google.com

DNS LOOKUP (google.com)

DNS LOOKUP (google.com)

DNS

google.com

DNS LOOKUP (google.com)

DNS LOOKUP (google.com)

DNS

google.com.        

108    IN    A 142.250.183.238

google.com

DNS LOOKUP (google.com)

DNS LOOKUP (google.com)

DNS

google.com.        

108    IN    A 142.250.183.238

UDP - User Data gram Protocol

UDP - User Data gram Protocol

  • DNS queries are small and fast - perfect for UDP.

  • UDP has no handshake, so it’s faster.

UDP - User Data gram Protocol

  • DNS queries are small and fast - perfect for UDP.

  • UDP has no handshake, so it’s faster.

But if the response is too large or truncated…

UDP - User Data gram Protocol

  • DNS queries are small and fast - perfect for UDP.

  • UDP has no handshake, so it’s faster.

But if the response is too large or truncated…

But if the response is too large or truncated…

DNS response > 512 bytes
→ Server replies: TC = 1 (Truncated)
→ Client retries using TCP

UDP for speed, TCP for reliability.

Server A

Server A

Razorpay Server

Server A

Razorpay Server

HTTP REQ

:POST /SERVER A

BODY PAYMENT SUCCESS

PAYMENT ID 1

Server A

Razorpay Server

HTTP REQ

:POST /SERVER A

BODY PAYMENT SUCCESS

PAYMENT ID 1

Webhook Call

deck

By piyushgargdev