Cisco CPAK 100GBASE-SR4 Transceiver

The Cisco CPAK is engineered for high-density optical networks and data centers, delivering robust, scalable 100 Gigabit Ethernet performance in Cisco’s CPAK module form factor. This multi-mode, 100GBASE-SR4 transceiver is designed to maximize efficiency in dense deployments, offering reliable, low-latency connectivity over multimode fiber. Built to meet the rigors of modern data-center ecosystems, the CPAK packaging enables high port density while maintaining Cisco-grade reliability, making it ideal for spine-leaf architectures, campus aggregations, and ambitious enterprise networks that demand fast, consistent throughput.

• 100GBASE-SR4 performance – Harness up to 100 Gbps data transfer over multimode fiber using four parallel 25 Gbps channels. The CPAK module is optimized for high-bandwidth workloads, enabling rapid data transfers between switches, routers, and high-performance servers in dense racks.
• CPA K packaging for dense deployments – The CPAK form factor provides Cisco’s compact, plug-in solution designed for high-density installations. Its streamlined footprint helps maximize rack space utilization while delivering reliable, hot-swappable performance compatible with Cisco optical networks.
• Multi-mode fiber compatibility – Specifically engineered for multi-mode fiber networks, offering strong performance on OM3/OM4 cabling. This makes it an excellent choice for data centers that rely on short-reach, high-capacity links with robust link budgets.
• MPO/MTP connector integration – The SR4 standard uses parallel optics across four lanes, typically leveraging MPO/MTP assemblies for efficient, parallel data transmission. The CPAK module is designed to pair with these connectors to minimize insertion loss and maximize signal integrity.
• Reliability and ease of deployment – Cisco CPAK modules are built for consistent performance in demanding environments. Expect dependable throughput, straightforward installation, and solid long-term support from Cisco’s enterprise-grade ecosystem, suitable for both upgrading existing networks and deploying new 100G fabrics.

Technical Details of Cisco CPAK

• Form Factor: CPAK transceiver module designed for Cisco platforms
• Data Rate: 100GBASE-SR4 with four parallel lanes
• Fiber Type: Multi-mode fiber for short-reach deployments
• Wavelength: 850 nm parallel optical channels
• Connector Type: MPO/MTP compatible interface for MPO-based fiber assemblies
• Operating Environment: Designed for standard data-center ambient conditions with Cisco-grade reliability

how to install Cisco CPAK

• Power down the host device and disconnect any active fiber links to begin installation in a maintenance window, ensuring proper electrostatic discharge (ESD) precautions are followed.
• Identify the correct CPAK slot on the Cisco device and verify compatibility with 100GBASE-SR4 CPAK modules to prevent mis seating or cross-compatibility issues.
• Gently align the CPAK module with the slot, ensuring the connector interface lines up with the receptacle. Do not apply lateral force; ensure the module seats evenly and the latch engages securely.
• Insert fiber assemblies carefully, keeping fiber paths organized and free of excessive bending. Secure MPO/MTP connectors per your data-center standard, confirming connector cleanliness and proper connector orientation.
• Power on the device and monitor the system console for a successful link status, auto-negotiation results, and fault indications. If needed, perform a quick reset or re-seat the module to confirm stability.
• Verify operational health with the device’s management interface: check interface status, error counters, and throughput tests. Confirm the link is up at the expected speed and that the remote end is reachable with the intended bandwidth.

Frequently asked questions

• What is Cisco CPAK used for? The Cisco CPAK is a high-density 100GBASE-SR4 transceiver designed for optical networks and data-center deployments, enabling 100 Gbps links over multimode fiber with a compact, Cisco-packaged form factor.
• Which fiber type do I need? For 100GBASE-SR4 CPAK modules, multimode fiber (MMF) is typically used, particularly OM3 or OM4 cabling, to support the parallel SR4 channels while maintaining a reliable link budget.
• How do I know if my switch supports CPAK? Check Cisco device compatibility lists to ensure your switch or router model accepts CPAK modules, and verify the module’s firmware compatibility with your device’s IOS/NX-OS version.
• What maintenance considerations apply? Regularly inspect fiber connectors for cleanliness, use proper polarity when installing MPO/MTP assemblies, and monitor link performance. Cisco-grade reliability also benefits from keeping equipment firmware up to date.
• Can I mix CPAK with other 100GBASE-SR4 modules? It depends on the platform and fabric design; for optimal performance, use CPAK modules within supported Cisco systems and follow vendor guidelines for homogeneous module usage within the same line card or fabric.
• What is the typical deployment scenario? 100GBASE-SR4 CPAK modules are commonly used in data-center spine-leaf fabrics and high-density aggregation layers where multiple parallel 25G channels must be aggregated into a single 100 Gbps link over short-reach multimode fiber.