Active Optical Cables, Part 3

by Lisa Huff

The last of my summary of AOC Implementations, you can read Part 1 here and Part 2 here.

Reflex Photonics has gained an early customer base in InfiniBand and PCI Express extender applications with its SNAP 12 products, and is using the existing customer base to increase awareness of InterBoard products for data center customers. In developing InterBoard, Reflex Photonics moved into coarser channel implementations to meet industry AOC standards. The four-channel cables terminate in an array of 850nm VCSELs that use QSFP connectors suitable for both InfiniBand DDR and 40G Ethernet. What is also interesting about Reflex’s InterBoard is that it contains its optical engine technology, LightAble.

Zarlink (now part of Tyco) began its ZLynx product line with a CX4 interconnect, but quickly added QSFP as the module was standardized. Zarlink is unique in anticipating possible customer interest in dissimilar terminations by offering CX4-to-QSFP cables. Zarlink product developers say they will take the same attitude as CXP applications emerge. While most AOCs will use identical termination on both ends of the cable, the company will explore customer demand for hybrid connectors. Before it was acquired by Tyco, Zarlink was working on 40G implementations that were expected to be released this year. No announcements have been made as of yet, though. Tyco had its own QSFP AOC, namely the Paralight. It remains to be seen how Tyco will merge these product lines.

The first implementations of 40G Ethernet have indeed materialized as AOCs, but are expected to transition into actual optical modules as soon as transceiver manufacturers are ready with their products. What is nice for the end user is that if they want to implement 40G today, they can with AOCs and the same ports will then accept optical modules later if needed. InfiniBand AOC products are expected to stay as AOCs and not transition into optical modules, mainly because most of these connections are less than 30m so are easier to pull through pathways and spaces.

According to CIR, the market for AOCs is expected to be about $180 million (a rather small market for so many entrants) this year, most of which will be for data centers. However, by 2013, it is expected to grow to more than $1-billion – a steep climb and one that will need a lot of suppliers if it is actually going to happen.