adding basic info

Author: usa-m

docs/usage/DdsServer.md

@@ -0,0 +1,65 @@
+# DdsServer
+
+DDS.Net.Server.**DdsServer** is the main entry-point of the library to execute the server for variables' exchange. Its constructor takes following parameters:
+
+```csharp
+DdsServer(
+    ServerConfiguration config,
+    VariablesConfiguration variablesConfig)
+```
+
+
+
+As a simple use-case, the server can be executed as:
+
+```csharp
+using DDS.Net.Server.Entities;
+using DDS.Net.Server.Interfaces;
+using DDS.Net.Server.Interfaces.DefaultLogger;
+using DDS.Net.Server.PublicExtensions;
+using DDS.Net.Server.PublicHelpers;
+
+namespace DDS.Net.Server.ConsoleApp
+{
+    internal class Program
+    {
+        private static ConsoleLogger logger =
+                  new ConsoleLogger(LogLevel.Information);
+        private static DdsServer server = null!;
+
+        static void Main(string[] args)
+        {
+            (bool isEnabled,
+             ServerConfiguration? config) =
+                ConfigurationProvider
+                    .GetServerConfiguration("config.ini", logger);
+
+            if (isEnabled && config != null)
+            {
+                server = new DdsServer(
+                    config,
+                    ConfigurationProvider
+                        .GetVariablesConfiguration(
+                            "vars-config.ini", logger));
+
+                server.Start();
+            }
+            else
+            {
+                server = null!;
+                logger.Error("Failed to start the server.");
+            }
+
+            ConsoleHelpers
+                .WaitForKey("Press ESC to exit.", ConsoleKey.Escape);
+
+            server?.Stop();
+        }
+    }
+}
+```
+
+
+
+
+