+ * jVCard remote uses a simple plain text protocol to
+ * transfer/retrieve/delete information from/to the server.
+ *
+ * <p>
+ *
+ * The protocol is based around <b>lines</b> of text and <b>blocks</b> of
+ * <b>lines</b>. The client sends <b>commands</b> while the server only
+ * answers with text data.
+ *
+ * <p>
+ *
+ * Some definitions:
+ * <ul>
+ * <li>A <b>line</b> is the text between two new-line characters (\n).
+ * <li>A <b>block</b> is all the <b>lines</b> between two end-of-block
+ * <b>lines</b>.
+ * <li>An end-of-block <b>line</b> is a special <b>line</b>
+ * containing only a dot (.).
+ * <li>A <b>command</b> is <b>block</b> whose first <b>line</b>
+ * contains the command in upper case text and an optional text
+ * argument, optionally followed by a second <b>block</b> of "input" data
+ * </ul>
+ *
+ * <p>
+ *
+ * Upon connection, the first thing that happen is that the server sends
+ * a VERSION <b>command</b> (a <b>block</b> whose first <b>line</b> is
+ * <b><tt>VERSION 1</tt></b>, possibly followed by some help text
+ * <b>lines</b>).
+ *
+ * <p>
+ *
+ * The client <b>MUST</b> answer with another VERSION <b>command</b>.
+ *
+ * <p>
+ *
+ * From that time on, the client is allowed to send <b>commands</b>
+ * as described by {@link be.nikiroo.jvcard.remote.Command}.
+ * If the client doesn't follow the rules in
+ * {@link be.nikiroo.jvcard.remote.Command}, the server will close
+ * the connection.