SiliconBeat

Infinera, the Sunnyvale supplier of digital optical networking gear to telecommunications providers, got some bad news Wednesday from one of its biggest customers. Level 3 Communications told Infinera Wednesday that it will start using another vendor of digital wavelength-division multiplexing equipment beginning in the first half of 2010.

Infinera added that, even though Level 3 said it intends to continue to purchase products and services from it, the adoption of a new vendor “will impact the revenue we will receive from Level 3 beginning in the first half of 2010.”

Level 3 accounted for 25 percent of its revenues in the first half of 2009, when sales fell 58 percent year over year.