Sales of carrier Wave Division Multiplexing (WDM) systems surpassed that of Synchronous optical networking (Sonet) and Synchronous Digital Hierarchy (SDH) multiplexers for the first time in the first quarter of this year, new research reports.

Within the $1.4bn WDM market, the WDM Metro segment outperformed the Dense Wave Division Multiplexing long haul segment and grew 47 per cent over the year-ago quarter, according to Dell'Oro Group.

"With internet traffic growing at such high rates, service providers have to build optical networks that can handle enormous traffic volumes today yet can continue to scale in the immediate future," said Shin Umeda, vice president of optical transport research at Dell'Oro.

"WDM systems can clearly handle those requirements more economically than legacy Sonet/SDH multiplexers."

The report also shows that the WDM Metro market was highly fragmented in the first quarter.

Seven vendors accounted for over 80 per cent of the market, but none commanded more than 15 per cent revenue share.

Cisco was the market leader in the first quarter, followed closely by Alcatel-Lucent and Nortel.