Cloud service providers ensure data security through a combination of measures, including encryption, identity and access management, and compliance with regulatory standards. They employ robust security protocols to protect data both at rest and in transit, mitigating risks associated with breaches and unauthorized access. Regular security audits and vulnerability assessments are conducted to identify weaknesses in their systems. Additionally, most providers offer customers advanced tools and features, such as firewalls, intrusion detection systems, and security information and event management (SIEM) solutions, to help safeguard their data. These practices are crucial in maintaining customer trust and meeting legal obligations.