Samoa & Tonga: Internet at the Edge of the World

Samoa and Tonga are two Polynesian states in the South Pacific. The nearest continent, Australia, is more than 3,000 km of open water away; Europe is over 17,000 km away. No surprise that the internet can feel expensive and sluggish here. What is more interesting is what our measurements show: latency towards Tonga can swing from 297 ms to 995 ms within a single traceroute — a threefold change in a matter of seconds.

That is not measurement noise. It is what “edge-of-the-world” connectivity looks like when redundancy is limited and the last ocean hop is doing too much work.

Look at hops 16–21: they all geolocate to Apia, Samoa, inside the same ASN. Yet the RTT jumps around: 297 ms, 728 ms, 764 ms, 346 ms, 730 ms, 995 ms. The packet is already “there” — but the network is clearly struggling at that moment.

Cogent routing: Belgrade to Sydney without an American detour

The path from Tbilisi to Samoa goes through Cogent Communications (AS174), one of the largest Tier‑1 carriers. Here, the routing is geographically sensible: Belgrade → Milan/Marseille → Singapore (209 ms) → Perth → Sydney.

From a mapping point of view, this is close to optimal: Europe → Asia → Australia, without tromboning via the US. The trouble starts after Sydney, on the ocean leg.

Vodafone Samoa: the “last mile” where queues explode

Vodafone Samoa (AS17993) handles the island-side reachability. In small Pacific markets the long-haul often looks fine up to Australia, while the Australia → islands segment is where capacity constraints, shaping and buffering become visible.

RTT spikes like we see in Apia are frequently consistent with congestion + bufferbloat: packets are not necessarily dropped, but they sit in oversized queues, adding hundreds of milliseconds of delay.

Samoa’s cable map (why it is usually steadier)

Samoa is in a better position than many microstates in the region because it has multiple international subsea paths. A key one is Tui‑Samoa: roughly 1,470 km of fiber linking Samoa to Fiji (with branches to Wallis & Futuna). It entered service in February 2018 and was built as a modern system with high aggregate capacity (about 16 Tb/s).

From Fiji, Samoa can reach larger trans‑Pacific backbones, including Southern Cross. The baseline latency is high (physics), but the route can be stable when the ocean leg is not saturated.

Tonga: one international cable, one obvious failure domain

Tonga’s primary link is the Tonga–Fiji Submarine Cable (often just Tonga Cable): about 827 km from Nukuʻalofa to Suva (Fiji), where it connects to international networks (including Southern Cross). It went live in 2013. It replaced satellite as the default — but it also concentrates risk into a single line in the ocean.

When a volcano cut a country off

That risk became headline news in January 2022, when the Hunga Tonga–Hunga Haʻapai eruption damaged Tonga’s international cable in multiple places. Geological reporting notes the main international cable was repaired by 21 February and connectivity was restored by 22 February 2022, after teams had to re‑splice multiple sections and replace a missing segment likely buried by seabed flows.

On small islands, “repair time” is not just the splice itself: the ship must reach the site, and the work is done in difficult seabed terrain and volatile geology.

Satellite as a stopgap (and why it hurts)

When the cable is gone, satellites become the emergency option. In the region, geostationary capacity (for example Kacific1, launched in December 2019, a Ka‑band high‑throughput GEO satellite with many spot beams) is often used for back‑up connectivity. GEO orbit is ~35,786 km above Earth; even ideal physics implies roughly 240–280 ms delay per “ground–satellite–ground” hop, and real-world round‑trip delay commonly ends up around ~600 ms or more once processing and routing overheads are included.

Big numbers, simple physics

Even on a perfect path, Samoa and Tonga are far: light travels slower in fiber than in vacuum, and cable routes are never straight lines. So a stable 300–400 ms RTT from Europe/Caucasus towards Samoa is not mysterious; what is unusual is the sudden 300+ ms swings inside the same city and the same ASN.

Monitoring

• Samoa RTT: typically ~380–400ms (often stable)
  Operator: Cogent → Vodafone Samoa
• Tonga RTT: can approach ~1s during congestion / limited redundancy
  Single international failure domain remains the core risk
• Path: Tbilisi → Belgrade → Marseille → Singapore → Perth → Sydney → Apia
• Key risk: Tonga relies on one primary international cable; 2022 showed how exposed that is