diff --git a/protocol_prototype/DryBox/Dockerfile b/protocol_prototype/DryBox/Dockerfile
new file mode 100644
index 0000000..1535ade
--- /dev/null
+++ b/protocol_prototype/DryBox/Dockerfile
@@ -0,0 +1,4 @@
+FROM python:3.9-slim
+WORKDIR /app
+COPY gsm_simulator.py /app
+CMD ["python", "gsm_simulator.py"]
diff --git a/protocol_prototype/DryBox/external_caller.py b/protocol_prototype/DryBox/external_caller.py
new file mode 100644
index 0000000..2b4655d
--- /dev/null
+++ b/protocol_prototype/DryBox/external_caller.py
@@ -0,0 +1,25 @@
+import socket
+
+import socket
+import time
+
+
+def connect():
+    caller_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    caller_socket.connect(('localhost', 5555))
+    caller_socket.send("CALLER".encode())
+    print("Connected to GSM simulator as CALLER")
+    time.sleep(2)  # Wait 2 seconds for receiver to connect
+
+    for i in range(5):
+        message = f"Audio packet {i + 1}"
+        caller_socket.send(message.encode())
+        print(f"Sent: {message}")
+        time.sleep(1)
+
+    caller_socket.send("CALL_END".encode())
+    print("Call ended.")
+    caller_socket.close()
+
+if __name__ == "__main__":
+    connect()
\ No newline at end of file
diff --git a/protocol_prototype/DryBox/external_receiver.py b/protocol_prototype/DryBox/external_receiver.py
new file mode 100644
index 0000000..b5c7fac
--- /dev/null
+++ b/protocol_prototype/DryBox/external_receiver.py
@@ -0,0 +1,36 @@
+import socket
+
+def connect():
+    receiver_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    receiver_socket.settimeout(15)  # Increase timeout to 15 seconds
+    receiver_socket.connect(('localhost', 5555))
+    receiver_socket.send("RECEIVER".encode())
+    print("Connected to GSM simulator as RECEIVER")
+
+    while True:
+        try:
+            data = receiver_socket.recv(1024).decode().strip()
+            if not data:
+                print("No data received. Connection closed.")
+                break
+            if data == "RINGING":
+                print("Incoming call... ringing")
+            elif data == "CALL_END":
+                print("Call ended by caller.")
+                break
+            elif data == "CALL_DROPPED":
+                print("Call dropped by network.")
+                break
+            else:
+                print(f"Received: {data}")
+        except socket.timeout:
+            print("Timed out waiting for data.")
+            break
+        except Exception as e:
+            print(f"Receiver error: {e}")
+            break
+
+    receiver_socket.close()
+
+if __name__ == "__main__":
+    connect()
\ No newline at end of file
diff --git a/protocol_prototype/DryBox/gsm_simulator.py b/protocol_prototype/DryBox/gsm_simulator.py
new file mode 100644
index 0000000..71dcf36
--- /dev/null
+++ b/protocol_prototype/DryBox/gsm_simulator.py
@@ -0,0 +1,94 @@
+import socket
+import threading
+import random
+import time
+
+class GSMSimulator:
+    def __init__(self, host='0.0.0.0', port=5555):
+        self.server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self.server_socket.bind((host, port))
+        self.server_socket.listen(2)
+        self.clients = {}
+        print("GSM Simulator started. Waiting for connections...")
+
+    def simulate_signal_strength(self):
+        return random.uniform(0, 1)
+
+    def handle_client(self, client_socket, address):
+        try:
+            client_socket.settimeout(5)
+            role = client_socket.recv(1024).decode().strip()
+            if role not in ["CALLER", "RECEIVER"]:
+                print(f"Invalid role received from {address}: {role}")
+                client_socket.close()
+                return
+            self.clients[role] = client_socket
+            print(f"{role} connected from {address}")
+
+            if role == "CALLER":
+                self.handle_caller(client_socket)
+            elif role == "RECEIVER":
+                self.handle_receiver(client_socket)
+        except Exception as e:
+            print(f"Error handling client {address}: {e}")
+        finally:
+            if role in self.clients:
+                del self.clients[role]
+            client_socket.close()
+
+    def handle_caller(self, caller_socket):
+        print("Caller connected, waiting for receiver...")
+        while "RECEIVER" not in self.clients:
+            time.sleep(1)
+        receiver_socket = self.clients["RECEIVER"]
+        print("Receiver found, sending RINGING...")
+        receiver_socket.send("RINGING".encode())
+
+        while True:
+            try:
+                data = caller_socket.recv(1024).decode().strip()
+                if not data:
+                    print("Caller disconnected unexpectedly.")
+                    receiver_socket.send("CALL_END".encode())
+                    break
+                if data == "CALL_END":
+                    print("Call terminated by caller.")
+                    receiver_socket.send("CALL_END".encode())
+                    break
+
+                signal = self.simulate_signal_strength()
+                if signal < 0.2:
+                    print("Call dropped due to low signal strength.")
+                    caller_socket.send("CALL_DROPPED".encode())
+                    receiver_socket.send("CALL_DROPPED".encode())
+                    break
+
+                print(f"Relaying to receiver: {data} (Signal: {signal:.2f})")
+                receiver_socket.send(data.encode())
+                time.sleep(0.1)  # Small delay to ensure data is sent properly
+            except Exception as e:
+                print(f"Error in caller loop: {e}")
+                receiver_socket.send("CALL_END".encode())
+                break
+
+    def handle_receiver(self, receiver_socket):
+        print("Receiver connected, waiting for data...")
+        try:
+            while True:
+                data = receiver_socket.recv(1024)
+                if not data:
+                    print("Receiver disconnected.")
+                    break
+        except Exception as e:
+            print(f"Error in receiver loop: {e}")
+
+    def run(self):
+        while True:
+            client_socket, address = self.server_socket.accept()
+            print(f"New connection from {address}")
+            thread = threading.Thread(target=self.handle_client, args=(client_socket, address))
+            thread.start()
+
+if __name__ == "__main__":
+    gsm = GSMSimulator()
+    gsm.run()
\ No newline at end of file
diff --git a/protocol_prototype/DryBox/launch_gsm_simulator.sh b/protocol_prototype/DryBox/launch_gsm_simulator.sh
new file mode 100755
index 0000000..99b0a72
--- /dev/null
+++ b/protocol_prototype/DryBox/launch_gsm_simulator.sh
@@ -0,0 +1,66 @@
+#!/bin/bash
+
+# Script to launch the GSM Simulator in Docker
+
+# Variables
+IMAGE_NAME="gsm-simulator"
+CONTAINER_NAME="gsm-sim"
+PORT="5555"
+
+# Check if Docker is installed
+if ! command -v docker &> /dev/null; then
+    echo "Error: Docker is not installed. Please install Docker and try again."
+    exit 1
+fi
+
+# Check if the gsm_simulator.py file exists in the current directory
+if [ ! -f "gsm_simulator.py" ]; then
+    echo "Error: gsm_simulator.py not found in the current directory."
+    echo "Please ensure gsm_simulator.py is present and try again."
+    exit 1
+fi
+
+# Create Dockerfile if it doesn't exist
+if [ ! -f "Dockerfile" ]; then
+    echo "Creating Dockerfile..."
+    cat <<EOF > Dockerfile
+FROM python:3.9-slim
+WORKDIR /app
+COPY gsm_simulator.py /app
+CMD ["python", "gsm_simulator.py"]
+EOF
+fi
+
+# Build the Docker image
+echo "Building Docker image: $IMAGE_NAME..."
+docker build -t $IMAGE_NAME .
+
+# Check if the build was successful
+if [ $? -ne 0 ]; then
+    echo "Error: Failed to build Docker image."
+    exit 1
+fi
+
+# Stop and remove any existing container with the same name
+if [ "$(docker ps -q -f name=$CONTAINER_NAME)" ]; then
+    echo "Stopping existing container: $CONTAINER_NAME..."
+    docker stop $CONTAINER_NAME
+fi
+if [ "$(docker ps -aq -f name=$CONTAINER_NAME)" ]; then
+    echo "Removing existing container: $CONTAINER_NAME..."
+    docker rm $CONTAINER_NAME
+fi
+
+# Run the Docker container
+echo "Launching GSM Simulator in Docker container: $CONTAINER_NAME..."
+docker run -d -p $PORT:$PORT --name $CONTAINER_NAME $IMAGE_NAME
+
+# Check if the container is running
+if [ $? -eq 0 ]; then
+    echo "GSM Simulator is running on port $PORT."
+    echo "Container ID: $(docker ps -q -f name=$CONTAINER_NAME)"
+    echo "You can now connect your external Python programs to localhost:$PORT."
+else
+    echo "Error: Failed to launch the container."
+    exit 1
+fi
\ No newline at end of file