diff --git a/.gradle/6.7/executionHistory/executionHistory.bin b/.gradle/6.7/executionHistory/executionHistory.bin
index 6747f8a14bb08ec1a50956ff041170aba4532049..4022146d1472f74863d73af392e749c34791b658 100644
Binary files a/.gradle/6.7/executionHistory/executionHistory.bin and b/.gradle/6.7/executionHistory/executionHistory.bin differ
diff --git a/.gradle/6.7/executionHistory/executionHistory.lock b/.gradle/6.7/executionHistory/executionHistory.lock
index 25fc1660df19a6424171748d9d04d149c1939b53..5fcbe37e3031cac971da54aa0c1dd0d2fede859d 100644
Binary files a/.gradle/6.7/executionHistory/executionHistory.lock and b/.gradle/6.7/executionHistory/executionHistory.lock differ
diff --git a/.gradle/6.7/fileHashes/fileHashes.bin b/.gradle/6.7/fileHashes/fileHashes.bin
index 9c1905f6c787641f693e99df291ebdf87adff2b2..d6cf0466a4a3b9f35de75acde663097f34b53831 100644
Binary files a/.gradle/6.7/fileHashes/fileHashes.bin and b/.gradle/6.7/fileHashes/fileHashes.bin differ
diff --git a/.gradle/6.7/fileHashes/fileHashes.lock b/.gradle/6.7/fileHashes/fileHashes.lock
index 73626d62011d0364eed1646de55c6b6a8c53d75a..79f4bc0edb3d5f5f6ada02ce288f6488f58d2c4b 100644
Binary files a/.gradle/6.7/fileHashes/fileHashes.lock and b/.gradle/6.7/fileHashes/fileHashes.lock differ
diff --git a/.gradle/6.7/javaCompile/classAnalysis.bin b/.gradle/6.7/javaCompile/classAnalysis.bin
new file mode 100644
index 0000000000000000000000000000000000000000..246622f520bbe8acea07ccc03c874e52016add99
Binary files /dev/null and b/.gradle/6.7/javaCompile/classAnalysis.bin differ
diff --git a/.gradle/6.7/javaCompile/javaCompile.lock b/.gradle/6.7/javaCompile/javaCompile.lock
index 35ba9bf0432ba916e33f6c5a856b4fc87dc462c6..c7fd346829fa54f9f9b295ae07ffef464e1f9929 100644
Binary files a/.gradle/6.7/javaCompile/javaCompile.lock and b/.gradle/6.7/javaCompile/javaCompile.lock differ
diff --git a/.gradle/6.7/javaCompile/taskHistory.bin b/.gradle/6.7/javaCompile/taskHistory.bin
index 370e64289da699237ab29d76541262222e7e3cdc..c01f98b8788c92aee488d8d9a90a0cb1109ff43f 100644
Binary files a/.gradle/6.7/javaCompile/taskHistory.bin and b/.gradle/6.7/javaCompile/taskHistory.bin differ
diff --git a/.gradle/buildOutputCleanup/buildOutputCleanup.lock b/.gradle/buildOutputCleanup/buildOutputCleanup.lock
index be5109cf65a07c66599f2fc5db4bce04f2904bdf..48a14f2ce8fd5fb4b498260d612c6160d4ccdff0 100644
Binary files a/.gradle/buildOutputCleanup/buildOutputCleanup.lock and b/.gradle/buildOutputCleanup/buildOutputCleanup.lock differ
diff --git a/.gradle/buildOutputCleanup/outputFiles.bin b/.gradle/buildOutputCleanup/outputFiles.bin
index f205b0ddfe9c49ccd03b257269eef4658d48a994..1850a06e517c8d48f18c73dc9a80cc61f40cd324 100644
Binary files a/.gradle/buildOutputCleanup/outputFiles.bin and b/.gradle/buildOutputCleanup/outputFiles.bin differ
diff --git a/.idea/.name b/.idea/.name
new file mode 100644
index 0000000000000000000000000000000000000000..433ed8ab65bd7dcf8bbfc2d09467c342b0c055fc
--- /dev/null
+++ b/.idea/.name
@@ -0,0 +1 @@
+setup_SDP
\ No newline at end of file
diff --git a/.idea/gradle.xml b/.idea/gradle.xml
index ba1ec5c7e20c12eb5b893684698eab151c4a8803..611e7c8ad7b91e576987485e8678b0fdad4193ae 100644
--- a/.idea/gradle.xml
+++ b/.idea/gradle.xml
@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
+  <component name="GradleMigrationSettings" migrationVersion="1" />
   <component name="GradleSettings">
     <option name="linkedExternalProjectsSettings">
       <GradleProjectSettings>
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 0000000000000000000000000000000000000000..35eb1ddfbbc029bcab630581847471d7f238ec53
--- /dev/null
+++ b/.idea/vcs.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/build/classes/java/main/TCPClient.class b/build/classes/java/main/TCPClient.class
deleted file mode 100644
index fb2030595ea89798deb9a5b050a65942ae1102c2..0000000000000000000000000000000000000000
Binary files a/build/classes/java/main/TCPClient.class and /dev/null differ
diff --git a/build/classes/java/main/TCPServer.class b/build/classes/java/main/TCPServer.class
deleted file mode 100644
index f81e36253e1100b775bf383b87e96b8eb2055fda..0000000000000000000000000000000000000000
Binary files a/build/classes/java/main/TCPServer.class and /dev/null differ
diff --git a/build/classes/java/main/iterative/Client.class b/build/classes/java/main/iterative/Client.class
new file mode 100644
index 0000000000000000000000000000000000000000..4a61020a212f802f582fd9c3b955c937c146f7b5
Binary files /dev/null and b/build/classes/java/main/iterative/Client.class differ
diff --git a/build/classes/java/main/iterative/IterativeServer.class b/build/classes/java/main/iterative/IterativeServer.class
new file mode 100644
index 0000000000000000000000000000000000000000..57adf30ba1c481adf952ff0828dcef4f72bbbcc8
Binary files /dev/null and b/build/classes/java/main/iterative/IterativeServer.class differ
diff --git a/build/classes/java/main/multithread/MultiServer.class b/build/classes/java/main/multithread/MultiServer.class
new file mode 100644
index 0000000000000000000000000000000000000000..6f33462f7cf9aca695339023b0e255fc6c2cfcdc
Binary files /dev/null and b/build/classes/java/main/multithread/MultiServer.class differ
diff --git a/build/classes/java/main/multithread/ServerThread.class b/build/classes/java/main/multithread/ServerThread.class
new file mode 100644
index 0000000000000000000000000000000000000000..16b06dd85beca25fe594f7e739d1f829b88fde71
Binary files /dev/null and b/build/classes/java/main/multithread/ServerThread.class differ
diff --git a/build/tmp/compileJava/source-classes-mapping.txt b/build/tmp/compileJava/source-classes-mapping.txt
index a96fe92536f9f2604a5df3bc41c40bb8c40e00ce..c141fafdfbeab00a76cebaa5a40c52d1ed2c2800 100644
--- a/build/tmp/compileJava/source-classes-mapping.txt
+++ b/build/tmp/compileJava/source-classes-mapping.txt
@@ -1,4 +1,8 @@
-TCPServer.java
- TCPServer
-TCPClient.java
- TCPClient
+iterative/Client.java
+ iterative.Client
+iterative/IterativeServer.java
+ iterative.IterativeServer
+multithread/MultiServer.java
+ multithread.MultiServer
+multithread/ServerThread.java
+ multithread.ServerThread
diff --git a/src/main/java/TCPClient.java b/src/main/java/TCPClient.java
deleted file mode 100644
index c6441695de2e538012832b82986c3cda818f1d3b..0000000000000000000000000000000000000000
--- a/src/main/java/TCPClient.java
+++ /dev/null
@@ -1,38 +0,0 @@
-import java.io.*; 
-import java.net.*;
-
-class TCPClient { 
-	public static void main(String argv[]) throws Exception { 
-		String sentence; 
-		String modifiedSentence; 
-
-		/* Inizializza l'input stream (da tastiera) */
-		BufferedReader inFromUser = 
-			new BufferedReader(new InputStreamReader(System.in)); 
-
-		/* Inizializza una socket client, connessa al server */
-		Socket clientSocket = new Socket("localhost", 6789); 
-
-		/* Inizializza lo stream di output verso la socket */
-		DataOutputStream outToServer = 
-			new DataOutputStream(clientSocket.getOutputStream()); 
-
-		/* Inizializza lo stream di input dalla socket */
-		BufferedReader inFromServer = 
-			new BufferedReader(new
-					InputStreamReader(clientSocket.getInputStream())); 
-
-		/* Legge una linea da tastiera */
-		sentence = inFromUser.readLine(); 
-
-		/* Invia la linea al server */
-		outToServer.writeBytes(sentence + '\n'); 
-
-		/* Legge la risposta inviata dal server (linea terminata da \n) */
-		modifiedSentence = inFromServer.readLine(); 
-
-		System.out.println("FROM SERVER: " + modifiedSentence); 
-
-		clientSocket.close(); 
-	}
-}
diff --git a/src/main/java/TCPServer.java b/src/main/java/TCPServer.java
deleted file mode 100644
index 5e565ede1f704aee1d32ed2898de03a15bfaec93..0000000000000000000000000000000000000000
--- a/src/main/java/TCPServer.java
+++ /dev/null
@@ -1,43 +0,0 @@
-import java.io.*; 
-import java.net.*; 
-
-class TCPServer { 
-
-	public static void main(String argv[]) throws Exception 
-	{ 
-		String clientSentence; 
-		String capitalizedSentence; 
-
-		/* Crea una "listening socket" sulla porta specificata */
-		ServerSocket welcomeSocket = new ServerSocket(6789); 
-
-		while(true) { 
-			/* 
-			 * Viene chiamata accept (bloccante). 
-			 * All'arrivo di una nuova connessione crea una nuova
-			 * "established socket"
-			 */
-			Socket connectionSocket = welcomeSocket.accept(); 
-
-			/* Inizializza lo stream di input dalla socket */
-			BufferedReader inFromClient = 
-				new BufferedReader(new
-						InputStreamReader(connectionSocket.getInputStream())); 
-
-			/* Inizializza lo stream di output verso la socket */
-			DataOutputStream  outToClient = 
-				new DataOutputStream(connectionSocket.getOutputStream()); 
-
-			/* Legge una linea (terminata da \n) dal client */
-			clientSentence = inFromClient.readLine(); 
-
-			capitalizedSentence = clientSentence.toUpperCase() + '\n'; 
-
-			/* Invia la risposta al client */
-			outToClient.writeBytes(capitalizedSentence);
-
-			connectionSocket.close();
-
-		}
-	}
-}
diff --git a/src/main/java/iterative/Client.java b/src/main/java/iterative/Client.java
new file mode 100644
index 0000000000000000000000000000000000000000..d5f4ea4d7f74f1d395b7e34f4f628f4b8564b844
--- /dev/null
+++ b/src/main/java/iterative/Client.java
@@ -0,0 +1,40 @@
+package iterative;
+
+import java.io.*;
+import java.net.*;
+
+class Client {
+    public static void main(String argv[]) throws Exception {
+        String sentence;
+        String modifiedSentence;
+
+        // input stream initialization (from user keyboard)
+        BufferedReader inFromUser =
+                new BufferedReader(new InputStreamReader(System.in));
+
+		/* client socket initialization
+			localhost: server address
+			6789: server service port number */
+        Socket clientSocket = new Socket("localhost", 6789);
+
+        // output stream towards socket initialization
+        DataOutputStream outToServer =
+                new DataOutputStream(clientSocket.getOutputStream());
+
+        // input stream from socket initialization
+        BufferedReader inFromServer =
+                new BufferedReader(
+                        new InputStreamReader(clientSocket.getInputStream()));
+
+        // read a line from the user
+        sentence = inFromUser.readLine();
+
+        // send the line to the server
+        outToServer.writeBytes(sentence + '\n');
+
+        // read the response from the server
+        modifiedSentence = inFromServer.readLine();
+        System.out.println("FROM SERVER: " + modifiedSentence);
+        clientSocket.close();
+    }
+}
diff --git a/src/main/java/iterative/IterativeServer.java b/src/main/java/iterative/IterativeServer.java
new file mode 100644
index 0000000000000000000000000000000000000000..afddbb92902ed36ac4367ad1775961277b463f52
--- /dev/null
+++ b/src/main/java/iterative/IterativeServer.java
@@ -0,0 +1,41 @@
+package iterative;
+
+import java.io.*;
+import java.net.*;
+
+class IterativeServer {
+    public static void main(String argv[]) throws Exception {
+        String clientSentence;
+        String capitalizedSentence;
+
+        // create a "listening socket" on the specified port
+        ServerSocket welcomeSocket = new ServerSocket(6789);
+
+        while(true) {
+			/*	accept is a blocking call
+				once a new connection arrived, it creates
+				a new "established socket"	*/
+            Socket connectionSocket = welcomeSocket.accept();
+
+            // input stream from the socket initialization
+            BufferedReader inFromClient =
+                    new BufferedReader(
+                            new InputStreamReader(connectionSocket.getInputStream()));
+
+            // output stream to the socket initialization
+            DataOutputStream outToClient =
+                    new DataOutputStream(connectionSocket.getOutputStream());
+
+            // read a line (that terminates with \n) from the client
+            clientSentence = inFromClient.readLine();
+
+            // wait for 10 seconds
+            //Thread.sleep(10000);
+
+            capitalizedSentence = clientSentence.toUpperCase() + '\n';
+
+            // send the response to the client
+            outToClient.writeBytes(capitalizedSentence);
+        }
+    }
+}
diff --git a/src/main/java/multithread/MultiServer.java b/src/main/java/multithread/MultiServer.java
new file mode 100644
index 0000000000000000000000000000000000000000..3de0e3fc1a41a59fba98718f00dab204980581d7
--- /dev/null
+++ b/src/main/java/multithread/MultiServer.java
@@ -0,0 +1,21 @@
+package multithread;
+
+import java.io.*;
+import java.net.*;
+
+class MultiServer {
+    public static void main(String argv[]) throws Exception {
+        ServerSocket welcomeSocket = new ServerSocket(6789);
+
+        while(true) {
+            Socket connectionSocket = welcomeSocket.accept();
+
+            // thread creation passing the established socket as arg
+            ServerThread theThread =
+                    new ServerThread(connectionSocket);
+
+            // start of the thread
+            theThread.start();
+        }
+    }
+}
diff --git a/src/main/java/multithread/ServerThread.java b/src/main/java/multithread/ServerThread.java
new file mode 100644
index 0000000000000000000000000000000000000000..d0806d2c9dc5ac40a1be79c10fda67bbec9cd3ee
--- /dev/null
+++ b/src/main/java/multithread/ServerThread.java
@@ -0,0 +1,37 @@
+package multithread;
+
+import java.io.*;
+import java.net.*;
+
+public class ServerThread extends Thread {
+    private Socket connectionSocket = null;
+    private BufferedReader inFromClient;
+    private DataOutputStream outToClient;
+
+    // the constructor argument is an established socket
+    public ServerThread(Socket s) {
+        connectionSocket = s;
+        try {
+            inFromClient =
+                    new BufferedReader(
+                            new InputStreamReader(connectionSocket.getInputStream()));
+            outToClient =
+                    new DataOutputStream(connectionSocket.getOutputStream());
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+
+    public void run() {
+        String clientSentence;
+        String capitalizedSentence;
+        try {
+            clientSentence = inFromClient.readLine();
+            capitalizedSentence = clientSentence.toUpperCase() + '\n';
+            outToClient.writeBytes(capitalizedSentence);
+            connectionSocket.close();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+}