Peer-to-Peer Shopping System

This project implements a Peer-to-Peer (P2P) Shopping System that allows users to buy and sell items through a server-mediated communication model. The system uses UDP for general communication and TCP for secure transactions, ensuring the safety and efficiency of peer interactions.

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Features

• Registration and Deregistration: Peers can register with the server to participate in the system and deregister when done.
• Item Searching and Offering: Buyers can search for items, and sellers can offer items with a specified price.
• Secure Transactions: Sensitive buyer-seller information is transmitted securely via TCP.
• Dynamic Negotiation: The server facilitates price negotiations between buyers and sellers if no offer matches the buyer's maximum price.
• Persistent State: Both server and peers persist their state to handle restarts without data loss.
• Logging: Comprehensive logging of activities for debugging and tracking purposes.

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Technologies Used

• Programming Language: Python
• Networking: UDP and TCP sockets
• Data Persistence: JSON-based storage for peer inventory and server state
• Threading: Multithreaded architecture for concurrent request handling
• Logging: Centralized logging for peers and server

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How It Works

System Overview

1. Registration: A peer registers with the server using its unique name and socket details.
2. Item Search: Buyers send item search requests to the server, which forwards the search to all registered sellers.
3. Offers: Sellers respond with offers if the item is available in their inventory.
4. Negotiation: If no valid offers match, the server negotiates with the seller offering the lowest price.
5. Transaction Finalization: Once a buyer accepts an offer, TCP connections handle sensitive data exchange (e.g., credit card details and shipping addresses).

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Installation

Prerequisites

• Python 3.6 or higher installed on your system.

Steps

1. Clone the repository:

   git clone https://github.com/rishit2003/Peer-to-Peer-Shopping-System.git
   cd Peer-to-Peer-Shopping-System

2. Install dependencies (if any).

3. Run the server:

   python server.py

4. Run a peer client:

   python peer.py

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Usage

1. Start the Server:

   • Run server.py and enter the desired UDP port when prompted.

2. Start a Peer:

   • Run peer.py for each peer and provide the server IP, server UDP port, peer name, and peer's UDP and TCP ports.

3. Interactive Menu:

   • The peer provides options to register, deregister, search for items, add inventory items, and exit.

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Project Structure

Peer Side

Peer-to-Peer-Shopping-System/
│
├── peer.py                 # Main script for peer operations
├── <peer_name>_inventory.json  # Inventory storage for each peer
├── <peer_name>.log         # Peer log file
└── README.md               # Project documentation

Server Side

Peer-to-Peer-Shopping-System/
│
├── server.py               # Main script for server operation
├── server.json             # Persistent state storage for the server
├── server.log              # Server log file
└── README.md               # Project documentation

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Example Workflow

1. Register a Peer:
   Peer1 sends a REGISTER request to the server.

2. Search for an Item:
   Peer1 sends a LOOKING_FOR request for an item (e.g., "Laptop").

3. Receive Offers:
   Sellers respond with OFFER messages if the item is available.

4. Transaction Finalization:
   Upon acceptance, a TCP connection handles secure credit card and shipping details.

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Screenshots

• Server Startup
  

• Peer Registration
  

• Item Search & Transaction Finalization

  • Peer1:
  
  • Peer2:
  

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Logging

• Server Logs: Logs server operations, requests, and state updates in server.log.
• Peer Logs: Each peer logs its activities (e.g., sent messages, inventory updates) in <peer_name>.log.

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Future Enhancements

• Add a GUI for easier interaction.
• Implement user authentication for additional security.
• Optimize message handling for scalability.

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Contributors

• Rishit Mittal (rishit2003)
• Rayan Alkayal (Rayan99k)
• Mohammad Natsheh (Mordred311)

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