The Optical Internetworking Forum (OIF) has released a whitepaper on line-side 400-Gbps optical transmission technology and requirements that promises to shape its specification work in this area (see "OIF tackles 400G Framework Document"). The group also has updated its integrable tunable laser work and released a new implementation agreement designed to ease the implementation of ITU-T recommendations on automating link configuration processes.
The whitepaper, "Technology Options for 400G Implementation,” is a joint effort by the OIF's Physical Link Layer Working Group and Carrier Working Group. It includes input from carriers on system parameters and network requirements. The authors review the fundamental challenge 400G currently presents – that the most commonly discussed alternatives to aggregating four channels of DP-QPSK for 400G may provide the necessary data rate, but at the cost of lesser reach. They then review the most promising approaches in the context of both long-haul and metro fiber-optic network applications. These include various flavors of QAM as well as orthogonal frequency-division multiplexing (OFDM).
"As the industry moves forward towards 400G-transmission speed, it is crucial to have carriers and vendors working together, as was achieved with 100G optical interfaces,” said Karl Gass, of Qorvo and the OIF PLL working group chair, optical. "This whitepaper summarizes the requirements by carriers for specific technology applications, and we expect to start projects to define the best, near-term solutions for 400G networks.”
The whitepaper is available on the OIF's website.
Meanwhile, the OIF also has cranked out some new implementation agreements. The group has tweaked its Integrable Tunable Laser Assembly MSA and Micro-Integrable Tunable Laser Assembly implementation agreement to add the provision of high-resolution registers and raises the protocol version to 3.0.0. The changes enable the devices to keep pace with increasing requirements for flexible networks, the OIF says.
New on the implementation agreement roster is "Neighbor Discovery Implementation Agreement 1.0.” It builds on the ITU-T's work on automating link identification and exchanging link configuration data within G.7714 and G.7714.1. With an eye toward expanding implementation of the ITU-T recommendations, the new implementation agreement specifies the exchange of the following information:
- identity of the network element port connected to the far end of the link
- data-plane capability of the network element ports on each link end
- management-plane details for each link end
- control-plane details for each link end.
For more information on high-speed transmission systems and suppliers, visit the Lightwave Buyer's Guide.