Standard international routes are generally designed to provide global connectivity at a reasonable cost. They are not necessarily optimized specifically for traffic between overseas servers and mainland China.
BGP plays an important role in determining which network path your traffic takes, but high latency or packet loss does not mean that BGP itself is malfunctioning.
A typical connection may look like:
Proxy server → International transit provider → Chinese carrier international gateway → Your local ISP
On standard routes, traffic may be carried through regular international transit providers. The selected route is usually based on the provider's network policies, upstream relationships, availability, and cost — not necessarily on which path provides the lowest latency or best performance for users in mainland China.
This can result in several common situations:
• International congestion: Interconnection capacity between an overseas transit provider and a Chinese carrier may become congested, particularly during peak hours. This can result in packet loss, unstable latency, TCP retransmissions, and lower throughput.
• Different outbound and return routes: The route from your device to the proxy may be different from the route used by the proxy to send data back to you. A normal ping or outbound traceroute therefore does not always represent actual download performance.
• Different IPs may use different routes: Even IPs located in the same country, data center, or provider network may belong to different IP ranges or upstream routes. As a result, one IP may perform significantly better than another when connecting to mainland China.
• Routing conditions can change: Internet routing and congestion are dynamic. A route that performs well at one time may become slower during peak periods or after an upstream routing change.
This is why a proxy server can have sufficient local bandwidth while a user in mainland China still experiences slow speeds or packet loss. In such cases, the bottleneck may be the international network path rather than a bandwidth limit applied to the proxy itself.
For users in mainland China who place a high priority on connection quality, we recommend considering routes specifically optimized for China, such as CN2 GIA, China Unicom 9929, or CMIN2, where available.
These optimized routes generally use more deliberate routing policies and higher-quality international connectivity for China-bound traffic. However, actual performance can still vary depending on your local ISP, location, network congestion, and current routing conditions.
In simple terms:
Standard routes prioritize general connectivity and cost efficiency, while optimized routes are designed to provide a better network path for users connecting to and from mainland China.
