OAuth 2.0

Industry-standard authorization framework for secure API access

⬢ স্তর 2প্রযুক্তিগত

উচ্চ

বেতনের প্রভাব

3 মাস

শেখার সময়

মাঝারি

কঠিনতা

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ক্যারিয়ার

এক নজরে

OAuth 2.0 is the authorization protocol powering 'Sign in with Google/GitHub/Facebook' and securing API integrations across the web. Career path: Implementation Engineer (Auth Code flow, PKCE, social login, $105-135k) → Specialist (token management, OIDC, multi-tenant auth, refresh token rotation, $135-170k) → Architect (identity provider design, token introspection, custom grant types, security threat modeling, $170-220k+) over 3-4 months. Salary premium: $15k-$30k above base. Tools: Auth0, Okta, Keycloak, AWS Cognito, Azure AD, Firebase Auth, Supabase Auth, Clerk, NextAuth.js, jwt.io. Competes with SAML 2.0 (enterprise, heavier) and custom session tokens (less secure, more maintenance).

OAuth 2.0 কী

OAuth 2.0 is the industry-standard authorization framework for secure, delegated API access and authentication across the web. It powers "Sign in with Google/GitHub/Facebook," enables third-party integrations (Stripe, Slack, Gmail API), and secures API-to-API communication. OAuth separates authentication (proving identity) from authorization (granting permissions), enabling secure access without sharing passwords. Career progression: Implementation Engineer (Auth Code flow, PKCE, social login, $105-135k) → Specialist (token management, OIDC, multi-tenant auth, refresh token rotation, $135-170k) → Architect (identity provider design, token introspection, custom grant types, security threat modeling, $170-220k+) over 3-4 months. OAuth 2.0 is 15+ years old but still evolving: OAuth 2.1 simplifies the spec, fine-grained authorization (RAR) adds precision, and passkeys are reducing password dependency. In 2026, OAuth + OIDC is the foundation of every authentication system. Understanding OAuth deeply is non-negotiable for backend/fullstack engineers, payment processors, and any platform handling user login or API access.

🔧 সরঞ্জাম এবং ইকোসিস্টেম

Auth0OktaKeycloakAWS CognitoAzure ADFirebase AuthSupabase AuthClerkNextAuth.jsjwt.ioPassport.jsory/hydra

📋 শুরু করার আগে

Backend Development Apis Rest Design Cybersecurity

💰 অঞ্চল অনুযায়ী বেতন

অঞ্চল	জুনিয়র	মধ্য	সিনিয়র
USA	$105k	$145k	$190k
UK	£65k	£90k	£130k
EU	€70k	€95k	€140k
CANADA	C$110k	C$155k	C$210k

🎓 সার্টিফিকেশন

Auth0 Certified Associate Okta Certified Professional OpenID Certified Professional

⚖ এর সাথে তুলনা করুন

Cybersecurity Apis Rest Design Backend Development

❓ প্রায়শই জিজ্ঞাসিত প্রশ্ন

OAuth 2.0 vs OpenID Connect, what's the difference?

OAuth 2.0 = authorization (grants access to resources). OpenID Connect = authentication (proves who you are). Use OAuth for 'access your Google Drive' and OIDC for 'sign in with your Google account'. OIDC is built on top of OAuth 2.0, adding an ID token with user info. Modern practice: always use OIDC when you need both auth and access.

Authorization Code flow vs Implicit flow, which should I use?

Authorization Code: secure, use for web apps and mobile apps (with PKCE). Tokens never exposed in browser. Implicit: deprecated, use only for legacy SPAs without a backend. Always add PKCE to Authorization Code flow for public clients (SPAs, mobile).

What is PKCE and why is it essential?

PKCE (Proof Key for Code Exchange) prevents authorization code interception attacks. Generate a random code_verifier (43-128 chars), hash it to code_challenge, send in auth request, verify on token exchange. Mandatory for SPAs and mobile apps. Use in Authorization Code flow. Without PKCE: attacker intercepts auth code and trades it for tokens.

How do I securely store and refresh tokens?

Access tokens: store in httpOnly cookies (not localStorage, vulnerable to XSS). Refresh tokens: httpOnly cookie, rotate on each use, short-lived (15 min access token, 7-30 day refresh). Implement token revocation on logout. Server-side validation: never trust tokens without verifying signature and expiry.

JWT validation, what must I check?

Verify signature using the provider's public key (JWKS endpoint). Check expiry (exp claim). Validate issuer (iss). Check audience (aud) matches your app. Never skip signature validation. Use jwt.io to decode and inspect tokens during development.

How do I implement social login (Google, GitHub)?

Register your app with the provider (get Client ID and Secret). Redirect user to their authorization endpoint. User grants permission and gets redirected back with an authorization code. Exchange code for access token. Fetch user info from provider's API. Create or update local user. Return session token to client.

What's the difference between access tokens and refresh tokens?

Access token: short-lived (15 min), grants API access, included in every request. Refresh token: long-lived (days/weeks), used to get new access token, stored securely, never sent in API requests. Refresh flow: client sends refresh token, server validates and returns new access token. If refresh token compromised, attacker gets limited access until it expires.