SEPTEMBER 18, 2007 — Infinera completed two demonstrations, a field test of 40-Gbit/sec. transmission over 8,477 km and a lab test over 2,000 km, to promote high-bandwidth services transmitting on existing infrastructures with lowered costs and increased flexibility. The company used its large-scale photonic ICs (PICs) and digital virtual concatenation (DVC) protocol in the experiments.
The transoceanic transmission field trial took place in a live production network, and involved the service transmission of 40-Gbit/sec. OC-768/STM-256 service over a 1,969-km terrestrial network spanning Frankfurt to Paris to London to a trans-oceanic cable head-end on the English coast, then connecting to a 6,320-km subsea network, and then linking to another 188-km terrestrial backhaul network, reaching a cable landing site on the U.S. coast to New York. It used an Infinera DTN system equipped with a 40-Gbit/sec. tributary adapter module, which mapped one OC-768/STM-256 service into four 10-Gbit/sec. channels. This enabled 40-Gbit/sec. service transmission over an existing network infrastructure designed for 10-Gbit/sec. transmission. Infinera claims that these trials prove that 40-Gbit/sec., OC-768/STM-256 packet over SONET (POS), and other future high-bandwidth services — including 100-Gbit Ethernet (100GbE) — can be transmitted via existing infrastructures.
In a separate demonstration at Infinera's Columbia, MD, labs, researchers demonstrated 40-Gbit/sec. service transmissions over 2,000 km of fiber with high levels of polarization mode dispersion (PMD). This trial was designed to promote Infinera's 40-Gbit/sec. solution for real-world networks with fibers hindered by high PMD, and used DTN systems supporting 800-Gbit/sec. DWDM capacity. For this trial, 40-Gbit/sec. service was mapped into four 10-Gbit/sec. wavelengths before transmitting over 26 spans of fiber. Service was then reassembled at the receive end with error-free transmission. PMD was introduced into the line, with error-free transmission consistently maintained up to 65 psec. of peak differential group delay (DGD).
Infinera summarizes the results as facilitated by its PIC and DVC protocol products. The PICs consolidate ten 10-Gbit/sec. wavelengths into two monolithic ICs, providing 100-Gbit/sec. capacity in a single circuit pack. These are used in the company's DTN DWDM system. DVC protocol enables super-wavelength services to be mapped to the PICs' 10-Gbit/sec. transmissions then reassembled at the other end of the optical link, reportedly without errors. Future transmission goals include OC-768/STM-256 and 100GbE.