   struct ndn_NameComponent prefixNameComponents[100];
   struct ndn_ForwardingEntry forwardingEntryStruct;
diff --git a/ndn-cpp/encoding/binary-xml-wire-format.hpp b/ndn-cpp/encoding/binary-xml-wire-format.hpp
index de1388e..c169669 100644
--- a/ndn-cpp/encoding/binary-xml-wire-format.hpp
+++ b/ndn-cpp/encoding/binary-xml-wire-format.hpp
@@ -32,7 +32,7 @@
    * @param inputLength The number of bytes in input.
    */
   virtual void 
-  decodeInterest(Interest& interest, const uint8_t *input, unsigned int inputLength);
+  decodeInterest(Interest& interest, const uint8_t *input, size_t inputLength);
 
   /**
    * Encode data with binary XML and return the encoding.
@@ -45,7 +45,7 @@
    */
   virtual Blob 
   encodeData
-    (const Data& data, unsigned int *signedPortionBeginOffset, unsigned int *signedPortionEndOffset);
+    (const Data& data, size_t *signedPortionBeginOffset, size_t *signedPortionEndOffset);
   
   /**
    * Decode input as a data packet in binary XML and set the fields in the data object.
@@ -54,14 +54,14 @@
    * @param inputLength The number of bytes in input.
    * @param signedPortionBeginOffset Return the offset in the input buffer of the beginning of the signed portion.
    * If you are not decoding in order to verify, you can call 
-   * decodeData(Data& data, const uint8_t *input, unsigned int inputLength) to ignore this returned value.
+   * decodeData(Data& data, const uint8_t *input, size_t inputLength) to ignore this returned value.
    * @param signedPortionEndOffset Return the offset in the input buffer of the end of the signed portion.
    * If you are not decoding in order to verify, you can call 
-   * decodeData(Data& data, const uint8_t *input, unsigned int inputLength) to ignore this returned value.
+   * decodeData(Data& data, const uint8_t *input, size_t inputLength) to ignore this returned value.
    */  
   virtual void 
   decodeData
-    (Data& data, const uint8_t *input, unsigned int inputLength, unsigned int *signedPortionBeginOffset, unsigned int *signedPortionEndOffset);
+    (Data& data, const uint8_t *input, size_t inputLength, size_t *signedPortionBeginOffset, size_t *signedPortionEndOffset);
 
   /**
    * Encode forwardingEntry in binary XML and return the encoding. 
@@ -78,7 +78,7 @@
    * @param inputLength The number of bytes in input.
    */
   virtual void 
-  decodeForwardingEntry(ForwardingEntry& forwardingEntry, const uint8_t *input, unsigned int inputLength);
+  decodeForwardingEntry(ForwardingEntry& forwardingEntry, const uint8_t *input, size_t inputLength);
 };
   
 }
diff --git a/ndn-cpp/encoding/wire-format.cpp b/ndn-cpp/encoding/wire-format.cpp
index 70644ad..cf7890e 100644
--- a/ndn-cpp/encoding/wire-format.cpp
+++ b/ndn-cpp/encoding/wire-format.cpp
@@ -35,20 +35,20 @@
 }
 
 void 
-WireFormat::decodeInterest(Interest& interest, const uint8_t *input, unsigned int inputLength) 
+WireFormat::decodeInterest(Interest& interest, const uint8_t *input, size_t inputLength) 
 {
   throw logic_error("unimplemented");
 }
 
 Blob 
-WireFormat::encodeData(const Data& data, unsigned int *signedPortionBeginOffset, unsigned int *signedPortionEndOffset) 
+WireFormat::encodeData(const Data& data, size_t *signedPortionBeginOffset, size_t *signedPortionEndOffset) 
 {
   throw logic_error("unimplemented");
 }
 
 void 
 WireFormat::decodeData
-  (Data& data, const uint8_t *input, unsigned int inputLength, unsigned int *signedPortionBeginOffset, unsigned int *signedPortionEndOffset) 
+  (Data& data, const uint8_t *input, size_t inputLength, size_t *signedPortionBeginOffset, size_t *signedPortionEndOffset) 
 {
   throw logic_error("unimplemented");
 }
@@ -60,7 +60,7 @@
 }
 
 void 
-WireFormat::decodeForwardingEntry(ForwardingEntry& forwardingEntry, const uint8_t *input, unsigned int inputLength) 
+WireFormat::decodeForwardingEntry(ForwardingEntry& forwardingEntry, const uint8_t *input, size_t inputLength) 
 {
   throw logic_error("unimplemented");
 }
diff --git a/ndn-cpp/encoding/wire-format.hpp b/ndn-cpp/encoding/wire-format.hpp
index 489415b..c5b4c6e 100644
--- a/ndn-cpp/encoding/wire-format.hpp
+++ b/ndn-cpp/encoding/wire-format.hpp
@@ -35,7 +35,7 @@
    * @throw logic_error for unimplemented if the derived class does not override.
    */
   virtual void 
-  decodeInterest(Interest& interest, const uint8_t *input, unsigned int inputLength);
+  decodeInterest(Interest& interest, const uint8_t *input, size_t inputLength);
 
   /**
    * Encode data and return the encoding.  Your derived class should override.
@@ -49,7 +49,7 @@
    */
   virtual Blob 
   encodeData
-    (const Data& data, unsigned int *signedPortionBeginOffset, unsigned int *signedPortionEndOffset);
+    (const Data& data, size_t *signedPortionBeginOffset, size_t *signedPortionEndOffset);
 
   /**
    * Encode data and return the encoding.
@@ -60,7 +60,7 @@
   Blob 
   encodeData(const Data& data)
   {
-    unsigned int dummyBeginOffset, dummyEndOffset;
+    size_t dummyBeginOffset, dummyEndOffset;
     return encodeData(data, &dummyBeginOffset, &dummyEndOffset);
   }
 
@@ -71,20 +71,20 @@
    * @param inputLength The number of bytes in input.
    * @param signedPortionBeginOffset Return the offset in the input buffer of the beginning of the signed portion.
    * If you are not decoding in order to verify, you can call 
-   * decodeData(Data& data, const uint8_t *input, unsigned int inputLength) to ignore this returned value.
+   * decodeData(Data& data, const uint8_t *input, size_t inputLength) to ignore this returned value.
    * @param signedPortionEndOffset Return the offset in the input buffer of the end of the signed portion.
    * If you are not decoding in order to verify, you can call 
-   * decodeData(Data& data, const uint8_t *input, unsigned int inputLength) to ignore this returned value.
+   * decodeData(Data& data, const uint8_t *input, size_t inputLength) to ignore this returned value.
    * @throw logic_error for unimplemented if the derived class does not override.
    */  
   virtual void 
   decodeData
-    (Data& data, const uint8_t *input, unsigned int inputLength, unsigned int *signedPortionBeginOffset, unsigned int *signedPortionEndOffset);
+    (Data& data, const uint8_t *input, size_t inputLength, size_t *signedPortionBeginOffset, size_t *signedPortionEndOffset);
 
   void 
-  decodeData(Data& data, const uint8_t *input, unsigned int inputLength)
+  decodeData(Data& data, const uint8_t *input, size_t inputLength)
   {
-    unsigned int dummyBeginOffset, dummyEndOffset;
+    size_t dummyBeginOffset, dummyEndOffset;
     decodeData(data, input, inputLength, &dummyBeginOffset, &dummyEndOffset);
   }
   
@@ -105,7 +105,7 @@
    * @throw logic_error for unimplemented if the derived class does not override.
    */
   virtual void 
-  decodeForwardingEntry(ForwardingEntry& forwardingEntry, const uint8_t *input, unsigned int inputLength);
+  decodeForwardingEntry(ForwardingEntry& forwardingEntry, const uint8_t *input, size_t inputLength);
 
   /**
    * Set the static default WireFormat used by default encoding and decoding methods.