Email delivery: Hate phishing emails? You'll love DMARC

It's been quite a weekend for fans of fast fibre, with Ciena and BT demonstrating 800 Gbps superchannels, and Bell Labs offering a glimpse of higher speed submarine cables.

Announcing the deployment at BT, Ciena noted that while laboratory speeds are far faster than 800 Gbps, the UK deployment covered an already-deployed 410 km link between BT's Adastral Park Research and Development Centre in Ipswich and BT Tower in London.

The Ciena announcement notes that the transmission was achieved over a link with high polarisation mode dispersion (PMD), which couldn't even carry 10 Gbps using standard transceivers.

In one trial, a 400 Gbps 16QAM channel was operated alongside 40 Gbps and 100 Gbps QPSK channels on their own wavelengths.

Meanwhile, Bell Labs is about to publish a paper in Nature Photonics in which a group led by Dr Xiang Liu demonstrates international-scale transmissions at 400 Gbps.

Their research demonstrates a way to deal with the non-linear distortion which grows worse with distance. In their paper, Dr Liu, Peter Winzer and their research team say the performance they achieved over 13,000 km links is four times the previous 100 Gbps record for similar distance. ®

5 ways to reduce advertising network latency