Acacia Communications (NASDAQ: ACIA) officially launched a battle between CFP2-DCO and CFP2-ACO optical transceivers for pluggable interface control. The company has announced its digital coherent optical (DCO) optical module which supports 100 and 200 Gbps operations.

CFP2-DCO is different from CFP2-ACO (for "analog coherent optics"), because the transceiver contains a coherent DSP ASIC or ASSP within the module. CFP2-ACO relies on DSPs hosted on line cards (see "OIF Approved CFP2-ACO Implementation Agreement").

Therefore, CFP2-ACO is much easier to design, develop and manufacture. Some optical transceiver vendors, especially those that do not have DSP ASIC expertise, have added CFP2-ACO to their portfolios, and optical modules are readily available. Although Acacia does not publicly disclose the price of its CFP2-DCO, the DSP equipment in the module may mean the cost is more than the typical CFP2 ACOS. The lack of DSP's ASIC also means that the CFP2-ACO can be matched with the system's own DSP ASIC or with commercial silicon such as NER or Inphi (by acquiring CLARPHY communication). Therefore, CFP2-ACO has a wide range of addressable market and the advantage of first-to-market.

However, the line cards designed for CFP2 ACS must have DSP devices pre-installed for each port, and all ports will be initially used. Therefore, the total line card cost of using CFP2 ACOS and -DCOS may be significantly reduced. The CFP2-DCO method is also capable of increasing coherent communication capabilities to deploy systems that were not originally designed for this operation (as long as the system is suitable for the CFP2 form factor).

The tricky part is to stuff the DSP function into the small size of CFP2. Acacia

Communications uses its 16nm CMOS MELU DSP ASIC pairing with silicon photonic IC expertise to create its modules. It is the same case with most CFP2-ACO competitions, the Acacia communication optical transceiver uses QPSK modulation for 100 Gbps operation, or 8QAM or 16QAM 200 Gbps. It also provides internal layer 1 encryption.

The Acacia 200 Gbps CFP2-DCO is popular for 2H17. This is unparalleled in performance and power consumption," said by Cinnamon's founder and leading analyst Andrew Schmitt through the Acacia Newsletter.

In fact, it supports 80 km arrival equipment as a competitor's upcoming PAM4-based direct inspection optical module for short-distance data center interconnect applications.