Standardising on tuneable lasers

The Optical Internetworking Forum (OIF) has announced the adoption of four Physical and Link Layer Implementation Agreements for tuneable lasers.

The Optical Internetworking Forum (OIF) has announced the adoption of four Physical and Link Layer (PLL) Implementation Agreements (IA) for tuneable lasers, SFI-4, Phase 2, VSR4-05 and VSR5.

The approval of the four IA’s brings the total number of IA’s approved by the OIF in 2002 to eight. The Physical and Link Layer Working Group of the OIF (PLL WG) also approved the formation of the Common Electrical I/O (CEI) project last week at the Forum’s quarterly technical committee meeting held in Orlando, FL.

‘With the approval of eight IA’s in 2002 the OIF continues to help bring technological advances and continuity to the industry,’ said Joe Berthold, OIF president.

<b>Tunable Lasers:</b> The first tuneable laser IA from the OIF PLL working group addresses the communication protocol, electrical interface and mechanical form factor interoperability for tuneable continuous wavelength (CW) lasers. This agreement defines a common form, fit, interface and function of a tuneable laser subsystem. Optical specifications are not included in the scope of the agreement due to the wide range of applications for tuneable lasers. This allows system and component vendors to reduce costs and increase interoperability and sourcing by targeting a common platform.

<b>SFI-4, Phase 2 – 10 Gbps interface for physical layer devices: </b> SFI-4, Phase 2 determines aggregate data bandwidths of OC-192 ATM and Packet over SONET/SDH (POS), as well as other applications at the 10 Gbps data rate. The typical line interface of a communications system with 10 Gbps optical links may consist of three separate devices: an optical module containing a SERDES component, a forward error correction (FEC) processor and a framer. The IA includes objectives and requirements for the interconnection between these devices requiring a parallel electrical bus operating significantly slower than the optical data rate.

<b>VSR4-05 – Very Short Reach (VSR) OC-192 serial interface including optical cross connects (OXC): </b>VSR4-05 includes both 4dB and 11dB optical link budgets, which covers distances from 2m to 600m. The 11dB option can be deployed in an optical network where the optical path includes a passive (transparent) photonic cross-connect (PXC), patch panels and up to 600m of single mode fibre.

<b>VSR5 – SONET/SDH OC-768 interface for VSR applications: </b>As the first 40 Gbps optical interface project defined by the Forum, VSR5 is four times faster than previous 10 Gbps interfaces and is a lower cost alternative to interconnect within a central office (CO). VSR5 is capable of nominal 40 Gbps aggregate bit rate intra-office systems for link distances up to 2 km. The IA specifies a set of functional SONET/SDH OC-768/STM-256 interfaces for VSR applications. The complete solution set is intended to address the set of reference applications, while minimising overall network and operational cost and complexity.

<b>Common Electrical I/O (CEI) Project: </b>The PLL WG has begun a new project to define electrical specifications for 4976 to 6+ Gigabit and 9.95 to 11+ Gigabit signalling. The CEI work will focus on both short reach (0 to 200 mm with up to one connector) and long reach (0 to 1m with up to two connectors) applications.

Launched in April of 1998, the OIF is a non-profit organisation with more than 250+ international member companies, including many of the world’s leading carriers and vendors.