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diff --git a/examples/network/doc/src/secureudpclient.qdoc b/examples/network/doc/src/secureudpclient.qdoc
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--- a/examples/network/doc/src/secureudpclient.qdoc
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@@ -29,9 +29,96 @@
\example secureudpclient
\title DTLS client
\ingroup examples-network
- \brief Demonstrates how to implement a simple DTLS client
+ \brief This example demonstrates how to implement client-side DTLS connections.
- This example uses QUdpSocket, QDtlsClientVerifier, and QDtls to securely
- communicate over the User Datagram Protocol with DTLS servers.
+ \image secureudpclient-example.png Screenshot of the DTLS client example.
+
+ \note The DTLS client example is intended to be run alongside the \l{secureudpserver}{DTLS server} example.
+
+ The example DTLS client can establish several DTLS connections to one
+ or many DTLS servers. A client-side DTLS connection is implemented by the
+ DtlsAssociation class. This class uses QUdpSocket to read and write datagrams
+ and QDtls for encryption:
+
+ \snippet secureudpclient/association.h 0
+
+ The constructor sets the minimal TLS configuration for the new DTLS connection,
+ and sets the address and the port of the server:
+
+ \dots
+ \snippet secureudpclient/association.cpp 1
+ \dots
+
+ The QDtls::handshakeTimeout() signal is connected to the handleTimeout() slot
+ to deal with packet loss and retransmission during the handshake phase:
+
+ \dots
+ \snippet secureudpclient/association.cpp 2
+ \dots
+
+ To ensure we receive only the datagrams from the server, we connect our UDP socket to the server:
+
+ \dots
+ \snippet secureudpclient/association.cpp 3
+ \dots
+
+ The QUdpSocket::readyRead() signal is connected to the readyRead() slot:
+
+ \dots
+ \snippet secureudpclient/association.cpp 13
+ \dots
+
+ When a secure connection to a server is established, a DtlsAssociation object
+ will be sending short ping messages to the server, using a timer:
+
+ \snippet secureudpclient/association.cpp 4
+
+ startHandshake() starts a handshake with the server:
+
+ \snippet secureudpclient/association.cpp 5
+
+ The readyRead() slot reads a datagram sent by the server:
+
+ \snippet secureudpclient/association.cpp 6
+
+ If the handshake was already completed, this datagram is decrypted:
+
+ \snippet secureudpclient/association.cpp 7
+
+ otherwise, we try to continue the handshake:
+
+ \snippet secureudpclient/association.cpp 8
+
+ When the handshake has completed, we send our first ping message:
+
+ \snippet secureudpclient/association.cpp 9
+
+ The pskRequired() slot provides the Pre-Shared Key (PSK) needed during the handshake
+ phase:
+
+ \snippet secureudpclient/association.cpp 14
+
+ \note For the sake of brevity, the definition of pskRequired() is oversimplified.
+ The documentation for the QSslPreSharedKeyAuthenticator class explains in detail
+ how this slot can be properly implemented.
+
+ pingTimeout() sends an encrypted message to the server:
+
+ \snippet secureudpclient/association.cpp 10
+
+ During the handshake phase the client must handle possible timeouts, which
+ can happen due to packet loss. The handshakeTimeout() slot retransmits
+ the handshake messages:
+
+ \snippet secureudpclient/association.cpp 11
+
+ Before a client connection is destroyed, its DTLS connection must be shut down:
+
+ \snippet secureudpclient/association.cpp 12
+
+ Error messages, informational messages, and decrypted responses from servers
+ are displayed by the UI:
+
+ \snippet secureudpclient/mainwindow.cpp 0
*/