Latency basics for Asia-Pacific services

Latency is more than a single number on a dashboard. For Asia-Pacific platforms it reflects geography, submarine cables, peering decisions and mobile network behaviour. Understanding these factors helps you design stress tests that look like real traffic instead of artificial lab experiments.

Why distance still matters

Signals move close to the speed of light, but fibre paths are rarely straight. Routes between Tokyo and Singapore or Mumbai and Sydney often travel thousands of kilometres under the sea. Even a perfectly tuned stack cannot break physics.

Subsea cables and landing points

Most international traffic in Asia flows through a few busy cable systems and landing stations. When a cable is congested or under maintenance, latency and packet loss can spike for entire regions. Good stress tests take this into account by:

• Running scenarios from multiple locations, not just one cloud region.
• Comparing performance when traffic enters through different landing points.
• Watching not only averages but also tail latency (p95 and p99).

Peering and transit

Two networks in the same city may still send packets through a distant transit provider if they do not peer locally. That is why users on mobile and fibre can see different paths to the same service. When planning tests, try to include:

• Traffic from at least two major ISPs per country where you have many users.
• Both mobile and fixed-line connectivity where possible.
• Separate measurements for DNS, TLS handshakes and application responses.

Incorporating latency into stress tests

Instead of only pushing raw bandwidth, combine capacity tests with latency-aware goals. For example, you might decide that:

• Home pages for key markets must stay below 200 ms at p95 during a promotion.
• API calls that drive your mobile apps should remain under 300 ms at p95.

From there, design stress scenarios that gradually increase traffic from relevant regions until those thresholds are reached. The resulting numbers are far more useful for product teams than a single "maximum requests per second" figure.

If you need a platform to run these scenarios, you can create an account and focus on tests for infrastructure you control.