diff --git a/lib/utilities.js b/lib/utilities.js
index fa36fde1..276daf12 100644
--- a/lib/utilities.js
+++ b/lib/utilities.js
@@ -276,20 +276,22 @@
             return ip;
         }
 
-        function iphash(ip, segment, len) {
+        function iphash(data, len) {
             var md5 = crypto.createHash("md5");
-            md5.update(ip);
-            md5.update(segment);
+            md5.update(data);
             return md5.digest("base64").substring(0, len);
         }
 
         function cloakIPv4(ip) {
             var parts = ip.split(".");
+            var accumulator = "";
 
             parts = parts.map(function (segment, i) {
                 if (i < 2) return segment;
 
-                return iphash(ip, segment + i, 3);
+                var part = iphash(accumulator + segment + i, 3);
+                accumulator += segment;
+                return part;
             });
 
             while (parts.length < 4) parts.push("*");
@@ -299,11 +301,14 @@
         function cloakIPv6(ip) {
             var parts = ip.split(":");
             parts.splice(4, 4);
+            var accumulator = "";
 
             parts = parts.map(function (segment, i) {
                 if (i < 2) return segment;
 
-                return iphash(ip, segment + i, 4);
+                var part = iphash(accumulator + segment + i, 4);
+                accumulator += segment;
+                return part;
             });
 
             while (parts.length < 4) parts.push("*");