diff --git a/tiramisu/config.py b/tiramisu/config.py
index 536aacf..dca0fef 100644
--- a/tiramisu/config.py
+++ b/tiramisu/config.py
@@ -506,7 +506,7 @@ class Config(CommonConfig):
     "main configuration management entry"
     __slots__ = tuple()
 
-    def __init__(self, descr, config_id=None, is_persistent=False):
+    def __init__(self, descr, session_id=None, is_persistent=False):
         """ Configuration option management master class
 
         :param descr: describes the configuration schema
@@ -514,7 +514,7 @@ class Config(CommonConfig):
         :param context: the current root config
         :type context: `Config`
         """
-        storage = get_storage(self, config_id, is_persistent)
+        storage = get_storage(self, session_id, is_persistent)
         self._impl_settings = Settings(self, storage)
         self._impl_values = Values(self, storage)
         super(Config, self).__init__(descr, self)
@@ -534,7 +534,7 @@ class Config(CommonConfig):
 class MetaConfig(CommonConfig):
     __slots__ = ('_impl_children',)
 
-    def __init__(self, children, meta=True, config_id=None, is_persistent=False):
+    def __init__(self, children, meta=True, session_id=None, is_persistent=False):
         if not isinstance(children, list):
             raise ValueError(_("metaconfig's children must be a list"))
         self._impl_descr = None
@@ -555,7 +555,7 @@ class MetaConfig(CommonConfig):
                 child._impl_meta = self
 
         self._impl_children = children
-        storage = get_storage(self, config_id, is_persistent)
+        storage = get_storage(self, session_id, is_persistent)
         self._impl_settings = Settings(self, storage)
         self._impl_values = Values(self, storage)
         self._impl_meta = None
diff --git a/tiramisu/setting.py b/tiramisu/setting.py
index 58059d7..edcccac 100644
--- a/tiramisu/setting.py
+++ b/tiramisu/setting.py
@@ -34,7 +34,7 @@ ro_append = ('frozen', 'disabled', 'validator', 'everything_frozen',
 rw_remove = ('permissive', 'everything_frozen', 'mandatory')
 rw_append = ('frozen', 'disabled', 'validator', 'hidden')
 default_properties = ('expire', 'validator')
-storage_type = 'sqlite3'
+storage_type = 'dictionary'
 
 
 class _const:
@@ -189,15 +189,15 @@ def set_storage(name):
     storage_type = name
 
 
-def get_storage(context, config_id, is_persistent):
+def get_storage(context, session_id, is_persistent):
     def gen_id(config):
         return str(id(config)) + str(time())
 
-    if config_id is None:
-        config_id = gen_id(context)
+    if session_id is None:
+        session_id = gen_id(context)
     import_lib = 'tiramisu.storage.{0}.storage'.format(storage_type)
     return __import__(import_lib, globals(), locals(), ['Storage'],
-                      -1).Storage(config_id, is_persistent)
+                      -1).Storage(session_id, is_persistent)
 
 
 #____________________________________________________________
diff --git a/tiramisu/storage/dictionary/storage.py b/tiramisu/storage/dictionary/storage.py
index 876f5da..759e5e0 100644
--- a/tiramisu/storage/dictionary/storage.py
+++ b/tiramisu/storage/dictionary/storage.py
@@ -20,13 +20,22 @@
 
 
 from tiramisu.i18n import _
+from tiramisu.error import ConfigError
+
+
+def enumerate():
+    return []
+
+
+def delete(session_id):
+    raise ConfigError(_('dictionary storage cannot delete session'))
 
 
 class Storage(object):
     __slots__ = tuple()
     storage = 'dictionary'
 
-    def __init__(self, config_id, is_persistent):
+    def __init__(self, session_id, is_persistent):
         if is_persistent:
             raise ValueError(_('a dictionary cannot be persistent'))
 
diff --git a/tiramisu/storage/sqlite3/storage.py b/tiramisu/storage/sqlite3/storage.py
index e9d5e08..8c5bc86 100644
--- a/tiramisu/storage/sqlite3/storage.py
+++ b/tiramisu/storage/sqlite3/storage.py
@@ -20,17 +20,38 @@
 
 from pickle import dumps, loads
 from os import unlink
+from os.path import basename, splitext, join
 import sqlite3
+from glob import glob
+
+
+extension = 'db'
+dir_database = '/tmp'
+
+
+def _gen_filename(name):
+    return join(dir_database, '{0}.{1}'.format(name, extension))
+
+
+def enumerate():
+    names = []
+    for filename in glob(_gen_filename('*')):
+        names.append(basename(splitext(filename)[0]))
+    return names
+
+
+def delete(session_id):
+    unlink(_gen_filename(session_id))
 
 
 class Storage(object):
-    __slots__ = ('_conn', '_cursor', 'is_persistent', 'db_file')
+    __slots__ = ('_conn', '_cursor', 'is_persistent', '_session_id')
     storage = 'sqlite3'
 
-    def __init__(self, config_id, is_persistent):
+    def __init__(self, session_id, is_persistent):
         self.is_persistent = is_persistent
-        self.db_file = config_id + '.db'
-        self._conn = sqlite3.connect(self.db_file)
+        self._session_id = session_id
+        self._conn = sqlite3.connect(_gen_filename(self._session_id))
         self._conn.text_factory = str
         self._cursor = self._conn.cursor()
 
@@ -52,7 +73,7 @@ class Storage(object):
         self._cursor.close()
         self._conn.close()
         if not self.is_persistent:
-            unlink(self.db_file)
+            delete(self._session_id)
 
 
 class Cache(object):