Infinera pushes limits on trans-Pacific transmission

NTT subsidiary Pacific Crossing today said it has completed a test of an undersea cable operating at 100 Gb/s using a couple of different flavors of Infinera’s optical platforms.

The subsea market represents perhaps the longest of long-haul markets, with carriers trying to get transmission speeds up to 100 Gb/s to both meet the growing demand for shear bandwidth – and to be able to do so more flexibly and affordably. In subsea especially, operators need to squeeze every ounce of bandwidth out of their existing fiber deployments, said Mark Showalter, Infinera’s senior director of marketing.

The 9500 km trans-Pacific run demonstrated by Pacific Crossing represents one of the longest – if not the longest – distances traversed at a full 100 Gb/s, according to Infinera. The previous longest 100 Gb/s sub-sea connection it could find was about half that distance, or about 4000 km, Steve Grubb, Infinera fellow, told Connected Planet.

The Pacific Crossing trial tested two flavors of 100 Gb/s optical transmission. The first was a 100 Gb/s client service carried on 40 Gb/s optical channels using Infinera’s FlexCoherent transmission on its current DTN platform. The second trial delivered a full 100 Gb/s optical channel using binary phase shift keying (BPSK) modulation on Infinera’s recently announced DTN-X platform (CP: Infinera delivers 100G coherent transmission, 500G 'super-channels’), which will be commercially available in the first half of next year.

BPSK modulation, which Infinera execs said was key to enabling the long-distance transmission, has not yet been formally announced as part of the DTN-X, but will be available in the future. Using BPSK versus quadrature phase shift keying (QPSK) modulation “traded off spectral efficiency for distance,” Grubb said, joking that in the subsea market, “reach is not negotiable.”

Even as long-haul transmission reaches 100 Gb/s and higher, carriers are still mainly dealing with a 1 Gb/s and 10 Gb/s mix of services. “Customers just see a pool of bandwidth and really can put any mix of services on it,” Grubb said.
While NTT is an announced Infinera customer, Pacific Crossing is not at this point, Infinera execs said. That makes the deployment a trial, with no announced commercial deployment plans as of yet.

Elsewhere, Infinera has completed several recent trials of 100 Gb/s and 500 Gb/s super-channel links, including recent tests with SEACOM in Africa and Interoute in Europe, the vendor said.