Update 103-token-authentication.md (#1734)

content/roadmaps/101-backend/content/109-apis/106-authentication/103-token-authentication.md

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 # Token authentication
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+Token-based authentication is a protocol which allows users to verify their identity, and in return receive a unique access token. During the life of the token, users then access the website or app that the token has been issued for, rather than having to re-enter credentials each time they go back to the same webpage, app, or any resource protected with that same token.
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+Auth tokens work like a stamped ticket. The user retains access as long as the token remains valid. Once the user logs out or quits an app, the token is invalidated.
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+Token-based authentication is different from traditional password-based or server-based authentication techniques. Tokens offer a second layer of security, and administrators have detailed control over each action and transaction.
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+But using tokens requires a bit of coding know-how. Most developers pick up the techniques quickly, but there is a learning curve.
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+<ResourceGroupTitle>Free Content</ResourceGroupTitle>
+<BadgeLink colorScheme='blue' badgeText='Read' href='https://www.okta.com/identity-101/what-is-token-based-authentication/'>What Is Token-Based Authentication?</BadgeLink>