CFP Wiki：CFP /CFP2/CFP4 Transceiver Module Overview

Serving as the mainstream high-speed transport technology, 40/100G is the choice of data center to underlines the bandwidth bottlenecks facing high traffic service. Thus CFP transceiver is introduced at the point to meet those requirements. This article offers a simple CFP wiki, addressing rudiments of CFP /CFP2/CFP4 transceiver module. Let’s see how data centers could benefit from adopting CFP transceiver.

CFP Wiki: The Choice of Data Center

The CFP MSA (Multi-Source Agreement) defines hot-pluggable optical transceiver form factors to enable 40/100G and the looming 400G applications. It includes pluggable CFP, CFP2 and CFP4 transceivers to support the high bandwidth requirements of data communication networks. Compared with CFP form factor, the latter CFP2 and CFP4 module are of smaller size, and will double and quadruple front panel port density, respectively. CFP 2 and CFP4 modules support existing and future duplex single-mode fiber (SMF) and multimode fiber (MMF) interfaces. The figure below shows drawings of the CFP, CFP2, and CFP4 form factors. Let’s go further to have a detailed understanding of each.

CFP Transceiver Module

CFP (C=100 in Roman numerals; Centum) refers to 100G form-factor pluggable, which is a new ultra high speed pluggable I/O interface supporting 40 and 100G Ethernet applications. CFP transceiver is defined by MSA (Multi-Source Agreement) for high-speed digital signal transmission, like carrier networks, data centers and wireless equipment. The original CFP specification was proposed at a time when 10 G signals were far more achievable than 25 G signals. As such to achieve 100 Gbit/s line rate, the most affordable solution was based on 10 lanes of 10 Gbit/s.

CFP2 Transceiver Module

Advances in technology have brought about CFP2 MSA. CFP2 module specifies a form-factor of 1/2 in size of the CFP module. The CFP2 module electrical interface varies by application, but the nominal signaling lane rate is 25Gbit/s per lane. Its interface can also optionally support a nominal signaling lane rate of 10Gbit/s. CFP2 module may be used to support single-mode fiber (SMF) and multimode fiber (MMF). Designed for optical networking, the size of CFP2 module has been chosen to accommodate a wide range of power dissipations and applications. The module electrical interface has been generically specified to allow for supplier-specific customization around various 4 x 25Gbit/s interfaces, but can support 8x25Gbit/s, 10x10Gbit/s, and 8x50Gbit/s.

CFP4 Transceiver Module

Then here comes the latest CFP4 hot-pluggable transceiver module. CFP MSA defined the CFP4 form factor as an optical transceiver to support 40/100G interface for Ethernet, Telecommunication and other applications. Identical to CFP2 module, the electrical interface of CFP4 will vary by application, the nominal signaling lane rate is also 25Gbit/s. The CFP4 electrical interface can also optionally support a nominal signaling lane rate of 10Gbit/s. With 1/4 the size of CFP module, CFP4 can be used to support SMF and MMF optics. CFP4 electrical interface is specified to allow for customization specified by supplier with various 4 x 25Gbit/s and 4 x 10Gbit/s interfaces.

Summary

CFP, CFP2 and CFP4 are 100G hot-pluggable form factors that designed for optical communication applications compliant to 40/100G IEEE 802.3 standard. Which is a great fit for 40 and 100G Ethernet data center applications. CFP2 and CFP4, with smaller size and 2.8 times faster speed than current CFP module, enables higher network density and more design flexibility. This article only provides CFP wiki and some basic information of CFP, CFP2 and CFP4, wish it can help.

QSFP28 MSA Compatible 100G Optics Overview

As data centers around the world explore their options for increasing network speeds and bandwidth, 100G QSFP28 MSA compatible optics appear as an ideal alternative to accelerate data flow. QSFP28 optics hence become the universal data center form factor for 100G network transmission. This article will address QSFP28 MSA compatible optics used in 100G transmission.

QSFP28 MSA Optics: The Revolution in Data Centers

The adoption rate of QSFP28 MSA compliant optics is consistently on the rise for the past few years. It is predicted that over half of the data center will make the shift to adopting optics that is QSFP28 MSA compliant. The traditional 10G or even 40G may not be enough considering the explosion of data, therefore, QSFP28 MSA is going to become the new standard, and it has the following advantages.

Cost Efficiency—QSFP28 MSA optics now deliver a compelling price point, offering far greater capacity increases. And it still future-proofing the network with unsurpassed bandwidth. The growth in QSFP28 MSA optic deployments will undoubtedly drive down the cost of 100G optics.

Speed and Capacity—SFP+ and QSFP+ optics will not be enough for data intensive industries. Thus QSFP28 MSA optic is specifically designed to transport enormous amounts of data with ultra-low latency.

Flexibility—100G will be the preferred technology across long-haul networks. 100G networking can be customized, optimized, and easily expanded to allow for changes in the future.

QSFP28 MSA Compatible Optics Overview

QSFP28 MSA optic generally has the exact same footprint and faceplate density as 40G QSFP+ . But it is implemented with four 25-Gbps lanes. With an upgrade electrical interface, QSFP28 MSA optic is capable of supporting signal up to 28Gbps signals. Though QSFP28 transceiver keeps all of the physical dimensions of its predecessors, it surpasses them with the strong ability to increase density, decrease power consumption, and decrease price per bit. The Following are some QSFP28 MSA compliant optics for different applications.

100G SR4 QSFP28

100G SR4 QSFP28 is designed to support short distance transmission via multimode fiber. This transceiver module can support 100G transmission up to 70m on OM3 MMF and 100m on OM4 MMF. With MTP interface, the 100G SR4 QSFP28 MSA complaint module enables 4×25G dual way transmission over 8 fibers.

100G QSFP28 LR4

100G QSFP28 LR4 is QSFP28 MSA complaint, and is specifically designed for use in long distance transmission. QSFP28 LR4 utilizes WDM technology for 4×25G data transmission, and these four 25G optical signals are transmitted over four different wavelengths. With a duplex LC interface, 100G LR4 QSFP28 module enables 100G dual-way transmission up to 10 km over single-mode fiber.

QSFP28 100G PSM4

100G PSM4 is standardized by QSFP28 MSA and it uses four parallel fibers (lanes) operating in each direction, with each lane carrying a 25G optical transmission. 100G PSM4 module sends the signal down to eight-fiber cable with an MTP interface. The operating distance of 100G PSM4 is limited to 500 m.

QSFP28 100G DWDM4

100G DWDM4 uses WDM technology—an optical multiplexer and de-multiplexer to reduce the number of fibers to 2. Being QSFP28 MSA compatible, 100G DWDM4 can operate on single-mode fiber up to 2 km over duplex LC interface. Compared with QSFP28 LR4, it has shorter transmission distance and lower cost.

QSFP28 MSA Compliant Cables

In addition to the all the QSFP28 MSA 100G transceivers mentioned above, there are also high-speed cables deployed in 100G network. The cables can be either QSFP28 to 4 SFP28 copper cables (DACs), or active optical cables (AOCs). QSFP28 to 4 SFP28 DACs offer the lowest cost with reach up to 3 m. They are typically used within the racks of the data center, or as chassis-to-chassis interconnect in large switch and routers. QSFP28 AOCs are much lighter and offer longer reach up to over 100 m.

Conclusion

QSFP28 MSA compliant 100G optics are indispensable component to embrace 100G to your infrastructure, and they also facilitate scaling to 100G networks with the simplicity as 10G. With higher port density, lower power consumption and lower cost, QSFP28 MSA transceiver is an ideal alternative for large scale data centers, as well as for future network expansions.

Use 100G QSFP28 Transceiver to Speed Up Your Network

The unceasing migration to higher levels of network performance and scalability drives the boom of 100G transceiver market. 100G transceiver has become a preferable alternative for those bandwidth-hungry applications to accelerate data flow in data centers. In this article, we will introduce several types of 100G transceiver which are commonly seen on the market. And emphasis will be put on the 100G QSFP28 transceiver.

Common 100G Transceiver Decoding

Currently, we have 100G CFP transceiver, CFP2 transceiver and CFP4 transceiver available on the market. The CFP transceiver comes out firstly. It was designed just after SFP interface, but it is significantly larger to support 100 Gbit/s data rates. While the electrical connection of a CFP transceiver uses 10 x 10 Gbit/s lanes in each direction (RX, TX), the optical connection can support both 10 x 10 Gbit/s and 4 x 25 Gbit/s variants of 100 Gbit/s interconnects.

As technology keeps advancing, there came CFP2 and CFP4 that allows higher performance and density. Having similar electrical connection with a CFP transceiver, CFP2 and CFP4 transceiver specify a form-factor of 1/2 and 1/4 respectively in size of a CFP transceiver. These three modules are not interchangeable, but would be inter-operable at the optical interface with appropriate connectors.

100G QSFP28 transceiver Description

Then here comes the dominate 100G transceiver—100G QSFP28 transceiver, supporting four 25 Gbit/s lanes. With an upgraded electrical interface, 100G QSFP28 transceiver is capable of handling signal rates up to 28 Gbit/s, making 100G network deployment as easy as that of 10G. Moreover, 100G QSFP28 transceiver has a strong ability to increase density, decrease power consumption, and decrease price per bit.

Thanks to QSFP28 module, the path to 100G can hence be changed from 10G-40G-100G to 10G-25G-100G or 10G-25G-50G-100G, with largely simplified cabling and reduced costs. There are two widely used 100G QSFP28 transceiver: QSFP28 100G SR4 for short range transmission up to 100 m and QSFP28 100G LR4 for long range transmission up to 10 km. The following diagram illustrate the details of each QSFP28 module.

What to Benefit From 100G QSFP28 transceiver?

Giving a look back to the evolution of 100G transceiver, all these changes are closely related to factors like power and cost – makes the prevalence of 100G QSFP28 transceiver an inevitable trend. Then, what exactly can QSFP28 module bring to us?

Higher Port Density: The first generation of 100G transceiver is CFP, which is very large. When it comes to CFP2 and CFP4, the size was a lot decreased. With the same footprint and face plate density as QSFP+, QSFP28 module is even smaller than CFP4, and its high port density is also an overwhelming advantage. Generally, up to 36 QSFP28 can be installed on a 1RU switch on the front panel.

Lower Power Consumption: Compared with other 100G transceiver, QSFP28 transceiver requires the lowest power for transmission, with less than 3.5 Watts. While for other 100G transceiver, the power consumption ranges from 6 Watts to 24 Watts.

Lower Cost: QSFP28 transceiver is able to save considerable amount of money with higher port density and lower power consumption. While implemented with four lanes, 100G QSFP28 transceiver increases the transmission capacity of every lane from 10G to 25G, which effectively decreases the cost for each bit.

Conclusion

With higher port density, lower power consumption and lower cost, 100G QSFP28 transceiver offers an optimum and feasible alternative for 100G network, especially for those large scale data centers and carriers. Hope this article could assist you in choosing the right transceiver to achieve smooth 100G migration.