RTT-0 (Zero Round-Trip Time)
0-RTT (Zero Round-Trip Time Resumption) is a high-performance feature of modern network protocols like TLS 1.3 and HTTP/3. It allows a browser that has recently connected to a server to send application data in its very first message on a subsequent visit, without waiting for the security handshake to complete. This effectively eliminates one full Round Trip Time (RTT) from the connection setup, significantly speeding up the Time To First Byte (TTFB), especially on mobile networks.
Related web performance terms
- ROI (Return on Investment)
ROI is a business metric used to evaluate the profitability of an investment by comparing the net profit to the cost of the investment. It is typically expressed as a percentage.
- RTT (Round Trip Time)
RTT stands for Round Trip Time and is a fundamental networking metric. It measures the total time it takes for a data packet to travel from a source (like a user's browser) to a destination (a serv…
- Real User Monitoring (RUM)
See Field Data.
- Redirect Time
A redirect is a response from a server that automatically forwards a user from one URL to another. While sometimes necessary (e.g., for tracking or moving content), redirects are very harmful to performance.