What is RTT in CDN context?

RTT (Round-Trip Time) is the time it takes to send a request to a CDN server and receive a response. It is measured in milliseconds and indicates the network's response speed.

What is the difference between TTFB and RTT?

TTFB (Time To First Byte) measures the time from sending an HTTP request until receiving the first byte of the response. RTT measures the complete data exchange cycle at the network level. TTFB is usually greater than RTT because it includes the server's request processing time.

What Availability metric is considered good for CDN?

For professional CDN providers, an Availability (uptime) rate of 99.9% or higher is considered standard. Market leaders achieve 99.99% or even 99.999% availability.

Comparison of RTT for Russian CDN Providers

Which CDN has stable RTT nationwide?

Comparison CDNvideo EdgeCenter Curator Megafon MWS CDN

RTT TTFB Throughput Availability cached

not cached Conduct a test

Dynamics of average latency

Average latency
for period

What is RTT and why measure it?

RTT (Round Trip Time) — the time it takes for a data packet to travel from the user to the CDN node and back. Measured in milliseconds. The lower the RTT, the faster the browser establishes a connection with the server. High RTT is especially critical for:

websites with a high number of server requests
online gaming and video calls
any service where instant interface responsiveness matters

What do the RTT charts show?

Average RTT trend chart — allows you to track network stability. Sharp spikes indicate backbone channel congestion or issues at specific provider nodes.
Cities with high RTT — regions where the provider's CDN node is physically far from users, or where peering with local operators is not optimally configured.
Providers with high RTT — a comparative latency ranking. Helps quickly identify whose infrastructure is closest to your audience.