Taurus Ethernet Smart Cable Modules™
Astera Labs delivers Taurus Smart Cable Modules™ (Taurus SCM™) that overcome reach, signal integrity and bandwidth utilization issues for 100G/Lane Ethernet connectivity for Switch-to-Switch and Switch-to-Server applications.
The Taurus SCM portfolio enables a cost-effective, active solution for 200/400/800G Ethernet rack connectivity with built-in advanced fleet management and deep diagnostic capabilities, 50% lower power, <100 ns latency, and 3-meter reach over thin copper gauge cables. Taurus SCM facilitates a flexible supply chain of Smart Electrical Cables by qualifying with leading cable vendors to support Taurus capabilities in QSFP-DD and OSFP backshells.
- Supports 100G PAM4 (106.25 Gbps), 50G PAM4 (53.125 Gbps), 25G NRZ (26.5625 Gbps and 25.78125 Gbps), and other Ethernet line rates
- Resolves rate mismatch between NICs and switches with 50G-to-100G PAM4 & 25G-NRZ-to-50G-PAM4 aggregation/disaggregation (Gearbox)
- 36-dB reach extension for up to 3-meter, 34AWG copper cables, ensuring sufficient cable length and flexibility.
- Ultra-Low-Latency data path supports < 100 ns.
- Advanced fleet management capabilities with full CMIS Features, security, and extensive diagnostics: cable degradation monitoring, host-cable security, multiple loopback modes, pattern generation/checking
- Qualified with leading cable vendors to enable Smart Electrical Cables (SECs) in QSFP-DD and OSFP backshells.
System Block Diagram
Orderable Information
Taurus Ethernet Smart Cable Modules
| Orderable Part Number | Description | Max Data Gen | Cable Line Rate | Mode | Package / Connector | Ordering |
|---|---|---|---|---|---|---|
| EM400-QDX | 400G QSFP-DD Taurus Smart Cable Module | 400G | 50G/Lane, 100G/Lane | PAM4 | QSFP-DD | Contact Us, https://www.asteralabs.com/product-details/em400-qdx/ |
| EM400-EPS | 400G OSFP Taurus Smart Cable Module | 400G | 50G/Lane, 100G/Lane | PAM4 | OSFP | Contact Us, https://www.asteralabs.com/product-details/em400-eps/ |
| EM800-EPS | 800G OSFP Taurus Smart Cable Module | 800G | 100G/Lane | PAM4 | OSFP | Contact Us, https://www.asteralabs.com/product-details/em800-eps/ |
| EM800-QDX | 800G QSFP-DD Taurus Smart Cable Module | 800G | 100G/Lane | PAM4 | QSFP-DD | Contact Us, https://www.asteralabs.com/product-details/em800-qdx/ |
| EM200-QDX | 200G QSFP-DD Taurus Smart Cable Module | 200G | 25G/Lane | NRZ | QSFP-DD | Contact Us, https://www.asteralabs.com/product-details/em200-qdx/ |
Why Use Taurus Smart Cable Modules?
Taurus SCMs enable robust, easy-to-design 100G/Lane Ethernet connectivity and provide all the benefits of basic Active Electrical Cables, while also offering built-in advanced fleet management, security, and deep diagnostic capabilities critical to ensuring high reliability and up-time.
Robustness
Extended Cable Line Rate: future proof scalability for 200G/400G/800G
Low Power: uses 50% less power than Active Optical Cables
Low Latency: Low latency operation at < 100ns
Security: Advanced security features help prevent malicious attacks of unauthorized firmware loading, module diagnostics access, and configurations
Easy System Design
Thin Cable Gauge: Up to 34AWG
Fewer Twinax Pairs: 8 pairs at 200G/400G/800G reduces overall external diameter of cables
Extended Reach: Up to 3m of reach at 34AWG
Flexible Supply Chain: Taurus Smart Cable Modules are compatible with multiple cable vendors for easy second sourcing of active cable assembly
Fleet Management
Quick Debug: Self-test features enable rapid troubleshooting
Deep Diagnostics: Cable-side and host-side diagnostics enable easy management of entire fleets
The Difference is Clear
Taurus SCMs deliver cloud service providers system-wide visibility and management features, which enable enhanced security options, quick debug tools, and flexible firmware upgrade capabilities — all of which basic Active Electrical Cables cannot match.
Videos
Taurus Smart Cable Module™ 400GbE PAM4 Connectivity Demonstration
See a Taurus Smart Cable Module™ enabled 400GbE PAM4 Smart Electrical Cable in action with a demonstration of an end-to-end 400GbE link up passing error-free traffic as well as real-time link diagnostics.
FAQ
- At 50Gbps/lane, passive direct-attach copper (DAC) cables barely reach 3-meters. At 100Gbps/lane, DACs may only have a 2-meter practical reach limit.
- The switch PCB consumes too much of the channel budget, which then limits the cable reach and increases cable gauge.
- DACs are rigid, heavy, and bulky, restricting airflow for system cooling and making rack servicing difficult.
- Optical modules have high power consumption. A 400G module consumes around 12W and a 800G module may consume up to 20W.
- Optical modules require advanced low loss materials which are expensive.
- Optical modules have a shorter lifespan and are less reliable compared to active copper cables. Data center operators need to constantly maintain and replace the failed optical modules.
- Active Optical Cables (AOC) can be used for rate conversion and to achieve thin wire profile. However, such optical designs incur additional costs, reliability concerns, and require more power.
- Active Copper Cables (ACC) can be used for rate conversion, have a lower design cost when compared to AOC while also supporting even thinner gauge cabling as compared to passive DACs. General purpose ACCs are limited by their lack of diagnostics and security features.
- Smart Electrical Cables (SEC) that utilize Taurus Smart Cable Modules have all the benefits of an ACC with the added “”smarts”” required by Cloud Service Providers.
- Switch-to-server: ToR Switches to Network Interface Cards (NIC) interconnects on a server.
- Switch-to-switch: within a spine switch and spine switch to Exit Leaf interconnects.
Taurus Smart Cable Modules can provide gearbox functionality at 200GbE from 4x50G to 8x25G.
- Rate mismatches between NIC and switch lead to wasted switch bandwidth.
- Traditional DAC interconnects are too short, thick and bulky to handle high speed ethernet signals between ToR switches and multiple racks.
Smart Electrical Cables (SEC) support longer reach and thinner cabling while adding security and diagnostic capability.
A Taurus Smart Cable Module with gearbox capability can be used on the NIC to resolve the per-lane rate disparity and reduce the end-to-end channel loss, thereby increasing the cable reach and/or reducing cable gauge.
In an average 3m 34 AWG copper wire, the typical channel loss is about 28dB at 12.9GHz, but might be as high as 36dB during worst cases.
Taurus Smart Cable Modules’ advanced fleet management capabilities include Full CMIS Features, Security, and Extensive Diagnostics (Cable Degradation Monitoring, Host-Cable Security, Multiple Loopback Modes, and Pattern Generation/Checking)
Taurus offers various firmware and setting updates to adapt to diverse system topologies, including firmware flexibility, in-field upgrade support, health monitoring and debug, and CMIS extension.
A user can update module management functions, adaption algorithms, and full-module firmware even after the cable is deployed to the switch system.
We offer complete CMIS Firmware update procedures in the product datasheet.
- NRZ is a modulation technique that has two voltage levels to represent logic 0 and logic 1. PAM4 uses four voltage levels to represent four combinations of two bits logic – 11, 10, 01, and 00.
- PAM4 has the advantages of halving the Nyquist frequency and doubling the throughput for the same Baud rate. This alleviates the need for designers to have to invent infrastructure like silicon and cables that would go up to 50GHz bandwidth.
- The SNR loss of a PAM4 signal compared to an NRZ signal is ~9.5 dB.
Have more questions about general topics, such as 800G Ethernet, ordering, quality, etc.? See the full list of FAQs.
Hardware Solutions
Rapidly implement diverse system topologies using our plug-and-play connectivity system boards. Our solutions include:
- CXL Memory Cards: Increase cloud server performance and reduce total cost of ownership through memory expansion, pooling and sharing.
- Smart Cable Modules: Active Copper-Based Solution to Address Reach, Signal Integrity and Bandwidth Utilization Issues for 100G/Lane Ethernet Switch-to-Switch and Switch-to-Server Interconnects.
- Riser Cards: Extend PCIe/CXL technology slots and enable incredibly complex multi-connector topologies.
- PCIe-Over-Cable Extender Cards: Connect a server head-node to a JBoF or JBoG without sacrificing speed.
- GPU Booster Cards: Support external graphics (eGPUs) and enhance the gaming experience.
Services
Rapidly design and achieve signal integrity peace of mind and avoid wondering if a PCIe 4.0/5.0, CXL 1.1/2.0 or 100G/Lane Ethernet technology-based design will work. Our team can help develop first-pass design success and accelerate time to market for your systems and boards.
Contact us for more information about our design and testing services >