diff --git a/src/internet/model/ndisc-cache.cc b/src/internet/model/ndisc-cache.cc
index 6fa4f1afd..ea6ebb52c 100644
--- a/src/internet/model/ndisc-cache.cc
+++ b/src/internet/model/ndisc-cache.cc
@@ -97,7 +97,8 @@ NdiscCache::Entry* NdiscCache::Lookup (Ipv6Address dst)
   if (m_ndCache.find (dst) != m_ndCache.end ())
     {
       NdiscCache::Entry* entry = m_ndCache[dst];
-      NS_LOG_LOGIC ("Found an entry:" << dst << " to " << entry->GetMacAddress ());
+      NS_LOG_LOGIC ("Found an entry: " << *entry);
+
       return entry;
     }
   NS_LOG_LOGIC ("Nothing found");
@@ -114,7 +115,7 @@ std::list<NdiscCache::Entry*> NdiscCache::LookupInverse (Address dst)
       NdiscCache::Entry *entry = (*i).second;
       if (entry->GetMacAddress () == dst)
         {
-          NS_LOG_LOGIC ("Found an entry:" << (*i).first << " to " << (*i).second);
+          NS_LOG_LOGIC ("Found an entry:" << (*entry));
           entryList.push_back (entry);
         }
     }
@@ -214,13 +215,13 @@ void NdiscCache::PrintNdiscCache (Ptr<OutputStreamWrapper> stream)
           *os << " STALE\n";
         }
       else if (i->second->IsPermanent ())
-	{
-	  *os << " PERMANENT\n";
-	}
+        {
+          *os << " PERMANENT\n";
+        }
       else
-	{
-	  NS_FATAL_ERROR ("Test for possibly unreachable code-- please file a bug report, with a test case, if this is ever hit");
-	}
+        {
+          NS_FATAL_ERROR ("Test for possibly unreachable code-- please file a bug report, with a test case, if this is ever hit");
+        }
     }
 }
 
@@ -595,5 +596,37 @@ void NdiscCache::Entry::SetMacAddress (Address mac)
   m_macAddress = mac;
 }
 
+void NdiscCache::Entry::Print (std::ostream &os) const
+{
+  os << m_ipv6Address << " lladdr " << m_macAddress << " state ";
+  switch (m_state)
+  {
+    case INCOMPLETE:
+      os << "INCOMPLETE";
+      break;
+    case REACHABLE:
+      os << "REACHABLE";
+      break;
+    case STALE:
+      os << "STALE";
+      break;
+    case DELAY:
+      os << "DELAY";
+      break;
+    case PROBE:
+      os << "PROBE";
+      break;
+    case PERMANENT:
+      os << "PERMANENT";
+      break;
+  }
+}
+
+std::ostream& operator << (std::ostream& os, NdiscCache::Entry const& entry)
+{
+  entry.Print (os);
+  return os;
+}
+
 } /* namespace ns3 */
 
diff --git a/src/internet/model/ndisc-cache.h b/src/internet/model/ndisc-cache.h
index f7d4107c9..04d2196eb 100644
--- a/src/internet/model/ndisc-cache.h
+++ b/src/internet/model/ndisc-cache.h
@@ -89,7 +89,7 @@ public:
    * \param dst destination address.
    * \return the entry if found, 0 otherwise.
    */
-  NdiscCache::Entry* Lookup (Ipv6Address dst);
+  virtual NdiscCache::Entry* Lookup (Ipv6Address dst);
 
   /**
    * \brief Lookup in the cache for a MAC address.
@@ -103,7 +103,7 @@ public:
    * \param to address to add
    * \return an new Entry
    */
-  NdiscCache::Entry* Add (Ipv6Address to);
+  virtual NdiscCache::Entry* Add (Ipv6Address to);
 
   /**
    * \brief Delete an entry.
@@ -162,6 +162,8 @@ public:
      */
     Entry (NdiscCache* nd);
 
+    virtual ~Entry() = default;
+
     /**
      * \brief Changes the state to this entry to INCOMPLETE.
      * \param p packet that wait to be sent
@@ -342,6 +344,19 @@ public:
      */
     void SetIpv6Address (Ipv6Address ipv6Address);
 
+    /**
+     * \brief Print this entry to the given output stream.
+     *
+     * \param os the output stream to which this Ipv6Address is printed
+     */
+    void Print (std::ostream &os) const;
+
+protected:
+    /**
+     * \brief the NdiscCache associated.
+     */
+    NdiscCache* m_ndCache;
+
 private:
     /**
      * \brief The IPv6 address.
@@ -366,11 +381,6 @@ private:
      */
     NdiscCacheEntryState_e m_state;
 
-    /**
-     * \brief the NdiscCache associated.
-     */
-    NdiscCache* m_ndCache;
-
     /**
      * \brief The MAC address.
      */
@@ -402,7 +412,12 @@ private:
     uint8_t m_nsRetransmit;
   };
 
-private:
+protected:
+  /**
+   * \brief Dispose this object.
+   */
+  void DoDispose ();
+
   /**
    * \brief Neighbor Discovery Cache container
    */
@@ -412,6 +427,14 @@ private:
    */
   typedef sgi::hash_map<Ipv6Address, NdiscCache::Entry *, Ipv6AddressHash>::iterator CacheI;
 
+  /**
+   * \brief A list of Entry.
+   */
+  Cache m_ndCache;
+
+
+private:
+
   /**
    * \brief Copy constructor.
    *
@@ -427,11 +450,6 @@ private:
    */
   NdiscCache& operator= (NdiscCache const &);
 
-  /**
-   * \brief Dispose this object.
-   */
-  void DoDispose ();
-
   /**
    * \brief The NetDevice.
    */
@@ -447,17 +465,22 @@ private:
    */
   Ptr<Icmpv6L4Protocol> m_icmpv6;
 
-  /**
-   * \brief A list of Entry.
-   */
-  Cache m_ndCache;
-
   /**
    * \brief Max number of packet stored in m_waiting.
    */
   uint32_t m_unresQlen;
 };
 
+/**
+ * \brief Stream insertion operator.
+ *
+ * \param os the reference to the output stream
+ * \param entry the NdiscCache::Entry
+ * \returns the reference to the output stream
+ */
+std::ostream & operator << (std::ostream& os, NdiscCache::Entry const& entry);
+
+
 } /* namespace ns3 */
 
 #endif /* NDISC_CACHE_H */