Optical Internetworking Forum Debuts Very Short Reach Interface Specifications; Provides Cost Savings for Central Office Interconnection
Source: Optical Internetworking Forum (OIF)
FREMONT, Calif. The Optical Internetworking Forum (OIF) announced today the adoption of two Very Short Reach (VSR) OC-192 interface Implementation Agreements. These VSR interfaces are intended to help reduce the cost of OC-192/STM-64 links between equipment in a single central office (CO). The first specification, OIF-VSR-01.0 (VSR-1) is titled Very Short Reach (VSR) OC-192 Interface Based on Parallel Optics. VSR-1 has 12 fibers at 1.25 Gbit/s each, uses 62.5um-core multi-mode ribbon fiber and reaches up to 300 meters. The second specification, OIF-VSR-02.0 (VSR-2) is titled Serial OC-192 1310 nanometer Very Short Reach (VSR) Interfaces. VSR-2 uses single mode fiber (SMF) and reaches up to 600 meters.
VSR-1 and VSR-2 are complementary. VSR-1 uses lower speed signals and has the potential to be the lowest cost OC-192 link. It is particularly suitable for the shortest reaches, where the ribbon fiber can be treated like any ordinary patch cable. VSR-2 uses installed SMF and can reach across very large COs. The OC-192 VSR interfaces interconnect co-located equipment such as routers, Dense Wavelength Division Multiplexers (DWDM), optical cross-connects, and SONET/SDH Add-Drop Multiplexers (ADMs) within a CO.
"Using existing interfaces designed for longer distances results in unnecessary cost," said Russ Tuck, chairman of the OIF s Physical and Link Layer Working Group. "Carriers and network service providers can save thousands of dollars per interface by using OIF VSR interfaces to link co-located equipment."
VSR-1: Very Short Reach (VSR) OC-192 Interface Based on Parallel Optics
VSR-1 adapts high-volume Gigabit Ethernet technology in the form of 1.25 Gbit/s signaling with 850 nanometer lasers over multi-mode fiber. VSR-1 uses 12 of these channels over ribbon fiber and reaches up to 300 meters. The 12 lasers can be implemented with a single Vertical Cavity Surface Emitting Laser (VCSEL) array. 10 of the fibers carry data, one carries CRC error detection codes, and the 12th fiber carries parity of the 10 data fibers. This enables hitless correction of errors on any single fiber, including the loss of a fiber. Field termination of the multi-mode ribbon fiber is supported. The link electronics automatically adapt to either ribbon orientation, so there is no such thing as a twisted ribbon or a connector put on upside down.
The components required to implement VSR-1 are now available from suppliers, and OIF members have demonstrated multi-vendor interoperability of the interface.
VSR-2: Serial OC-192 1310 nanometer Very Short Reach (VSR) Interfaces
VSR-2 is based on ITU G.691. It uses 10 Gbit/s serial signaling with a 1310 nanometer laser over SMF and reaches up to 600 meters. Compared to SONET Short Reach (SR) interfaces, it relaxes some optical parameters. It allows increased dispersion and reduced reach with the intent of enabling lower cost devices.
About the OIF Physical & Link Layer Working Group
The OIF Physical and Link Layer (PLL) Working Group creates Implementation Agreements (IAs) for critical interfaces between and within optical internetworking equipment. This helps increase interoperability and reduce costs. Last year, the OIF PLL created IAs for the interfaces on both sides of OC-192 framers. It recently began work on OC-768 VSR and framer interfaces.
The OIF Implementation Agreements, including VSR-1 and VSR-2, are available at http://www.oiforum.com/public/technical.html.
About the OIF
Launched in April of 1998, the OIF is a rapidly growing, non-profit organization with 300+ member companies to date, including many of the world s leading carriers and vendors. As the only industry group uniting packet and voice networks, the OIF helps advance the standards and methods of optical networks. The mission of the OIF is to foster the development and deployment of interoperable products and services for data switching and routing using optical networking technologies.
With the goal of promoting worldwide compatibility of optical internetworking products, the OIF actively supports and extends the work of national and international standards bodies. Formal liaisons have been established with The ATM Forum, IEEE 802.3 HSSG and the IETF. More information on the OIF can be found at www.oiforum.com.
CONTACT: Porchivina and Associates Kendra Gross, 415/893-9138, Fax: 415-893-8185, kendra@papr.com
Porchivina and Associates
Kendra Gross, 415/893-9138, Fax: 415-893-8185, kendra@papr.com
E-mail: kendra@papr.com
Web site: http://www.oiforum.com
