Overview
The 100G CFP4 optical transceiver is a high-performance module designed for 100Gbps Ethernet and telecommunication applications. As the fourth generation in the CFP (C Form-factor Pluggable) family, the CFP4 module offers the same 100G data rate as its CFP and CFP2 predecessors but in a significantly more compact package. This smaller footprint, which is similar in width to the QSFP28, allows for much higher port density on line cards and switches, making it a critical component for scaling network capacity in service provider and core network environments.
Adhering to the CFP4 MSA (Multi-Source Agreement), these modules ensure interoperability and are engineered for long-reach applications, with popular variants like 100GBASE-LR4 for 10km and 100GBASE-ER4 for 40km links over single-mode fiber.
Key Features
- Compact Form Factor: Offers a significant size reduction compared to CFP and CFP2, enabling higher front-panel port density.
- Long-Reach Variants: Primarily available in LR4 (10km) and ER4 (40km) versions, ideal for metro, regional, and long-haul networks.
- 4x25G Architecture: Operates on four parallel 25Gbps LAN-WDM optical lanes to achieve an aggregate data rate of 100Gbps.
- Hot-Pluggable: Allows for installation or replacement of modules without shutting down the host system, ensuring network uptime.
- Low Power Consumption: Features lower power consumption than the earlier CFP and CFP2 generations, leading to reduced operational costs.
- Digital Diagnostics (DDM): Includes Digital Diagnostics Monitoring (DDM/DOM) capabilities for real-time monitoring of key operational parameters.
Applications
The 100G CFP4 transceiver is specifically targeted at high-capacity, long-distance networking. Its primary applications include service provider core networks, metro Ethernet deployments, and data center interconnects (DCI) that span longer distances. It is also commonly used in 100G OTN (Optical Transport Network) client-side interfaces and in core routers and high-density switches that require long-reach 100G connectivity.
Specifications
| Parameter | Value |
|---|---|
| Form Factor | CFP4 |
| Data Rate | 103.1 Gbps to 112 Gbps |
| Common Variants | 100GBASE-LR4, 100GBASE-ER4 |
| Maximum Reach | 10km (LR4), 40km (ER4) |
| Wavelengths (LAN-WDM) | 1295nm, 1300nm, 1304nm, 1309nm |
| Fiber Type | Single-Mode Fiber (SMF) G.652 |
| Connector Type | Duplex LC |
| Compliance | CFP4 MSA, IEEE 802.3ba |
Advantages
The main advantage of the 100G CFP4 module is its balance of performance, reach, and density. Compared to the original CFP, the CFP4 is drastically smaller, allowing network operators to quadruple their port density for 100G links. This is crucial for expanding network capacity without requiring a complete overhaul of the existing chassis.
While the QSFP28 form factor became dominant in short-reach data center applications due to its even smaller size, the CFP4 found its niche in service provider networks where longer reaches like 40km (ER4) were a primary requirement. The CFP4’s slightly larger size and power envelope were better suited to the more complex optics needed for these demanding long-haul applications.
FAQ (Technical & product category Questions)
1. What is a 100G CFP4 module?
A 100G CFP4 is a hot-pluggable optical transceiver for 100Gbps data links. It is the fourth generation of the CFP form factor, designed to be much more compact than CFP/CFP2, thus allowing for higher port density on network equipment.
2. What is the difference between CFP, CFP2, and CFP4?
The primary difference is physical size and power consumption. Each generation is progressively smaller: CFP is the largest, followed by CFP2 (half the size of CFP), and then CFP4 (about half the size of CFP2). This size reduction allows for increased port density on the host device. Power consumption also typically decreases with each smaller generation.
3. How does a CFP4 compare to a QSFP28?
Both are 100G transceivers. The QSFP28 is even smaller than the CFP4 and has become the standard for 100G in data centers due to its high density and low power. The CFP4 is slightly larger and was more commonly adopted in service provider and telecommunication networks, especially for longer reach applications like ER4 (40km), which require more power and complex optics.
4. What do LR4 and ER4 mean for a CFP4 module?
LR4 and ER4 specify the reach and application. CFP4 LR4 (Long Reach) is designed for links up to 10 kilometers. CFP4 ER4 (Extended Reach) is designed for much longer links up to 40 kilometers. Both use four LAN-WDM wavelengths over single-mode fiber.
5. What kind of cable is used with a 100G CFP4 LR4/ER4?
Both 100G CFP4 LR4 and ER4 modules use a standard duplex single-mode fiber patch cable with LC connectors.
6. Can I plug a CFP4 module into a CFP2 port?
No. Although they are part of the same family, the form factors are different. A CFP4 module will not physically fit into a CFP2 or CFP port. You must match the module’s form factor to the port on your switch or router.
7. Is the 100G CFP4 still relevant today?
While QSFP28 is the dominant form factor for new 100G deployments, especially in data centers, the 100G CFP4 is still widely used in existing service provider networks and carrier equipment. It remains a relevant and necessary component for maintaining and expanding these specific network infrastructures.