diff --git a/lib/bcoin/wallet.js b/lib/bcoin/wallet.js
index 822efd95..96038bdf 100644
--- a/lib/bcoin/wallet.js
+++ b/lib/bcoin/wallet.js
@@ -2720,6 +2720,13 @@ MasterKey.prototype.fromRaw = function fromRaw(raw) {
   if (this.encrypted) {
     this.iv = p.readVarBytes();
     this.ciphertext = p.readVarBytes();
+
+    // Future-proofing:
+    assert(p.readU8() === 0);
+    assert(p.readU32() === 50000);
+    assert(p.readU32() === 0);
+    assert(p.readU32() === 0);
+
     return this;
   }
 
@@ -2767,20 +2774,22 @@ MasterKey.fromKey = function fromKey(key) {
  */
 
 MasterKey.prototype.toJSON = function toJSON() {
-  var iv, ciphertext, key;
-
   if (this.encrypted) {
-    iv = this.iv.toString('hex');
-    ciphertext = this.ciphertext.toString('hex');
-  } else {
-    key = this.key.toJSON();
+    return {
+      encrypted: true,
+      iv: this.iv.toString('hex'),
+      ciphertext: this.ciphertext.toString('hex'),
+      // Future-proofing:
+      algorithm: 'pbkdf2',
+      N: 50000,
+      r: 0,
+      p: 0
+    };
   }
 
   return {
-    encrypted: this.encrypted,
-    iv: iv,
-    ciphertext: ciphertext,
-    key: key
+    encrypted: false,
+    key: this.key.toJSON()
   };
 };
 
@@ -2798,6 +2807,11 @@ MasterKey.prototype.fromJSON = function fromJSON(json) {
   if (json.encrypted) {
     assert(typeof json.iv === 'string');
     assert(typeof json.ciphertext === 'string');
+    // Future-proofing:
+    assert(json.algorithm === 'pbkdf2');
+    assert(json.N === 50000);
+    assert(json.r === 0);
+    assert(json.p === 0);
     this.iv = new Buffer(json.iv, 'hex');
     this.ciphertext = new Buffer(json.ciphertext, 'hex');
   } else {