{cid}.{gateway_domain}`). This means that the retrieval performance for some gateways includes round-trips to resolve redirects. Subdomain gateways are generally more secure because of improved origin isolation at the expense of additional round-trips to resolve to the subdomain.

The data is segmented along the dimensions: region, cache status, and CID source.

Region

We have deployed our Tiros measurement suite in different AWS regions around the world. They correspond to the following region identifiers:

`eu-central-1`: Europe (Frankfurt)

`us-east-2`: US East (Ohio)

`us-west-1`: US West (N. California)

`ap-southeast-2`: Asia Pacific (Sydney)

Cache Status

Each time Tiros probes an HTTP gateway, it sends two requests for the same CID one after another. With the first request we attempt to trigger an uncached response and with the second request we attempt to trigger a cached response. We determine whether a request was cached or not by parsing the response headers and evaluating the headers: `cf-cache-status`, `x-filebase-edge-cache`, and `x-cache`.

CID Source

We have two types of sources for CIDs that we request from the gateways: controlled and organic. The controlled CIDs correspond to random 1kB data blobs that we host on a controlled Kubo node in us-east-1. The idea is to use these blobs to measure a baseline performance of the gateways under controlled conditions.

The organic CIDs come from our Bitswap Sniffer tool that has picked them up by observing bitswap traffic. Measuring the retrieval performance for these CIDs can be used as a proxy to what users on average would perceive when interacting with IPFS gateways. It is useful to track long term trends.

Daily P50 Time to First Byte Latency for All Probed HTTP Gateways.