ZTE has conducted a field demonstration of optical networking equipment capable of transporting data at 1.7Tbps, the Chinese company announced yesterday.

The WDM-based system transported the data using eight channels, each with a capacity of 216.4Gbps, according to ZTE.

WDM (Wavelength Division Multiplexing), which is mainly used by operators in their core networks, sends large amounts of data using a number different wavelengths or channels over a single optical fibre.

The distance during ZTE's demonstration was 1,750km, and the company used a standard single mode fibreoptic cable, it said.

ZTE didn't detail when in expects to see products that can handle 200Gbps per channel. The goal with the demo was to show that an "upgrade from a 100Gbps transmission system to a 200Gbps system is possible," the company said.

ZTE isn't the only vendor that has conducted demonstrations to show its prowess when it comes to next-generation WDM systems. Last week, ZTE's Chinese competitor Huawei showed a prototype system that can handle 400Gbps per channel and offer a total capacity of 20Tbps.

Just like ZTE, Huawei didn't have any estimates for when its system will go on sale.

In the real world, operators are today moving to channel speeds at 40Gbps and 100Gbps, according to Infonetics Research. Carriers plan to use both 40Gbps and 100Gbps to the same degree in existing networks, but clearly favour the higher speed when building new networks, the market research company said earlier this year.

The biggest reason for upgrading from today's 10Gbps systems is that operators want to lower the cost per bit, Infonetics explained.