diff --git a/src/node/ipv4-address.cc b/src/node/ipv4-address.cc
index 86d02792a..ca36d8083 100644
--- a/src/node/ipv4-address.cc
+++ b/src/node/ipv4-address.cc
@@ -230,6 +230,14 @@ std::ostream& operator<< (std::ostream& os, Ipv4Mask const& mask)
   mask.Print (os);
   return os;
 }
+bool operator == (Ipv4Mask const &a, Ipv4Mask const &b)
+{
+  return a.IsEqual (b);
+}
+bool operator != (Ipv4Mask const &a, Ipv4Mask const &b)
+{
+  return !a.IsEqual (b);
+}
 
 
 }; // namespace ns3
diff --git a/src/node/ipv4-address.h b/src/node/ipv4-address.h
index f99ad9ed4..a0714ac26 100644
--- a/src/node/ipv4-address.h
+++ b/src/node/ipv4-address.h
@@ -126,7 +126,9 @@ class Ipv4AddressHash : public std::unary_function<Ipv4Address, size_t> {
 public:
   size_t operator()(Ipv4Address const &x) const;
 };
-bool operator != (Ipv4Address const &a, Ipv4Address const &b);
+
+bool operator == (Ipv4Mask const &a, Ipv4Mask const &b);
+bool operator != (Ipv4Mask const &a, Ipv4Mask const &b);
 
 }; // namespace ns3