diff --git a/Technical.notes/asterisk-chan-sccp-config-handling.txt b/Technical.notes/asterisk-chan-sccp-config-handling.txt
new file mode 100644
index 0000000..dc39004
--- /dev/null
+++ b/Technical.notes/asterisk-chan-sccp-config-handling.txt
@@ -0,0 +1,91 @@
+Config Structure & Handling explained
+-------------------------------------
+Asterisk has a config parsing system that provides a generic interface to
+config sections and paramater, this system has multiple backends like
+ini, ldap, database that all present their data in a unified structure.
+
+From chan-sccp's view all the config sections and parameters looks exactly
+the same. In principal we don't have to know where the settings are coming
+from, we just need to be able to handle three cases:
+- requested section+paramater does not exist -> error
+- requested section+parameter exists and returns a value
+- requested section+parameter exists and returns NULL (ie: no field present in
+ini/table or is set to NULL)
+
+Based on this simple view of the world we built sccp_config.c and it's
+primary source of information sccp_config_entries.hh. The latter contains:
+- all valid config sections and parameters
+- their links to the in memory entity structures (POD's)
+- flags:
+  - their deprecated/obsolete status
+  - their value inheritance structure, device or lines can inherit values from
+the [general] section if they are not provided (See more about inheritance
+below)
+  - what to do when a value changes (either directly or through inheritance)
+- ultimate fallback value for parameter that cannot be/work `unspecified`
+- dedicated parser required to process the value, if a generic parser would
+not work (for example handling codecs, deny/permit)
+- help descriptions for each parameter
+
+Config value inheritance
+------------------------
+sccp_config_entries.hh contains universal fallback values for parameters
+that cannot work without one. Without this ultimate fallback
+value, chan-sccp would crash/not work. For example chan-sccp would not know
+what tcp-port to use for it's listerning connection, if not provided.
+They are built-in fallback values fixed at compile time.
+
+sccpdevices or sccplines can inherit values from the general section 
+in sccp.conf. The parameters in the general section are further backed by
+the sccp_config_entries.hh with it's fallback value, in case they
+are not provided.
+
+So for example:
+If sccpdevice:keepalive is not set, it will get it's value from
+general:keepalive, which if not set, will fallback to the value provided
+in sccp_config_entries.hh. The actual sccpdevice:keepalive is on evaluated
+at the moment the device is connecting and registering to chan-sccp, at
+which moment the value trickles down. So let's assume this situation:
+
+sccp.conf:
+```
+[general]
+;keepalive=120
+
+[SEPxxxxx]
+;keepalive=140
+```
+
+In this case the universal default will be provided by
+sccp_config_entries.hh. When we now set general:keepalive to 120 and issue
+`sccp reload`, all devices will have to be restart (RESTART_REQUIRED flag
+is set for keepalive in sccp_config_entries.hh). They will start to connect
+again, and the keepalive parameter is reevalueated, they will now see that
+they do not have a personal keepalive parameter provided and will use the
+general one, instead.
+
+Note: inheritance is specifically specified in the sccp_config_entries.hh
+file and just not automatically happen just based on the parameter name for
+example.
+
+You can think of the sccp_config_entries.hh and a universal section in the
+sccp.conf that has a slew of fallback values that are there to have your
+back. It will allow you to get by with a minimal config file without having
+to worry about chan-sccp not working, becasue you forgot to set the port
+number for example.
+
+So mentally you can think of it like this:
+```
+[universal]
+keepalive=60
+
+[general]
+;keepalive=120
+
+[SEPxxxxx]
+;keepalive=140
+```
+
+Note: changing sccp_config_entries.hh after the binary has been build, will
+not do anything, the fallback values are backed into the final binary at
+compile time.
diff --git a/install.php b/install.php
index 77b9083..2ac7674 100644
--- a/install.php
+++ b/install.php
@@ -105,7 +105,6 @@ function Get_DB_config($sccp_compatible)
             '_loginname' => array('create' => 'VARCHAR(20) NULL DEFAULT NULL AFTER `_hwlang`'),
             '_profileid' => array('create' => "INT(11) NOT NULL DEFAULT '0' AFTER `_loginname`"),
             '_dialrules' => array('create' => "VARCHAR(255) NULL DEFAULT NULL AFTER `_profileid`"),
-
             'useRedialMenu' => array('create' => "enum('yes','no') NOT NULL default 'no'", 'modify' => "enum('yes','no')"),
             'dtmfmode' => array('drop' => "yes"),
             'force_dtmfmode' => array('create' => "ENUM('auto','rfc2833','skinny') NOT NULL default 'auto'",
@@ -678,6 +677,7 @@ function InstallDB_CreateSccpDeviceConfigView($sccp_compatible)
             LEFT JOIN sccpuser sccpuser ON ( sccpuser.name = sccpdevice._loginname )
             GROUP BY sccpdevice.name;";
     }
+
     $results = $db->query($sql);
     if (DB::IsError($results)) {
         die_freepbx(sprintf(_("Error updating sccpdeviceconfig view. Command was: %s; error was: %s "), $sql, $results->getMessage()));
diff --git a/sccpManClasses/xmlinterface.class.php b/sccpManClasses/xmlinterface.class.php
index 1c40ed0..a3f8f45 100644
--- a/sccpManClasses/xmlinterface.class.php
+++ b/sccpManClasses/xmlinterface.class.php
@@ -287,22 +287,23 @@ class xmlinterface
                     break;
                 case 'loadinformation':
 //                      Set Path Image ????
-                    if (isset($dev_config["tftp_firmware"])) {
-                        $xml_work->$key = (isset($dev_config["loadimage"])) ? $dev_config["tftp_firmware"] . $dev_config["loadimage"] : '';
-                    } else {
-                        $xml_work->$key = (isset($dev_config["loadimage"])) ? $dev_config["loadimage"] : '';
-                    }
-                    if (!empty($dev_config['addon'])) {
-                        $xnode = $xml_work->addChild('addOnModules');
-                        $ti = 1;
-                        $hw_addon = explode(',', $dev_config['addon']);
-                        foreach ($hw_addon as $add_key) {
-                            if (!empty($dev_config['addon_info'][$add_key])) {
-                                $add_val = $dev_config['addon_info'][$add_key];
-                                $xnode_obj = $xnode->addChild('addOnModule');
-                                $xnode_obj->addAttribute('idx', $ti);
-                                $xnode_obj->addChild('loadInformation', $add_val);
-                                $ti++;
+                        if (isset($dev_config["tftp_firmware"])) {
+                            $xml_work->$key = (isset($dev_config["loadimage"])) ? $dev_config["tftp_firmware"] . $dev_config["loadimage"] : '';
+                        } else {
+                            $xml_work->$key = (isset($dev_config["loadimage"])) ? $dev_config["loadimage"] : '';
+                        }
+                        if (!empty($dev_config['addon'])) {
+                            $xnode = $xml_work->addChild('addOnModules');
+                            $ti = 1;
+                            $hw_addon = explode(';', $dev_config['addon']);
+                            foreach ($hw_addon as $add_key) {
+                                if (!empty($dev_config['addon_info'][$dev_config['addon']])) {
+                                    $add_val = $dev_config['addon_info'][$dev_config['addon']];
+                                    $xnode_obj = $xnode->addChild('addOnModule');
+                                    $xnode_obj->addAttribute('idx', $ti);
+                                    $xnode_obj->addChild('loadInformation', $add_val);
+                                    $ti++;
+                                }
                             }
                         }
                     }
@@ -615,11 +616,15 @@ class xmlinterface
                         if (!empty($dev_config['addon'])) {
                             $xnode = $xml_work->addChild('addOnModules');
                             $ti = 1;
-                            foreach ($dev_config['addon_info'] as $add_key => $add_val) {
-                                $xnode_obj = $xnode->addChild('addOnModule');
-                                $xnode_obj->addAttribute('idx', $ti);
-                                $xnode_obj->addChild('loadInformation', $add_val);
-                                $ti++;
+                            $hw_addon = explode(';', $dev_config['addon']);
+                            foreach ($hw_addon as $add_key) {
+                                if (!empty($dev_config['addon_info'][$dev_config['addon']])) {
+                                    $add_val = $dev_config['addon_info'][$dev_config['addon']];
+                                    $xnode_obj = $xnode->addChild('addOnModule');
+                                    $xnode_obj->addAttribute('idx', $ti);
+                                    $xnode_obj->addChild('loadInformation', $add_val);
+                                    $ti++;
+                                }
                             }
                         }
                         break;