Fibre Channel over the Long Haul


One of the first things the Fibre Channel community realized as the age of unified fabrics approached was that it would have to find a way to make nice with the Ethernet. Enter Fibre Channel over Ethernet (FCoE).


But the other thing was that the technology needed to have a greater presence over the long haul, offering enterprises a means to consolidate storage on a regional, national or, conceivably, international basis. Sure this could be done through the Ethernet again, but how much cooler would it be to have native wide area Fibre Channel?


To get there, though, the technology would need support from the optical networking community. And it looks like that support is coming through this year as a wave of FC-capable transceivers and support technology is heading to market.


Avago Technology just announced the availability of the AFCT-57D5ATPZ transceiver, the first to support 8G Fibre Channel in an SPF+ LR (Long Reach) format. The device operates over single-mode fiber, delivering up to 8.5 GB over distances as long as 10 km. It is built on the company's 1310 nm DFB laser, offering backward compatibility to 2 and 4 G Fibre Channel formats.


In Europe, Italian optical systems developer Mitel-Teleoptix recently tapped new physical layer (PHY) technology from Applied Micro Circuits for its new 80-km XFP transceiver module. The move adds Fibre Channel support along with 10 GbE and SONET for both Time Division Multiplex (TDM) and Dense Wave Division Multiplex (DWDM) applications. Mitel said it chose AMCC by virtue of the company's forward error correction (FEC), electronic dispersion compensation (EDC) and clock-and-data recovery (CDR) technology.


Broadcom is upping the ante with its own physical layer devices with a new low-power system that supports 10G Fibre Channel, as well as 10 GbE, SONET and Optical Transport Networks (OTN). The 10G PHY family supports rates ranging from 9.953 to 11.35 Gbps and is suitable for everything from optical switches and routers to multi-service switching platforms and long-haul DWDM transports.


A new series of laser drivers from Vitesse Semiconductor will also help put Fibre Channel on the wide area. The VSC7985 and 7986 units are built on a unique power architecture designed to meet the 1W requirements of 8G Fibre Channel over SONET and SDH fiber networks. The single-chip solution conforms to the SFP+ footprint but still supports up to 48 ports of 8G Fibre Channel and is suitable for both long-haul and short-reach applications.


A wide area storage network is a tempting option for those looking to leverage their existing enterprise storage infrastructure. You can still do the same thing with 10 GbE, and probably cheaper, but it's nice to know that at least you have a choice of protocols.