Active optical cable exceeds copper rates

28 Nov 2012

Lowers 10G link costs, boosts server integration, doubles reach, weighs 75% less than copper cable.

Avago Technologies, a developer of analog interface components for telecoms and industrial applications, has launched a range of active optical cables and associated high density communications modules such as SFP+ (small form factor pluggable) QSFP+ (quad), and CXP versions. The cable and systems, which are intended for computing and datacenter applications, have performance parameters that Avago says surpass those of active copper cables.

The company states that its new active optical cable assemblies, which use proprietary technology, yield a lower cost per 10G link than active copper cables. Combined with performance increases, lower weight and easier cable management, this active optical cable enables a high data throughput interconnects up to 100m.

The wider Avago AOC portfolio includes 10GbE SFP+, 40GbE QSFP+ and 150G CXP active optical cable offerings. The suite offers an alternative to copper cable while offering the benefits of optical fiber. AOCs use a cabling technology that accepts the same electrical inputs as a traditional copper cable, but use optical fiber between the connectors with electrical-to-optical conversion on the cable ends that improves speed and reach of the cables.

Market expansion

Avago would appear to have come up with this improved design of optical cable in good time for a market expansion. The AOC market is projected to grow to just under $100 million by 2015, according to market analyst LightCounting's recent forecast.

Brad Smith, senior VP and industry analyst for data center interconnects at Lightcounting, commented, "The main market continues to be in high performance computers or supercomputers operating with the InfiniBand protocol. Over the past couple of years, AOC adoption in data centers using the Ethernet protocol to connect switch layers together and also in telecom applications, interconnecting long-haul DWDM and routers in central offices has grown."

Sharon Hall, Product Line Manager for Avago fiber optic products, said, "Our new AOC products strengthen our position in high bandwidth pluggable optics technology. Applying our proven design technology and volume manufacturing expertise is expanding access to a broader variety of previously copper-only market segments."

Driven by the increasing need for greater bandwidth and applications in cloud computing environments, AOCs are the latest solutions for communications within data centers, server farms, network switches, telecom switching centers and other high-performance embedded applications requiring high-speed data transfers. Applications include data aggregation, backplane communications, proprietary protocol data transfers, and other high-density/high-bandwidth applications.

AOCs have numerous advantages over direct attach copper as are used in previous-generation applications which cannot provide the features that are required by today's performance-enhanced applications. The bit error rates for Avago AOCs are 10-15 compared to DAC that is 10-12.

AOCs' EMI immunity is better than DAC as the high frequency EMI signal is confined within the pluggable modules while only the optical signal is transmitted along the cable. Furthermore, the weight of an AOC is about 25% of DAC, has a smaller cable diameter and offers a minimum cable-bending radius of only 30mm, much better than DAC. These positive advantages give customers the right solution and form factor to meet their high density optical interconnect specifications.

About the Author

Matthew Peach is a contributing editor to optics.org.