Problem Description:

Design a Python-based system for remote command execution using socket programming. The system should allow a client to connect to a server and execute shell commands on the server machine remotely. Implement the following functionalities:

Requirements:

1. Server Operations:

• The server should be able to handle multiple client connections simultaneously.
• Display a list of connected clients.
• Accept commands from connected clients for remote execution.

2. Client Operations:

• Clients should be able to connect to the server.
• Clients can send shell commands to the server for execution.
• Receive and display the output/results of the executed command.

3. Command Protocol:

• Define a simple protocol for sending and receiving commands. Include information such as the command to execute, command parameters, and results.

4. User Interface:

• Implement a basic command-line or text-based user interface for clients to interact with the server and execute commands.

5. Security Measures:

• Implement basic security measures to authenticate clients and ensure secure communication.
• Ensure that clients can only execute predefined, safe commands on the server.

6. Error Handling:

• Implement error handling mechanisms to deal with scenarios like client disconnections and invalid commands.

7. Optional Enhancements:

• Allow clients to upload/download files to/from the server.