- updated documentation for version 2.1.0

CHANGELOG

@@ -1,5 +1,6 @@
 Changes to version 2.1.0
 ------------------------
+- CS104 slave: added support for multiple redundancy groups
 - added non-threaded moded for CS 104 slave
 - separated thread and semaphore support for CS 104 slave
 - CS101 unbalanced link layer (master): automatically send request UD 1 when ACD bit is set in received frame

README.md

@@ -7,7 +7,9 @@ The current implementation contains code for the IEC 60870-5-101 (application la
 Features:
 - support for all application layer message types
 - master and slave
-- balanced and unbalanced link layers
+- balanced and unbalanced link layers (for CS 101 serial communication)
+- client/server for CS 104 TCP/IP communication
+- CS 104 redundancy group support
 - portable C99 code
 
 Please also consider the User Guide.
@@ -38,7 +40,7 @@ the project folder and run cmake to create the build files:
 ## Building without common code and HAL
 
 The library contains some common code and a platform abstraction layer (HAL) that is shared with
-other protocol libraries of MZ Automation (e.g. libiec61850). In order to simplify using these 
+other protocol libraries of MZ Automation (e.g. libiec61850). In order to simplify using these
 protocol libraries together it is possible to compile the library without the common parts.
 
 This can be done by using the *WITHOUT_HAL* and *WITHOUT_COMMON* defines when calling make:

user_guide.adoc

@@ -1,4 +1,4 @@
-= lib60870-C 2.0.0 User Guide
+= lib60870-C 2.1.0 User Guide
 Copyright 2018 MZ Automation GmbH
 
 == Introduction
@@ -13,6 +13,7 @@ Here is a list of supported features:
 * CS 104 (IEC 60870-5-104) client and server TCP/IP communication
 * CS 104 supports encrypted and authenticated TLS communication
 * CS 104 uses the CS 101 application layer
+* CS 104 slave: support for redundancy groups
 * Master/Client supports sending system commands, process commands, parameter commands, and data messages in reverse direction.
 * Slave/Server supports sending data messages in monitoring direction and commands in reverse direction
 * The list of supported ASDU types can be found in the annex
@@ -370,6 +371,58 @@ To configure and setup an IEC 60870-5-104 server/slave an instance of the _CS104
 
 After the server instance is created it can be configured
 
+=== CS104 Server mode
+
+The server provides three different modes concerning the support of redundant connections and event queue handling:
+
+The default mode (_CS104_MODE_SINGLE_REDUNDANCY_GROUP_) allows only a *single active client connection*. An active client connection is a connection
+where ASDUs (application data units) are sent. All other connections are only standby connections that don't send application layer data.
+There is a single queue for events. Events are also stored when no client is connected or when no connection is active.
+
+
+The second mode (_CS104_MODE_CONNECTION_IS_REDUNDANCY_GROUP_) allows *multiple active client connections*. Every connection has its own event queue.
+The event queue will be deleted when the client connection is closed. This mode can be used when more than one client has to access the
+application data. This mode is easy to use. But the drawback of this mode is that events are lost when no client is connected.
+
+The third mode (_CS104_MODE_MULTIPLE_REDUNDANCY_GROUPS_) allows *multiple active client connections* while preserving events when no client is
+connected. In this mode clients can be assigned to specific redundancy groups. The assignment is based on the IP address of the client.
+A redundancy group can have multiple simultaneous connections but only one of these connections can be active. The number of activated
+connections is restricted by the number of redundancy groups. Each redundancy group has a dedicated event queue.
+
+
+The server mode can be set with the _CS104_Slave_setServerMode_ function:
+
+  CS104_Slave_setServerMode(slave, CS104_MODE_MULTIPLE_REDUNDANCY_GROUPS);
+
+=== CS104: Defining multiple redundancy groups
+
+Redundancy groups only have to be created explicitly when using the servermode _CS104_MODE_MULTIPLE_REDUNDANCY_GROUPS_. You can assign multiple
+IP addresses to a redundancy group. Incoming connections from one of these IP addresses will then automatically be assigned to this specific
+redundancy group.
+
+When a redundancy group has no assigned IP address it works as a "catch all" group. This means that all incoming connections that
+are not assigned to one of the other groups will end up in this group.
+
+[[app-listing]]
+[source, c]
+.Example how to define multipe redundancy groups
+----
+CS104_Slave_setServerMode(slave, CS104_MODE_MULTIPLE_REDUNDANCY_GROUPS);
+
+CS104_RedundancyGroup redGroup1 = CS104_RedundancyGroup_create("red-group-1");
+CS104_RedundancyGroup_addAllowedClient(redGroup1, "192.168.2.9");
+
+CS104_RedundancyGroup redGroup2 = CS104_RedundancyGroup_create("red-group-2");
+CS104_RedundancyGroup_addAllowedClient(redGroup2, "192.168.2.223");
+CS104_RedundancyGroup_addAllowedClient(redGroup2, "192.168.2.222");
+
+CS104_RedundancyGroup redGroup3 = CS104_RedundancyGroup_create("catch-all");
+
+CS104_Slave_addRedundancyGroup(slave, redGroup1);
+CS104_Slave_addRedundancyGroup(slave, redGroup2);
+CS104_Slave_addRedundancyGroup(slave, redGroup3);
+----
+
 === CS101 (serial) slave configuration and setup
 
 Similar to the master side the CS101 slave side can also be configured for one of the two link layer modes (_balanced_ or _unbalanced_). A CS101 slave is represented by a _CS101_SLave_ object.