diff --git a/sstpd/address.py b/sstpd/address.py
index 9555b46..2d83902 100644
--- a/sstpd/address.py
+++ b/sstpd/address.py
@@ -20,6 +20,8 @@ def _next_host(self):
 
 
     def register(self, address):
+        if isinstance(address, str):
+            address = address.decode()
         addr = ipaddress.ip_address(address)
         if addr in self._pool:
             raise RegisteredException()
@@ -45,6 +47,8 @@ def apply(self):
 
 
     def unregister(self, address):
+        if isinstance(address, str):
+            address = address.decode()
         addr = ipaddress.ip_address(address)
         try:
             self._pool.remove(addr)