Q: What is the focus of the ACC MSA?
A: The ACC (Active Copper Cable) MSA brings together diverse members from across the networking industry to define the necessary electrical specifications to enable a robust ecosystem of compatible twinax copper based cabling products. There is a market demand to reduce power in high-density network deployments and ACC cables stand out as a significant opportunity to do that. Ensuring the expected plug-and-play interoperability in an copper cabling regime requires bringing this diverse group of experts together to define these specifications. The ACC-MSA will address architectures that involve linear equalizer based copper interfaces.
Q: What are Active Copper Cables (ACC)?
A: Active Copper Cables refers to a solution that utilizes a low-power equalized twinax cables that do not incorporate a DSP chip. The signal path from end to end in the link is considered linear, enabling lower power consumption through specialization. As with AEC cables with a DSP, an ACC-MSA compliant link will work in a full range of networking and computing equipment such as switches and NICs.
Q: What are the advantages of ACC?
A: By eliminating the DSP/retimer function, ACC cables extend cable reach but are lower power, lower cost, and lower latency than competing solutions.
Q: How does ACC work?
A: Modern Application Specific Integrated Circuits (ASIC) in a switch or Network Interface Card (NIC) have extremely capable transmitters and receivers which can compensate for significant link degradation. These capabilities are usually not fully utilized, however, when connected through a retimed copped cable. When ACC cables are used, the link becomes a seamless linear channel, and the full capabilities of the ASIC transmitters and receivers can be utilized for equalization. This ACC-based link has much lower power than if a retimer was used.
Q: How is an ACC cable different to a cable using retimers?
A: Since the equalizer based ACC cable is operating linearly, it is not making complex digital operations and decisions. The entire signal path utilizes the modern ASIC’s equalization capability, allowing for a more simple, optimized solution. This is in contrast with retimed AEC cables where the DSP in the cable connector makes complex digital operations and decisions in both the transmit and receive paths in the DSP which consume power. Without the DSP, the ACC cable lower power, lower cost, and lower latency.
Q: What are the system requirements for using ACC?
A: Systems compatible with ACC cables require capable ASICs and well-designed transmission lines. Any pluggable connector form factor can be used to make ACC cables since the architecture easily fits in associated power envelopes.
Q: How does this MSA relate to other industry standards?
A: The ACC-MSA complements and builds upon other industry standards, such as IEEE 802.3 and OIF, and MSAs such as OSFP or QSFP-DD. The ACC-MSA will specify product and system-level interoperability requirements that span both the electrical and optical interfaces operating at 100 Gb/s per lane and above.
Q: Will ACC work with Ethernet Traffic?
A: Yes, ACC-MSA compliant modules are protocol agnostic. The initial MSA specifications will be optimized for Ethernet data rates.
Q: Is ACC as robust as a DSP-based solution?
A: Yes, ACC-MSA compliant module is as robust as DSP-based module solutions. The ACC-MSA will develop specifications which provide this level of robustness across the copper networking ecosystem.
Q: Will the ACC-MSA’s specifications ensure interoperability?
A: Yes, the ACC-MSA will ensure interoperability between network equipment and ACC-MSA compliant modules. The specifications developed by its members will ensure multi-vendor interoperability.
Q: Will the ACC modules work on every port in my switch?
A: Yes, the specifications will ensure that any ACC-MSA compliant port on a switch or NIC (or other network equipment) will work with any ACC-MSA compliant cables.
Q: What will be the initial focus of the MSA?
A: The initial focus of the ACC-MSA is to ensure interoperability of links consisting of only ACC cables utilizing twinax cable of various gauges. The length of supported cable will depend on cable gauge and data rate per lane.
Q: What else will the ACC-MSA be working on?
A: Beyond the initial 200 Gb/s specifications, the ACC-MSA has a roadmap that will address lower and higher per lane data rates including 400 Gb/s.
Q: Will the ACC-MSA coordinate interoperability testing?
A: No, ACC-MSA members will self-test ensuring interoperability.
Q: Do you have a nomenclature defined yet?
A: Yes, a fully linear module is called an ACC module and we will define electrical specifications that will be designated with a “-ACC”.
Q: When will the MSA publish their specifications?
A: The release of the first specifications are targeted for Q2 ’26.
Q: Can I join the MSA?
A: Please see the ACC-MSA website for contact information. We expect to be welcoming new members after we publish our initial specifications.