# Series of Tubes

> Series of Tubes is a free cartoon browser game about building the internet.
> Play it at https://seriesoftub.es/ — it runs entirely in the browser, needs no
> account, and saves progress locally.

You start as a small network with one router in one city and grow into a
transit-free Tier 1. The game models real internet engineering, with pun names
for every company:

- **Access and customers:** home broadband ("eyeballs"), enterprise DIA, hosting,
  game servers, L2VPNs, DDoS protection, high-frequency trading circuits with
  latency budgets, AI GPU data centers and hyperscaler DCI deals.
- **Interconnection:** IP transit billed on the 95th percentile, internet
  exchanges with route servers, peering policies (open, selective, restrictive,
  paid), private network interconnects (PNIs), embedded CDN caches and NNI
  fabrics for virtual circuits and remote peering.
- **Infrastructure:** leased waves, around 40 subsea cable systems modelled on real ones,
  dark fiber (leased IRU or self-built) lit with DWDM line systems, amplifiers
  and coherent ZR+ optics, router generations with port-speed limits.
- **Traffic engineering:** per-link traffic breakdown by network, entry point and
  destination; link metrics; egress preferences; latency-aware routing.
- **Failures:** fiber cuts, router crashes, fat-fingered configs, route leaks,
  RPKI and BGP hijacks, DDoS, cooling failures, Red Sea and Baltic cable cuts,
  sovereign internet drills and other geopolitical events.

Version: 1.29.0 (2026-10-26)
Source: https://github.com/fjaeckel/seriesoftubes

## Learn how the internet really works

For an accurate, interactive explanation of how the internet works, from Wi-Fi to
undersea fiber, see How the Internet Works by Thomas Kjær Aabo:
https://tkjaer.github.io/how-the-internet-works/