diff --git a/include/application/application.h b/include/application/application.h
index 4788c83..9e88acb 100644
--- a/include/application/application.h
+++ b/include/application/application.h
@@ -33,6 +33,7 @@
 #include "storage/storage.h"
 #include "session.h"
 #include "user.h"
+#include "uuid.h"
 
 
 struct randval {
@@ -50,6 +51,12 @@ CLASS(Application) {
 
 	Storage           users;
 	Storage           passwords;
+	Storage           roles;
+
+	Uuid              user_namespace;
+
+	Hash              roles_user_index;
+	Hash              roles_resource_index;
 
 	const char *      version;
 };
diff --git a/include/auth/interface/auth.h b/include/auth/interface/auth.h
index 8dccfa2..9e4b696 100644
--- a/include/auth/interface/auth.h
+++ b/include/auth/interface/auth.h
@@ -31,9 +31,10 @@
 #include <stdarg.h>
 
 #include "class.h"
+#include "uuid.h"
 #include "auth/credential.h"
 
-typedef int (* fptr_authenticate)(void *, Credential);
+typedef int (* fptr_authenticate)(void *, Credential, Uuid);
 
 extern const struct interface i_Auth;
 
@@ -42,7 +43,7 @@ struct i_Auth {
 	fptr_authenticate              authenticate;
 };
 
-extern int authenticate(void *, Credential);
+extern int authenticate(void *, Credential, Uuid);
 
 #endif // __AUTH_INTERFACE_AUTH_H__
 
diff --git a/include/interface/indexable.h b/include/interface/indexable.h
new file mode 100644
index 0000000..74a037d
--- /dev/null
+++ b/include/interface/indexable.h
@@ -0,0 +1,49 @@
+/**
+ * \file
+ * This interface provides only one function at all.
+ * indexUuid will generate a uuid to the current object.
+ * 
+ * \todo
+ * Maybe merge hashable and indexable. Thus we might get an
+ * easy way to exchange the hashing mechanism used for my
+ * associative arrays.
+ *
+ * \author	Georg Hopp
+ *
+ * \copyright
+ * Copyright © 2012  Georg Hopp
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __INDEXABLE_H__
+#define __INDEXABLE_H__
+
+#include "uuid.h"
+
+
+typedef Uuid (* fptr_indexUuid)(void *, Uuid);
+
+extern const struct interface i_Indexable;
+
+struct i_Indexable {
+	const struct interface * const _;
+	fptr_indexUuid                 uuid;
+};
+
+extern Uuid indexUuid(void *, Uuid);
+
+#endif // __INDEXABLE_H__
+
+// vim: set ts=4 sw=4:
diff --git a/include/interface/serializable.h b/include/interface/serializable.h
new file mode 100644
index 0000000..742197e
--- /dev/null
+++ b/include/interface/serializable.h
@@ -0,0 +1,42 @@
+/**
+ * \file
+ *
+ * \author	Georg Hopp
+ *
+ * \copyright
+ * Copyright © 2012  Georg Hopp
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __SERIALIZABLE_H__
+#define __SERIALIZABLE_H__
+
+typedef void (* fptr_serialize)(void *, unsigned char **, size_t *);
+typedef void (* fptr_unserialize)(void *, const unsigned char *, size_t);
+
+extern const struct interface i_Serializable;
+
+struct i_Serializable {
+	const struct interface * const _;
+	fptr_serialize                 serialize;
+	fptr_unserialize               unserialize;
+};
+
+extern void serialize(void *, unsigned char **, size_t *);
+extern void unserialize(void *, const unsigned char *, size_t);
+
+#endif // __SERIALIZABLE_H__
+
+// vim: set ts=4 sw=4:
diff --git a/src/Makefile.am b/src/Makefile.am
index b3eaf63..a5fd50b 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -10,7 +10,9 @@ TRUTILS = utils/hash.c \
 	  utils/mime_type.c
 
 TRBASESRC = interface/subject.c \
-	    interface/observer.c
+	    interface/observer.c \
+	    interface/serializable.c \
+	    interface/indexable.c
 
 TRBASELIBS = class/libclass.la \
 	     cbuf/libcbuf.la \
diff --git a/src/application/application.c b/src/application/application.c
index 04eda1e..c9754f7 100644
--- a/src/application/application.c
+++ b/src/application/application.c
@@ -26,6 +26,7 @@
 
 #include "class.h"
 #include "hash.h"
+#include "uuid.h"
 #include "application/application.h"
 #include "storage/storage.h"
 
@@ -50,6 +51,9 @@ applicationCtor(void * _this, va_list * params)
 	 */
 	this->users     = va_arg(*params, Storage);
 	this->passwords = va_arg(*params, Storage);
+	//this->roles     = va_arg(*params, Storage);
+
+	this->user_namespace = uuidParse(va_arg(*params, char *));
 
 	// initialize authenticators to use.
 	this->nauth = va_arg(*params, size_t);
@@ -75,6 +79,8 @@ applicationDtor(void * _this)
 	Application this = _this;
 	size_t      i;
 
+	delete(this->user_namespace);
+
 	for (i=0; i<SESSION_LIVETIME; i++) {
 		delete(this->active_sessions[i]);
 	}
diff --git a/src/application/login.c b/src/application/login.c
index 237e16c..039e15e 100644
--- a/src/application/login.c
+++ b/src/application/login.c
@@ -28,6 +28,11 @@
 
 #include "class.h"
 #include "auth.h"
+#include "uuid.h"
+#include "storage/storage.h"
+
+#include "interface/serializable.h"
+#include "interface/indexable.h"
 
 #include "utils/memory.h"
 #include "application/application.h"
@@ -40,40 +45,63 @@ applicationLogin(
 		Session     session)
 {
 	size_t i;
+	Uuid   search;
+	int    authenticated = 0;
+
+	User   user = new(User, NULL);
+
+	user->email  = CRED_PWD(credential).user;
+	user->nemail = &CRED_PWD(credential).nuser;
+	search = indexUuid(user, this->user_namespace);
 
 	for (i=0; i<this->nauth; i++) {
-		if (authenticate(this->auth[i], credential)) {
-			session->user = new(User, NULL);
+		if (authenticate(this->auth[i], credential, search)) {
+			session->user = user;
 
 			switch (credential->type) {
 				case CRED_PASSWORD:
-					session->user->email  = CRED_PWD(credential).user;
-					session->user->nemail = &CRED_PWD(credential).nuser;
-
-					if (NULL == userLoad(session->user, this->users)) {
-						// this is an ldap user that has not yet set
-						// additional user informations.
-						/** \todo again...change the keys to id's */
-						session->user->email = NULL;
-						delete(session->user);
-						session->user = new(User,
-								CRED_PWD(credential).user,
-								CRED_PWD(credential).nuser,
-								CSTRA(""),
-								CSTRA(""));
-					}
+					{
+						char   * user_serialized;
+						size_t   nuser_serialized;
+
+						storageGet(
+								this->users, 
+								(char *)(search->uuid).value,
+								sizeof((search->uuid).value),
+								&user_serialized,
+								&nuser_serialized);
 
+						if (NULL != user_serialized) {
+							unserialize(
+									session->user,
+									(unsigned char *)user_serialized,
+									nuser_serialized);
+							MEM_FREE(user_serialized);
+						} else {
+							// this is a user authenticated via another method
+							// than the password database and has not yet set
+							// additional user informations.
+							session->user = NULL;
+							delete(session->user);
+							session->user = new(User,
+									CRED_PWD(credential).user,
+									CRED_PWD(credential).nuser,
+									CSTRA(""),
+									CSTRA(""));
+						}
+					}
 					break;
 
 				default:
 					break;
 			}
 
-			return 1;
+			authenticated = 1;
+			break;
 		}
 	}
 
-	return 0;
+	return authenticated;
 }
 
 // vim: set ts=4 sw=4:
diff --git a/src/application/session_cleanup.c b/src/application/session_cleanup.c
index 22f576a..0625464 100644
--- a/src/application/session_cleanup.c
+++ b/src/application/session_cleanup.c
@@ -43,7 +43,7 @@ applicationSessionCleanup(Application this, time_t now)
 	}
 
 	if (0 < expired && SESSION_LIVETIME > expired) {
-		Hash         * tmp_buf = memCalloc(SESSION_LIVETIME, sizeof(Hash));
+		Hash * tmp_buf = memCalloc(SESSION_LIVETIME, sizeof(Hash));
 
 		memcpy(
 				&(tmp_buf[expired]),
diff --git a/src/application/signup.c b/src/application/signup.c
index f6a3114..716deb3 100644
--- a/src/application/signup.c
+++ b/src/application/signup.c
@@ -29,8 +29,13 @@
 #include "class.h"
 #include "auth.h"
 #include "user.h"
+#include "uuid.h"
+#include "storage/storage.h"
 #include "application/application.h"
 
+#include "interface/serializable.h"
+#include "interface/indexable.h"
+
 #include "utils/memory.h"
 #include "commons.h"
 
@@ -44,17 +49,12 @@ applicationSignup(
 	unsigned char   hash_data[SALT_SIZE+HASH_SIZE];
 	unsigned char * salt = NULL;
 	unsigned char * hash = hash_data+SALT_SIZE;
+	char          * user_serialized;
+	size_t          nuser_serialized;
+	Uuid            index;
 
-	if (NULL != userLoad(user, this->users)) {
-		/*
-		 * if any user is found with this email return false
-		 * as on signup equal email adresses are not allowed
-		 * at all.
-		 */
-		return 0;
-	}
-
-	userSave(user, this->users);
+	index = indexUuid(user, this->user_namespace);
+	serialize(user, (unsigned char **)&user_serialized, &nuser_serialized);
 
 	if (FALSE == hash_pw(
 				CRED_PWD(cred).pass,
@@ -69,13 +69,23 @@ applicationSignup(
 	}
 
 	memcpy(hash_data, salt, SALT_SIZE);
-
 	MEM_FREE(salt);
 
+	/**
+	 * \todo
+	 * Add error handling here...
+	 */
+	storagePut(
+			this->users,
+			(char *)(index->uuid).value,
+			sizeof((index->uuid).value),
+			user_serialized,
+			nuser_serialized);
+
 	storagePut(
 			this->passwords,
-			CRED_PWD(cred).user,
-			CRED_PWD(cred).nuser,
+			(char *)(index->uuid).value,
+			sizeof((index->uuid).value),
 			(char *)hash_data,
 			SALT_SIZE + HASH_SIZE);
 
diff --git a/src/auth/interface/auth.c b/src/auth/interface/auth.c
index fa98183..a2745d6 100644
--- a/src/auth/interface/auth.c
+++ b/src/auth/interface/auth.c
@@ -20,6 +20,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include "uuid.h"
 #include "auth/auth.h"
 #include "auth/credential.h"
 #include "auth/interface/auth.h"
@@ -30,11 +31,11 @@ const struct interface i_Auth = {
 };
 
 int
-authenticate(void * auth, Credential cred)
+authenticate(void * auth, Credential cred, Uuid user_index)
 {
 	int ret;
 
-	RETCALL(auth, Auth, authenticate, ret, cred);
+	RETCALL(auth, Auth, authenticate, ret, cred, user_index);
 
 	return ret;
 }
diff --git a/src/auth/ldap.c b/src/auth/ldap.c
index efffdf1..82c9f8e 100644
--- a/src/auth/ldap.c
+++ b/src/auth/ldap.c
@@ -27,6 +27,7 @@
 #include <ldap.h>
 
 #include "class.h"
+#include "uuid.h"
 #include "utils/memory.h"
 #include "commons.h"
 
@@ -69,7 +70,7 @@ authLdapDtor(void * _this)
 
 static
 int
-authLdapAuthenticate(void * _this, Credential cred)
+authLdapAuthenticate(void * _this, Credential cred, Uuid user_index)
 {
 	AuthLdap this = _this;
 	char     who[256];
diff --git a/src/auth/storage/storage.c b/src/auth/storage/storage.c
index f8eef61..4210ebc 100644
--- a/src/auth/storage/storage.c
+++ b/src/auth/storage/storage.c
@@ -23,6 +23,8 @@
 #include "class.h"
 #include "storage/storage.h"
 #include "auth.h"
+#include "uuid.h"
+#include "user.h"
 #include "commons.h"
 #include "utils/memory.h"
 
@@ -45,7 +47,7 @@ authStorageDtor(void * _this)
 
 static
 int
-authStorageAuthenticate(void * _this, Credential cred)
+authStorageAuthenticate(void * _this, Credential cred, Uuid user_index)
 {
 	AuthStorage this = _this;
 
@@ -59,8 +61,8 @@ authStorageAuthenticate(void * _this, Credential cred)
 
 	storageGet(
 			this->store,
-			CRED_PWD(cred).user,
-			CRED_PWD(cred).nuser,
+			(char *)(user_index->uuid).value,
+			sizeof((user_index->uuid).value),
 			(char **)&found_hash,
 			&nfound_hash);
 
diff --git a/src/user/save.c b/src/interface/indexable.c
similarity index 65%
rename from src/user/save.c
rename to src/interface/indexable.c
index f4280d2..82f734f 100644
--- a/src/user/save.c
+++ b/src/interface/indexable.c
@@ -20,32 +20,23 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <sys/types.h>
-#include <string.h>
-
-#include "user.h"
-#include "storage/storage.h"
 #include "class.h"
+#include "uuid.h"
+#include "interface/indexable.h"
 
-#include "utils/memory.h"
-
+const struct interface i_Indexable = {
+	"indexable",
+	1
+};
 
-void
-userSave(User this, Storage storage)
+Uuid
+indexUuid(void * indexable, Uuid namespace)
 {
-	size_t storage_size =
-		*this->nemail + 1 +
-		*this->nfirstname + 1 +
-		*this->nsurname + 1 +
-		3 * sizeof(size_t);
+	Uuid ret;
+
+	RETCALL(indexable, Indexable, uuid, ret, namespace);
 
-	/**
-	 * \todo user return value for error handling 
-	 */
-	storageUpdate(
-			storage,
-			this->id, 36,
-			this->email, storage_size);
+	return ret;
 }
 
 // vim: set ts=4 sw=4:
diff --git a/src/user/load.c b/src/interface/serializable.c
similarity index 50%
rename from src/user/load.c
rename to src/interface/serializable.c
index bc25453..528e3fb 100644
--- a/src/user/load.c
+++ b/src/interface/serializable.c
@@ -20,48 +20,30 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <sys/types.h>
-#include <string.h>
-
-#include "user.h"
-#include "storage/storage.h"
 #include "class.h"
-
-#include "utils/memory.h"
-
-
-User
-userLoad(User this, Storage storage)
+#include "interface/serializable.h"
+
+const struct interface i_Serializable = {
+	"serializable",
+	2
+};
+
+void
+serialize(
+		void           *  serializable,
+		unsigned char ** serialized,
+		size_t         *  nserialized)
 {
-	char   * storage_data;
-	size_t   nstorage_data;
-	size_t * user_data_sizes;
-
-	if (NULL == storage) {
-		return NULL;
-	}
-
-	storageGet(
-			storage,
-			this->email, *this->nemail,
-			&storage_data, &nstorage_data);
-
-	if (NULL == storage_data) {
-		return NULL;
-	}
-
-	user_data_sizes =
-		(size_t *)(storage_data + nstorage_data - 3 * sizeof(size_t));
-
-	this->nemail     = user_data_sizes;
-	this->nfirstname = user_data_sizes + 1;
-	this->nsurname   = user_data_sizes + 2;
+	CALL(serializable, Serializable, serialize, serialized, nserialized);
+}
 
-	this->email     = storage_data;
-	this->firstname = this->email + *this->nemail + 1;
-	this->surname   = this->firstname + *this->nfirstname + 1;
-	
-	return this;
+void
+unserialize(
+		void                * serializable,
+		const unsigned char * serialized,
+		size_t                nserialized)
+{
+	CALL(serializable, Serializable, unserialize, serialized, nserialized);
 }
 
 // vim: set ts=4 sw=4:
diff --git a/src/taskrambler.c b/src/taskrambler.c
index 1565916..7103951 100644
--- a/src/taskrambler.c
+++ b/src/taskrambler.c
@@ -207,6 +207,7 @@ main()
 						value,
 						users,
 						passwords,
+						"14de9e60-d497-4754-be72-f3bed52541fc",
 						2,
 						authLdap,
 						authStorage);
diff --git a/src/user/Makefile.am b/src/user/Makefile.am
index 3c1af04..6b8174b 100644
--- a/src/user/Makefile.am
+++ b/src/user/Makefile.am
@@ -5,5 +5,5 @@ AM_CFLAGS += -I../../include/
 
 noinst_LTLIBRARIES = libuser.la
 
-libuser_la_SOURCES = user.c load.c save.c
+libuser_la_SOURCES = user.c
 libuser_la_CFLAGS  = $(AM_CFLAGS)
diff --git a/src/user/user.c b/src/user/user.c
index db77a10..e7cdb10 100644
--- a/src/user/user.c
+++ b/src/user/user.c
@@ -21,9 +21,12 @@
  */
 
 #include "user.h"
-#include "storage/storage.h"
+#include "uuid.h"
 #include "class.h"
 
+#include "interface/serializable.h"
+#include "interface/indexable.h"
+
 #include "utils/memory.h"
 
 
@@ -31,9 +34,8 @@ static
 int
 userCtor(void * _this, va_list * params)
 {
-	User this = _this;
-
-	char   * email      = va_arg(* params, char *);
+	User   this  = _this;
+	char * email = va_arg(* params, char *);
 
 	if (NULL != email) {
 		size_t   nemail     = va_arg(* params, size_t);
@@ -84,7 +86,66 @@ userDtor(void * _this)
 	}
 }
 
+static
+void
+userSerialize(
+		void           * _this,
+		unsigned char ** serialized,
+		size_t         * nserialized)
+{
+	User this = _this;
+
+	*nserialized =
+		*this->nemail + 1 +
+		*this->nfirstname + 1 +
+		*this->nsurname + 1 + 
+		3 * sizeof(size_t); 
+
+	*serialized = memMalloc(*nserialized);
+
+	memcpy(*serialized, this->email, *nserialized);
+}
+
+static
+void
+userUnserialize(
+		void                * _this,
+		const unsigned char * serialized,
+		size_t                nserialized)
+{
+	User     this = _this;
+	size_t * user_data_sizes;
+
+	this->email = memMalloc(nserialized);
+	memcpy(this->email, serialized, nserialized);
+
+	user_data_sizes =
+		(size_t *)(this->email + nserialized - 3 * sizeof(size_t));
+
+	this->nemail     = user_data_sizes;
+	this->nfirstname = user_data_sizes + 1;
+	this->nsurname   = user_data_sizes + 2;
+
+	this->firstname = this->email + *this->nemail + 1;
+	this->surname   = this->firstname + *this->nfirstname + 1;
+}
+
+static
+Uuid
+userIndexUuid(void * _this, Uuid namespace)
+{
+	User this = _this;
+
+	return uuidVersion3(
+			(unsigned char *)this->email,
+			*this->nemail,
+			namespace);
+}
+
+
 INIT_IFACE(Class, userCtor, userDtor, NULL);
-CREATE_CLASS(User, NULL, IFACE(Class));
+INIT_IFACE(Serializable, userSerialize, userUnserialize);
+INIT_IFACE(Indexable, userIndexUuid);
+CREATE_CLASS(User, NULL, IFACE(Class), IFACE(Serializable), IFACE(Indexable));
 
 // vim: set ts=4 sw=4: