An UDP server that listen to 100 ports and give response when those ports received any UDP packet.

UDP_servers.py

import socket
import select

if __name__ == "__main__":
    # constant of program
    IP_ADDRESS = "192.168.11.10"
    PORT_NO_START = 10024
    PORT_NO_END = 10124

    # the payload that UDP server will response
    PAYLOAD_STRING = f"I got your message\r\n"
    payload_ascii = PAYLOAD_STRING.encode("utf-8").hex()
    payload = bytes.fromhex(payload_ascii)

    # sockets that listen to ports 10024 until 10123, total of 100 ports
    udp_sockets = []
    for port in range(PORT_NO_START,PORT_NO_END):
        server_socket = socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
        server_socket.bind((IP_ADDRESS,port))
        udp_sockets.append(server_socket)
    
    # infinity loop to response to the incoming udp packet
    while True:
        readable, writable, exceptional = select.select(udp_sockets,[],[])
        for socket in readable:
            (client_data,(client_ip,client_port)) = socket.recvfrom(1024)
            # send out the response back to the request
            socket.sendto(payload,(client_ip,client_port))
            print(f"sent to {client_ip}:{client_port}")