diff --git a/EduNetworkBuilder/IPAddress.cs b/EduNetworkBuilder/IPAddress.cs
index 3c92bdd..9d0b1b7 100644
--- a/EduNetworkBuilder/IPAddress.cs
+++ b/EduNetworkBuilder/IPAddress.cs
@@ -330,7 +330,10 @@ namespace EduNetworkBuilder
         /// <summary>
         /// If the IP address has not yet been assigned
         /// </summary>
-        public bool IsUnassigned() { return Unset; }
+        public bool IsUnassigned() {
+            if (GetIPString == NB.ZeroIPString) return true; //Sometimes we use 0.0.0.0 as unset.
+            return Unset; 
+        }
 
         /// <summary>
         /// If the IP address is the same as the broadcast address
@@ -358,7 +361,7 @@ namespace EduNetworkBuilder
         /// </summary>
         public bool IsLoopback() 
         {
-            if (GetIPString == "127.0.0.1") return true;
+            if (GetIPString == NB.LoopbackIPString) return true;
             return false;
         }
 
@@ -407,12 +410,12 @@ namespace EduNetworkBuilder
 
         public NB_IPAddress BreakIPNetmaskZero()
         {
-            NB_IPAddress one = new NB_IPAddress(GetIPString, "0.0.0.0", myType);
+            NB_IPAddress one = new NB_IPAddress(GetIPString, NB.ZeroIPString, myType); //0.0.0.0
             return one;
         }
         public NB_IPAddress BreakIPNetmask32()
         {
-            NB_IPAddress one = new NB_IPAddress(GetIPString, "255.255.255.255", myType);
+            NB_IPAddress one = new NB_IPAddress(GetIPString, NB.BroadcastIPString, myType);  //255.255.255.0
             return one;
         }
         public NB_IPAddress BreakIPNetmaskRandom()
@@ -434,12 +437,12 @@ namespace EduNetworkBuilder
 
         public NB_IPAddress BreakIPAddressZero()
         {
-            NB_IPAddress one = new NB_IPAddress("0.0.0.0", GetIPString, myType);
+            NB_IPAddress one = new NB_IPAddress(NB.ZeroIPString, GetIPString, myType);
             return one;
         }
         public NB_IPAddress BreakIPAddress32()
         {
-            NB_IPAddress one = new NB_IPAddress("255.255.255.255", GetIPString, myType);
+            NB_IPAddress one = new NB_IPAddress(NB.BroadcastIPString, GetIPString, myType);
             return one;
         }
         public NB_IPAddress BreakIPAddressRandom()