diff --git a/js/models/core/Structure.js b/js/models/core/Structure.js
new file mode 100644
index 000000000..eaedb88e7
--- /dev/null
+++ b/js/models/core/Structure.js
@@ -0,0 +1,40 @@
+'use strict';
+
+
+var imports     = require('soop').imports();
+
+function Structure() {
+}
+
+
+/*
+ * Based on https://github.com/maraoz/bips/blob/master/bip-NNNN.mediawiki
+ * m / purpose' / cosigner_index / change / address_index 
+ */
+var PURPOSE = 45;
+var MAX_NON_HARDENED = 0x8000000 - 1;
+
+var SHARED_INDEX = MAX_NON_HARDENED - 0;
+var ID_INDEX = MAX_NON_HARDENED - 1;
+
+var BIP45_PUBLIC_PREFIX = 'm/'+ PURPOSE+'\'';
+Structure.BIP45_PUBLIC_PREFIX = BIP45_PUBLIC_PREFIX;
+
+Structure.Branch = function(address_index, isChange, cosigner_index) {
+  var ret = 'm/'+
+    (typeof cosigner_index !== 'undefined'? cosigner_index: SHARED_INDEX)+'/'+
+    (isChange?1:0)+'/'+
+    address_index;
+  return ret;
+};
+
+Structure.FullBranch = function(address_index, isChange, cosigner_index) {
+  var sub = Structure.Branch(address_index, isChange, cosigner_index);
+  sub = sub.substring(2);
+  return BIP45_PUBLIC_PREFIX + '/' + sub;
+};
+Structure.IdFullBranch = Structure.FullBranch(0, 0, ID_INDEX);
+Structure.IdBranch = Structure.Branch(0, 0, ID_INDEX);
+
+
+module.exports = require('soop')(Structure);