What is SLA (Serial Link Authentication/Authorization)?

SLA (Serial Link Authorization) is a Security feature that smartphone Manufacture Like Oppo, Vivo, Xiaomi Implement on their devices to Prevent unauthorized flashing. it is a process of verifying the identity of a device on a serial communication link to prevent unauthorized access or data interception.

Serial links are commonly used in various types of equipment, including smartphones, routers, switches, and firewalls, to establish communication between devices.

Authentication on a serial link is typically accomplished using a username and password, which are entered by the user before communication is established. The device on the other end of the link will verify the entered credentials against a local database of authorized users.

There are several authentication protocols that can be used to secure serial links, including:

  1. Password Authentication Protocol (PAP): This protocol sends the username and password in clear text across the link for verification.
  2. Challenge Handshake Authentication Protocol (CHAP): This protocol requires the device requesting authentication to send a challenge to the device on the other end of the link. The other device then responds with a hash of the challenge and a shared secret, which is compared to the expected result.
  3. Extensible Authentication Protocol (EAP): This protocol provides a framework for various authentication methods to be used, including digital certificates and smart cards.

Serial link authentication is an important security measure to prevent unauthorized access to sensitive data and protect against malicious attacks.