- Added Doxygen source code documentation parts (donated by Fox-IT)
diff --git a/doxygen/input/doc_tcpip.h b/doxygen/input/doc_tcpip.h
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+/**
+ * @file
+ * TCP/IP communication module documentation file.
+ */
+
+/**
+ * @addtogroup tcpip_communication_module TCP/IP communication module
+ *
+ * The TCP/IP communication module provides for a channel of
+ * communication for the \link ssltls_communication_module SSL/TLS communication
+ * module\endlink to use.
+ * In the TCP/IP-model it provides for communication up to the Transport
+ * (or Host-to-host) layer.
+ * SSL/TLS resides on top of that, in the Application layer, and makes use of
+ * its basic provisions:
+ * - listening on a port (see \c net_bind()).
+ * - accepting a connection (through \c net_accept()).
+ * - read/write (through \c net_recv/\c net_send()).
+ * - close a connection (through \c net_close()).
+ *
+ * This way you have the means to, for example, implement and use an UDP or
+ * IPSec communication solution as a basis.
+ *
+ * This module can be used at server- and clientside to provide a basic
+ * means of communication over the internet.
+ */