Most APIs fail under fake traffic — here’s how big companies stay online during DDoS attacks.

1️⃣ Rate Limit Requests Per IP / API Key
👉 Limit how many calls each client can send, so bots can’t flood you.
Example: Like allowing only 5 people per minute at an ATM so one person can’t block everyone.

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2️⃣ Block Bad Traffic at the Network Edge
👉 Drop malicious IPs before they reach your servers.
Example: Like stopping unwanted visitors at the main gate instead of your front door.

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3️⃣ CDN Absorbs the Attack
👉 Use Cloudflare/Akamai/AWS CloudFront to handle huge spikes globally.
Example: Instead of one shop facing 1M customers, the load spreads across 1,000 branches.

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4️⃣ Web Application Firewall (WAF)
👉 Automatically blocks bots, SQL injection attempts, weird headers, etc.
Example: Like a security guard rejecting anyone with fake IDs or suspicious behavior.

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5️⃣ Challenge Suspicious Traffic (CAPTCHA / JS Challenge)
👉 Force bots to prove they’re real.
Example: Like asking someone for an OTP before letting them into your apartment.

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6️⃣ Autoscale Under Heavy Load
👉 Add more servers when traffic spikes to avoid total collapse.
Example: Like opening extra billing counters when a crowd suddenly forms.

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7️⃣ Geo-Blocking / IP Reputation Filtering
👉 Block or throttle regions where attacks originate.
Example: Like closing one side of a shop entrance when a huge crowd suddenly appears.

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