Follow these guidelines to ensure secure, reliable, and compliant integration with our SMS API. This comprehensive guide covers everything from security to compliance for production-ready implementations.

1. Always Use HTTPS and POST for All Requests

Why:
HTTPS encrypts data in transit, protecting against eavesdropping, tampering, and man-in-the-middle attacks. Using the POST method ensures that sensitive data (like credentials) is passed in the request body rather than the URL, where it could be logged or cached in plaintext.

What to do:

  • Use https:// for all API endpoints
  • Send all requests via HTTP POST
  • Never include credentials in the URL query string
❌ Don't do this: 
https://api.smsprovider.com/send/?username=USER&password=PASS
✅ Do this: 
curl -X POST https://api.smsprovider.com/send/ \
  -H "Content-Type: application/json" \
  -d '{"username": "USER", "password": "PASS", ...}'

2. Never Hardcode Credentials in Your Source Code

Why:
Hardcoded credentials are a security risk, difficult to change, and can be exposed in version control. They also prevent users from updating passwords without code changes.

What to do:

  • Store credentials in environment variables, config files, or a secure secrets management service
  • Ensure your app allows password updates without redeployment

3. Validate and Sanitize All Inputs

Mobile Numbers

  • Ensure numbers are in international format (e.g., 96512345678 for Kuwait)
  • Remove leading + or 00 before the country code
  • Accept only English numerals (0–9). Arabic or Hindi digits will be rejected
  • Validate length and structure per country before sending

Message Content

  • Remove unsupported emojis, special characters, or non-UTF-8 characters unless explicitly allowed
  • For Arabic or Unicode content, ensure proper encoding (UTF-8) and test before delivery

4. Test Messages in Both English and Arabic Before Deployment

Why:
Encoding issues can cause messages to appear as gibberish. Testing both languages ensures your encoding and character handling work correctly.

What to do:

  • Send test messages in English and Arabic during development
  • Verify delivery and readability on actual devices

5. Follow OTP (One-Time Password) Best Practices

Use a Transactional Private Sender ID

For faster and more reliable OTP delivery, always use a dedicated transactional sender ID instead of a promotional or test sender ID.

Include Your App/Company Name

To comply with telecom regulations and improve trust, include your application or company name in OTP messages.

✅ Example:
Your verification code for MyApp is 123456.

Set a Sensible Resend Time Window

  • Allow at least 3–4 minutes before permitting an OTP resend
  • This gives users time to receive, locate, and enter the code
  • Align with common practices (e.g., KNET uses 4-minute expiration)

6. Prevent Automation and Abuse

Use CAPTCHA or Similar Mechanisms

Add CAPTCHA or silent bot detection to OTP request and sign-up forms to prevent automated attacks.

Implement Rate Limiting

  • Limit OTP requests per phone number per hour (e.g., max 3–5 attempts)
  • Restrict sign-ups or SMS sends by IP address over a rolling window
  • This protects your balance from drainage and prevents service abuse

7. Optimize API Usage

Avoid Unnecessary API Calls for Balance

After a successful send, the API response already includes:

  • Points deducted for the message
  • Remaining balance

There's no need to call the /balance/ endpoint after each send. Use the built-in low-balance notifications for your account instead.

Handle API Responses and Errors

  • Implement proper error handling for HTTP status codes and API-level errors (e.g., insufficient balance, invalid number, content rejection)
  • Log errors for debugging but avoid exposing sensitive details in client-facing messages

8. Ensure Compliance and Security

Log Securely

Avoid logging full API requests or responses that contain credentials, phone numbers, or message content. If logging is necessary, mask sensitive data.

Keep SDKs and Libraries Updated

If you're using an official SDK, keep it updated to benefit from security patches and performance improvements.

Review Telecom Regulations

Stay informed about local telecom rules regarding sender IDs, message content, and user consent, especially for promotional messages.

9. Monitor and Alert

  • Set up alerts for failed sends, sudden increases in errors, or balance thresholds
  • Monitor delivery rates and latency to detect issues early

10. Testing Strategy

Testing checklist:

  • Unit tests for phone number validation and sanitization
  • Integration tests with the SMS API (using test credentials)
  • Test with various character sets (English, Arabic, special characters)
  • Test with invalid inputs (malformed numbers, empty messages)
  • Test rate limiting and bot prevention mechanisms
  • Verify OTP expiration and resend functionality
  • Test error scenarios (network failures, invalid credentials)

Summary Checklist Before Going Live

By following these practices, you'll build a more secure, reliable, and user-friendly SMS integration. For further details, refer to our official API documentation or contact support.