For secure data transmission in e-commerce, technologies such as SSL/TLS (Secure Sockets Layer/Transport Layer Security) are commonly used. These protocols encrypt data exchanged between a user's browser and a web server, protecting sensitive information like credit card numbers and personal details. Additional measures may include using firewalls, VPNs (Virtual Private Networks), and secure payment gateways to enhance security. Implementing these technologies helps build trust with consumers and ensures compliance with data protection regulations.