China deploys three-band fibre for AI networks

China Mobile and partners have deployed a commercial three-band optical fibre system across about 35 km of an existing telecoms network in Qingdao. The design combines S, C and L optical bands with four fibre cores, with reported capacity gains aimed at AI, cloud and backbone data movement.

• 35 km commercial deployment combines S, C and L optical bands

• Four-core fibre aims to lift capacity without new cable routes

The fact

China Mobile and partners have deployed a commercial "three-lane" optical fibre system across about 35 km of an existing telecoms network in Qingdao. The design combines S, C and L optical bands with four fibre cores, meaning each core can act like a separate transmission path. The system can lift total traffic capacity by up to five times, with per-core throughput rising by nearly 50%, after engineering advances made the S-band commercially viable over distance.

The Assessment

Commercial networks already pair C-band and L-band, but the S-band has resisted clean amplification. If the system holds up, operators gain a practical lever to relieve AI and cloud data bottlenecks on backbone and data-centre interconnect links — relevant to China's East Data, Western Computing push. For readers who track optical transport, it signals that fibre expands capacity without the cost of trenching new cable.

What to Watch

Watch whether the system scales beyond 35 km and whether amplifier performance holds up in production. Also whether Chinese optical vendors cite the deployment in bids for backbone or submarine-cable projects.