Tokens are the digital credentials that represent the identity of a user and system. They are used to grant access to resources or services in an application and play a crucial role in authentication and authorization techniques. There are different types of tokens, each serving a specific purpose. But today we are here to discuss the two most common tokens access token and refresh token.
Access Tokens: Opening the Gateway to Resources
An access token is like a digital key that grants permission to a client application to access specific resources on behalf of a user. These resources could be anything from user data to services protected by an API. The process begins with the user granting consent to the client application, which then requests an access token from the authorization server.
Key Characteristics of Access Tokens:
Purpose: The primary purpose of an access token is to provide secure access to protected resources.
Usage: Once obtained, the client includes the access token in its requests to the resource server. The server validates the token, ensuring the client has the necessary permissions, and then serves the requested resource.
Lifespan: Access tokens have a relatively short lifespan, promoting security by limiting the time during which a compromised token can be misused.
Security: As a bearer token, the access token must be handled securely by the client, as possession of the token alone grants access.
You can create an access token using jwt.sign() method which takes three argument
The payload fancy name for data
The API secret key
An object that contains the expiry of the access token
jwt.sign(
{
_id: this._id,
},
process.env.ACCESS_TOKEN_SECRET, // Secret key defined in environment file
{
expiresIn: process.env.ACCESS_TOKEN_EXPIRY, // Expiry time defined in env file
}
)
Refresh Tokens: Maintaining Access Without the Need for Reauthentication
Like an access token, a refresh token is also a digital key but it serves a different purpose, while access tokens last for a short time, refresh tokens provide a means to obtain fresh access tokens without requiring the user to re-enter their credentials. Refresh tokens are issued alongside access tokens during the initial authentication and authorization process.
Key Characteristics of Refresh Tokens:
Purpose: The primary purpose of a refresh token is to obtain a new access token without user involvement.
Usage: When the access token expires, the client uses the refresh token to request a new access token. This process occurs without user interaction, providing a seamless experience.
Lifespan: Refresh tokens have a longer lifespan compared to access tokens. They are designed to be valid for an extended period, reducing the frequency of user authentication.
Security: Refresh tokens are securely stored by the client and are not meant to be shared with the resource server. Their prolonged validity enhances security by minimizing the exposure of user credentials.
The procedure of creating a refresh token is the same as an access token but the difference between them is that they both serve different purposes.
To create a refresh token you again use the jwt.sign() method with three arguments:
jwt.sign(
{
_id: this._id,
},
process.env.REFRESH_TOKEN_SECRET, // Secret key defined in environment file
{
expiresIn: process.env.REFRESH_TOKEN_EXPIRY, // Expiry time defined in env file
}
)
Conclusion:
In conclusion, access tokens and refresh tokens are integral components of modern web applications, working together to provide a robust and user-friendly authentication and authorization mechanism. Understanding the distinct roles they play is crucial for developers, ensuring the implementation of secure and efficient authentication workflows.
For more information watch the video: Access token and refresh token by Hitesh Choudhary on YouTube.