Category Archives: Fiber Optical Transceivers

400G ZR & ZR+ – New Generation of Solutions for Longer-reach Optical Communications

400G ZR and ZR+ coherent pluggable optics have become new solutions for high-density networks with data rates from 100G to 400G featuring low power and small space. Let’s see how the latest generation of 400G ZR and 400G ZR+ optics extends the economic benefits to meet the requirements of network operators, maximizes fiber utilization, and reduces the cost of data transport.

400G ZR & ZR+: Definitions

What Is 400G ZR?

400G ZR coherent optical modules are compliant with the OIF-400ZR standard, ensuring industry-wide interoperability. They provide 400Gbps of optical bandwidth over a single optical wavelength using DWDM (dense wavelength division multiplexing) and higher-order modulation such as 16 QAM. Implemented predominantly in the QSFP-DD form factor, 400G ZR will serve the specific requirement for massively parallel data center interconnect of 400GbE with distances of 80-120km. To learn more about 400G transceivers: How Many 400G Transceiver Types Are in the Market?

Overview of 400G ZR+

ZR+ is a range of coherent pluggable solutions with line capacities up to 400Gbps and reaches well beyond 80km supporting various application requirements. The specific operational and performance requirements of different applications will determine what types of 400G ZR+ coherent plugs will be used in networks. Some applications will take advantage of interoperable, multi-vendor ecosystems defined by standards body or MSA specifications and others will rely on the maximum performance achievable in the constraints of a pluggable module package. Four categories of 400G ZR+ applications will be explained in the following part.

400G ZR & ZR+: Applications

400G ZR – Application Scenario

The arrival of 400G ZR modules has ushered in a new era of DWDM technology marked by open, standards based, and pluggable DWDM optics, enabling true IP-over-DWDM. 400G ZR is often applied for point-to-point DCI (up to 80km), making the task of interconnecting data centers as simple as connecting switches inside a data center (as shown below).

Figure 1: 400G ZR Applied in Single-span DCI

Four Primary Deployment Applications for 400G ZR+

Extended-reach P2P Packet

One definition of ZR+ is a straightforward extension of 400G ZR transcoded mappings of Ethernet with a higher performance FEC to support longer reaches. In this case, 400G ZR+ modules are narrowly defined as supporting a single-carrier 400Gbps optical line rate and transporting 400GbE, 2x 200GbE or 4x 100GbE client signals for point-to-point reaches (up to around 500km). This solution is specifically dedicated to packet transport applications and destined for router platforms.

Multi-span Metro OTN

Another definition of ZR+ is the inclusion of support for OTN, such as client mapping and multiplexing into FlexO interfaces. This coherent pluggable solution is intended to support the additional requirements of OTN networks, carry both Ethernet and OTN clients, and address transport in multi-span ROADM networks. This category of 400G ZR+ is required where demarcation is important to operators, and is destined primarily for multi-span metro ROADM networks.

Figure 2: 400G ZR+ Applied in Multi-span Metro OTN

Multi-span Metro Packet

The third definition of ZR+ is support for extended reach Ethernet or packet transcoded solution that is further optimized for critical performance such as latency. This 400G ZR+ coherent pluggable with high performance FEC and sophisticated coding algorithms supports the longest reach over 1000km multi-span metro packet transport.

Figure 3: 400G ZR+ Applied in Multi-span Metro Packet

Multi-span Metro Regional OTN

The fourth definition of ZR+ supports both Ethernet and OTN clients. This coherent pluggable also leverages high performance FEC and PCS, along with tunable optical filters and amplifiers for maximum reach. It supports a rich feature set of OTN network functions for deployment over both fixed and flex-grid line systems. This category of 400G ZR+ provides solutions with higher performance to address a much wider range of metro/regional packet networking requirements.

400G ZR & ZR+: What Makes Them Suitable for Longer-reach Transmission in Data Center?

Coherent Technology Adopted by 400G ZR & ZR+

Coherent technology uses the three degrees of freedom (amplitude, phase and polarization of light) to focus more data on the wave that is being transmitted. In this way, coherent optics can transport more data over a single fiber for greater distances using higher order modulation techniques, which results in better spectral efficiency. 400G ZR and ZR+ is a leap forward in the application of coherent technology. With higher-order modulation and DWDM unlocking high bandwidth, 400G ZR and ZR+ modules can reduce cost and complexity for high-level data center interconnects.

Importance of 400G ZR & ZR+

400G ZR and 400G ZR+ coherent pluggable optics take implementation challenges to the next level by adding some of the elements for high-performance solutions while pushing component design for low-power, pluggability, and modularity.

Conclusion

Although there are still many challenges to making 400G ZR and 400G ZR+ transceiver modules that fit into the small size and power budget of OSFP or QSFP-DD packages and also achieving interoperation as well the costs and volume targets. With 400Gbps high optical bandwidth and low power consumption, 400G ZR & ZR+ may very well be the new generation in longer-reach optical communications.

Original Source: 400G ZR & ZR+ – New Generation of Solutions for Longer-reach Optical Communications

400G OSFP Transceiver Types Overview

OSFP stands for Octal Small Form-factor Pluggable, which consists of 8 electrical lanes, running at 50Gb/s each, for a total of the bandwidth of 400Gb/s. This post will give an introduction of 400G OSFP transceiver types, the fiber connections, and some QAs about OSFP.

400G OSFP Transceiver Types

Below lists some current main 400G OSFP transceiver types: OSFP SR8, OSFP DR4, OSFP DR4+, OSFP FR4, OSFP 2*FR4, and OSFP LR4, which summarize OSFP transceiver according to the two transmission types (over multimode fiber and single-mode fiber) they support.

Fibers Connections for 400G OSFP Transceivers

400G OSFP SR8

Connect a 400G OSFP SR8 transceiver with another 400G OSFP SR8 transceiver over an MTP-16/MPO-16 cable.

400G OSFP SR8 to 2× 200G SR4 over MTP-16 to 2× MPO-8 breakout cable.

400G OSFP SR8 to 8× 50G SFP via MTP-16 to 8× LC duplex breakout cable with up to 100m.

400G OSFP DR4

400G OSFP DR4 to 400G OSFP DR4 over an MTP-12/MPO-12 cable.
400G OSFP DR4 to 4× 100G DR4 over MTP-12/MPO-12 to 4× LC duplex breakout cable.

400G OSFP XDR4/DR4+

400G OSFP DR4+ to 400G OSFP DR4+ over an MTP-12/MPO-12 cable.
400G OSFP DR4+ to 4× 100G DR over MTP-12/MPO-12 to 4× LC duplex breakout cable.

400G OSFP FR4

400G OSFP FR4 to 400G OSFP FR4 over duplex LC cable.

400G OSFP 2FR4

OSFP 2FR4 can break out to 2× 200G and interop with 2× 200G-FR4 QSFP transceivers via 2× CS to 2× LC duplex cable.

400G OSFP Transceivers: Q&A

Q: What does “SR8”, “DR4”, “XDR4”, “FR4”, and “LR4” mean?

A: “SR” refers to short range, and “8” implies there are 8 optical channels. “DR” refers to 500m reach using single-mode fiber, and “4” implies there are 4 optical channels. “XDR4” is short for “eXtended reach DR4”. And “LR” refers to 10km reach using single-mode fiber.

Q: Can I plug an OSFP transceiver module into a QSFP-DD port?

A: No. QSFP-DD and OSFP are totally different form factors. For more information about QSFP-DD transceivers, you can refer to 400G QSFP-DD Transceiver Types Overview. You can use only one kind of form factor in the corresponding system. E.g., if you have an OSFP system, OSFP transceivers and cables must be used.

Q: Can I plug a 100G QSFP28 module into an OSFP port?

A: Yes. A QSFP28 module can be inserted into an OSFP port but with an adapter. When using a QSFP28 module in an OSFP port, the OSFP port must be configured for a data rate of 100G instead of 400G.

Q: What other breakout options are possible apart from using OSFP modules mentioned above?

A: OSFP 400G DACs & AOCs are possible for breakout 400G connections. See 400G Direct Attach Cables (DAC & AOC) Overview for more information about 400G DACs & AOCs.

Original Source: 400G OSFP Transceiver Types Overview

Cisco SFP+ Modules or 3rd Party SFP+ Modules, Which Is Better?

In order to cater to the development of interface technology, SFP+ module has been introduced to provide a perfect solution with high port density and low cost. SFP+ module is an upgrade version of SFP module which stands for a small form-factor pluggable module. There are many different brands of SFP+ on the market, such as Cisco, HP, Juniper, Brocade, FS, etc.. Among these brands, Cisco is favored by most people. However, with the rising of 3rd party vendors, modules produced by the 3rd party have gone popular with their lower price and good quality. But the doubts and praises around them have never stopped. This article will help you compare all aspects of the products and help to choose Cisco SFP+ modules or 3rd party SFP+ modules.

altCisco SFP+ Modules or 3rd Party SFP+ Modules, Which Is Better?

Cisco or 3rd Party SFP+ Modules: What’s the Difference?

As we know, Cisco provides reliable SFP+ modules, while 3rd party also offers various SFP+ modules. So what’s the difference between them?

Performance

The biggest difference between Cisco SFP+ modules or 3rd party SFP+ modules is the manufacturer. In fact, there are only a few qualified manufacturers. They supply all the raw components for all the transceivers on the market. To be honest, Cisco does not produce its own SFP+ modules or SFP fibers. Cisco is known to purchase optical transceivers from its suppliers who code and label for Cisco and then sell the transceivers to consumers. In this way, most 3rd party compatible modules are built and assembled in the same factory as Cisco. Above all, SFP+ modules are produced according to strict standards of MSA (Multi-Source Agreement), which determines the performance of the modules. Therefore, 3rd party SFP+ modules can be as good as Cisco SFP+ modules.

Compatibility

The compatibility of SFP+ modules is controlled by OEM software codes embedded in the transceiver. Cisco SFP+ modules are not encouraged to use in other brands equipment because codes from different vendors might be unmatched. However, a good 3rd party vendor can make multi-coded compatible transceivers that can support different equipment. Taking FS.COM as an example, FS.COM provides a range of SFP+ transceivers that compatible with the mainstream brands on the market, such as Cisco, HP, Juniper, Brocade, Dell, Extreme, H3C, Arista, Huawei, Intel, IBM etc.. The compatibility and durability of the modules are strictly tested and controlled to ensure product reliability. So there is no need to worry that the 3rd party modules you bought will be incompatible with your devices.

Future Demands

As we know that the data center often accommodates tens of thousands of devices. With your network system grows, it’s hard to connect SFP+ modules from different vendors. In this case, the function of 3rd party vendors reveals. 3rd party vendors can provide various compatible SFP+ modules to satisfy all your needs. Whereas Cisco SFP+ modules are not encouraged to use in other brands, even some of its own Cisco switches. Because different Cisco switches have distinct requirements for codes and hardware, you have to buy the specific one. In this case, Cisco modules are not that supportive for your future demands.

Price

It’s not surprising that Cisco SFP+ modules have a higher price over 3rd party SFP+ modules. Take a 10GBASE-SR SFP+ for example, a Cisco 10GBASE-SR SFP+ sells for $691, but a 3rd party vendor FS.COM sells the same product just for $16. Unbelievable, right? It’s not reasonable for consumers to pay extra money just for a brand logo.

Why Are Cisco SFP+ Modules More Expensive?

If the SFP+ modules are the same, why is a Cisco SFP+ module more expensive than a 3rd party one? There are two main reasons for that. The first reason is that Cisco claims that it has a higher quality than others and it has tested every SFP+ module to ensure the performance. But actually many transceiver manufacturers can do the test now. The other reason is the brand effect. It takes a cost to build a brand, but the benefits brought by the brand is also obvious. Cisco is a large equipment manufacturer with its own unique brand advantages, known by a number of consumers. It makes sense that Cisco has higher product prices.

Is the Quality of 3rd Party Guaranteed?

Certainly. The optical transceiver module is standardized by SFP MSA, which means there is no big difference between Cisco and 3rd party optical transceivers due to the same rules and standards. In addition, if the equipment is defective, the supplier is obliged to fulfill the warranty. The 3rd party has a comprehensive warranty policy to provide technical support and protection to consumers. Although Cisco claims that adding 3rd party modules does not void the warranty unless problems are caused by 3rd party modules. In general, it’s unlikely that SFP+ modules will induce damages to the slot itself. The statement sounds more like a self-interest protection.

Conclusion

Excellent 3rd party vendors have proved themselves with good quality and reputation over the years. If you have found a reliable 3rd party vendor, choosing between high price Cisco SFP+ modules and cost-effective 3rd party SFP+ modules is not difficult. FS.COM is a professional optical transceiver manufacturer that provides a full selection of major brands’ compatible transceiver modules with strict tests and high quality. Along with the support of large inventory and efficient delivery, FS.COM can certainly meet the needs of your network.

Cisco Single Mode SFP VS Cisco Multimode SFP

SFP (shorts for Small Form-Factor Pluggable) is a compact, hot-pluggable transceiver used for both telecommunication and data communications applications. It interfaces to motherboard, router, switch or optical media converter. There are two types of SFP, single mode SFP and multimode SFP. And this articles will focus on Cisco SFP and make a comparison of Cisco single mode SFP and Cisco multimode SFP.

alt Cisco Single Mode SFP

What Is Cisco Single Mode SFP?

Cisco single mode SFP works over single mode fiber whose typical core diameter is 9µm. And the cladding diameter of a single mode fiber is 125µm. Cisco single mode SFP operates mainly at 1310nm and 1550nm wavelengths and is used in long-haul transmission environments of 2km, 10km, 40km, 60km, 80km, and 120km. Cisco single mode SFP consists of 1000BASE-EX SFP, 1000BASE-ZX SFP, 1000BASE-BX10-D SFP, 1000BASE-BX10-U SFP, and 1000BASE-LX/LH SFP. For detailed information, please check the chart below.

Cisco Single Mode SFP	Part Number	Description
1000BASE-EX SFP	GLC-EX-SMD	Operates on single mode fiber over a wavelength of 1310nm for 40km
1000BASE-EX SFP	GLC-EX-SM1550-40	operates on single mode fiber over a wavelength of 1550nm for 40km
1000BASE-ZX SFP	GLC-ZX-SM/GLC-ZX-SMD/GLC-ZX-SM-RGD	Operates on single mode fiber over a wavelength of 1550nm for 80km
1000BASE-BX10-D SFP	GLC-BX-10D	Operates on single mode fiber over a wavelength of 1550nm for 10km
1000BASE-BX10-U SFP	GLC-BX-10U	Operates on single mode fiber over a wavelength of 1310nm for 10km
1000BASE-LX/LH SFP	GLC-LX-SM-RGD/GLC-LH-SM/GLC-LH-SMD	Operates on single mode fiber over a wavelength of 1310nm for 10km
1000BASE-LX/LH SFP	GLC-LH-SM-20	Operates on single mode fiber over a wavelength of 1310nm for 20km

What Is Cisco Multimode SFP?

Cisco multimode SFP works over multimode fiber with the core diameter of 50 µm and 62.5 µm, and the cladding diameter is 125µm as well. The common multimode SFP operates at 850nm wavelength and is only used for short distance transmission of 100m and 500m. For detailed information, please check the chart below.

Cisco Single Mode SFP	Part Number	Description
1000BASE-SX SFP	GLC-SX-MMD/GLC-SX-MM-RGD/GLC-SX-MM	Operates on multimode fiber over a wavelength of 850nm for 550m
1000BASE-LX/LH SFP	SFP-GE-L/GLC-LX-SM-RGD/GLC-LH-SM/GLC-LH-SMD	Operates on multimode fiber over a wavelength of 1310nm for 550m

Cisco Single Mode SFP VS Cisco Multimode SFP

Cisco single mode and multimode SFP modules can both server for transmitting and receiving optical signals and facilitate communication. However, the differences between them are also apparent. Here we will compare them from several aspects.

Connected Fibers

Cisco single mode SFP will work with single mode fiber in order to perform both transmission and reception of data. Whereas Cisco multimode SFP will work with multimode fiber to provide higher speed at shorter distance.

Transmission Distance

Cisco single mode SFP can support distance value as high as 80km or even 120km and mostly used in long distances (up to 10km) transmission environment. Whereas Cisco multimode SFP supports distance up to 550m, more used in a small area or within the building.

Supported Wavelength

Cisco single mode SFP works mainly on 1310nm and 1550nm wavelength, while Cisco multimode SFP works mainly on 850nm wavelength.

Preferential Usage

Cisco single mode SFP is mostly required on WAN connectivity. Whereas Cisco multimode SFP is used inside LAN for the switch, router and server connectivity inside building or data center.

Cost

Generally speaking, Cisco single mode SFP is costly and Cisco multimode SFP is cheaper. That’s because Cisco single mode SFP requires a laser source for transmission and it typically uses a laser diode (LD) as the light source, which is expensive. While Cisco multimode SFP uses a light emitting diode (LED) as the light source.

Conclusion

Now we learn a lot about Cisco single mode SFP and multimode SFP. Before you choose the SFP transceiver, you have to confirm the transmission distance and the wavelength you need and also the cables you already have. Remember that single mode and multimode are not interchangeable. So you have to take into account your actual situation and budget. To save more, you can choose a compatible transceiver module from FS.COM to match all your devices without sacrificing any quality or reliability but only at a lower cost. FS.COM offers various SFPs with a great offer that may be a good choice for you.

Things to Know About SFP+ DAC

Over the years, network cabling has undergone profound changes. 10GbE has successfully extended its coverage from enterprise data centers to medium network market. As the demands increase, it’s important to find an optimized solution for 10GbE applications. In this case, SFP+ DAC serves as a good option. This post will introduce basic information about SFP+ DAC.

What Is SFP+ DAC?

SFP+ DAC (direct attach cable), also named SFP+ DAC twinax cable or SFP+ direct attach copper cable, is a fixed assembly with a fixed length, and the SFP+ connector modules permanently attaches to each end of the cable. By connecting two SFP+ slots directly, SFP+ DAC effectively eliminates the costly optical transceivers required by the device and significantly reduces power consumption, latency, and installation time. Meanwhile, it uses an enhanced SFP+ connector to send data up to 10Gbps through a pair of transmitters and receivers over a thin twinax cable. Thus SFP+ DAC has become an optimized choice for modern short-range, high-speed 10 Gigabit Ethernet applications.

SFP+ DAC

Types of SFP+ DAC

SFP+ DAC comes to two different types: passive SFP+ DAC and active SFP+ DAC.

Passive SFP+ DAC

Passive SFP+ DAC contains no electrical components, thus it requires little to no direct power to operate. So the host networking device must support the signal processing functions. When a SFP+ is inserted, networking gear compatible with passive SFP+ DAC reads the module type, and the signal conditioning is activated only when a passive SFP+ DAC is detected. Passive SFP+ DAC can afford the length ranging from 0.5m to7m, but it’s more susceptible to degradation due to attenuation and crosstalk.

Active SFP+ DAC

Active SFP+ DAC needs DC power to integrate signal processing circuitry into its built-in connectors. That’s one of the reasons why active SFP+ DAC is usually more expensive than passive SFP+ DAC. Active SFP+ DAC has a silicon chip to improve the performance of the cable. It allows cables to be smaller, thinner, longer, and transmit data faster. It affords the length ranging over 7m.

Passive SFP+ DAC vs Active SFP+ DAC

Passive SFP+ DAC Benefits

It has a lower cost and higher reliability.
It has fewer components (No Active Tx /Rx Components) and only has capacitors, resistors, EEPROM and cable.

Active SFP+ DAC Benefits

It improves signal integrity and allows longer cable lengths.
It provides Transmit Pre-emphasis and Active/Adaptive Receive Equalization.
It allows no worries about host Tx/Rx for Cu cables

From the above, we can come to the conclusion that passive SFP+ DAC is much less expensive but requires the host to do the work of driving it properly, while active SFP+ DAC offers added benefits but cost a lot. When the distance is no more than 7m, passive SFP+ DAC is recommended. As for link distance is beyond 7m, active SFP+ DAC would be required.

Conclusion

SFP+ DAC is a cost-effective option to traditional fiber and twisted-pair copper cables in data center deployments. It can provide better performance for high-density deployments and improve electrical characteristics for the most reliable signal transmission. It’s typically used for connections between in-rack and inter-rack. So if you are looking for one, FS.COM offers various of high quality SFP+ DAC with different lengths. And we also offer customized services to meet your special needs. If you’re interested, please contact us at FS.COM.

Getting to Know the DWDM Transceivers in DWDM Systems

To keep pace with the rapid growth of Internet traffic, service providers have been seeking to improve fiber capacity and wavelength spectrum efficiency in their networks. In response to this situation, DWDM technology is emerging. DWDW is an optical multiplexing technique for increasing the bandwidth of existing fiber networks. DWDM transceivers are important parts of DWDM network, which provide high-capacity and long-distance transmissions. Let’s take a closer look together.

dwdm transceivers

What are DWDM and DWDM Transceiver?

DWDM refers to dense wavelength division multiplexing, which is a technology that gathers data signals from different sources, enables them to share a single optical fiber pair while the separation of data streams is ensured. It supports up to 80 simultaneous wavelength channels, with each of the channels only 0.8nm apart. The technology creates multiple virtual fibers thus multiplies the capacity of the physical fiber cable. It is applied to increase bandwidth over existing fiber networks and transmit data for longer distances.

DWDM transceiver is a kind of fiber optic transceiver with its own features and functions. It is designed for single-mode fiber transmission and operates at a nominal DWDM wavelength from 1528.38 to 1563.86 nm (Channel 17 to Channel 61) as specified by the ITU-T. Like other transceivers, it converts the electrical signal to optical signal and vice versa. The transceiver can support up to 10 Gbps and span a distance up to 120 km, which makes itself stand out in high-capacity and long-distance transmissions.

Types of DWDM Transceivers for DWDM Networks

DWDM transceivers are available in different types, which can support transmission rate from 155 Mbit/s to 10 Gbit/s. Here are the common types of DWDM transceivers classified based on data rate, form factor and fixed or tunable wavelength.

From the Perspective of Data Rate

In the case of data rate, DWDM transceiver usually can be divided into two types: 1G DWDM transceiver and 10G DWDM transceiver. 1G DWDM transceiver includes DWDM SFP transceiver. 10G DWDM transceiver can be further divided into DWDM SFP+ transceiver, DWDM X2 transceiver, DWDM XFP transceiver and DWDM XENPAK transceiver. DWDM SFP transceiver provides a signal rate range from 100 Mbps to 2.5 Gbps, usually used as part of a DWDM optical network to provide high-capacity bandwidth. DWDM SFP+/X2/XFP/XENPAK transceivers support 10-Gigabit data rates from 9.9G to 11.25G (LAN, WAN, and OTU2/OTU2e) which are applied in different applications.

From the Perspective of Form Factor

In terms of form factor, DWDM transceiver can be classified into DWDM SFP transceiver, DWDM SFP+ transceiver, DWDM X2 transceiver, DWDM XFP transceiver and DWDM XENPAK transceiver. Among those transceivers, DWDM SFP and SFP+ transceivers are the most commonly used ones, based on the SFP form factor which is an MSA standard build. DWDM X2 transceiver is based on the X2 form factor, designed for high speed data transmission for data center networking. It’s an ideal choice for data communications and telecommunications switches and routers. DWDM XFP transceiver is based on the XFP form factor which is also an MSA standard build. DWDM XENPAK transceiver is SC duplex receptacle module and is designed for backbone Ethernet transmission systems, which is the first 10GbE transceiver that supports DWDM. It can support 32 different channels for transmission distance up to 200 km with the aid of EDFAs.

From the Perspective of Fixed or Tunable Wavelength

Considering fixed or tunable wavelength, DWDM transceiver can be divided into fixed wavelength DWDM transceiver and DWDM tunable transceiver. Fixed wavelength DWDM transceiver, as the name implies, the wavelength is fixed. It can only transmit a certain number of wavelength, regular fixed wavelength transceiver transmits wavelength at 1310nm and 1550nm for 10G data transmission applications. The Tunable DWDM transceiver is a unique product which enables you to set the channel or “color” that the laser emits. Typically these tunable optics are for the C-Band 50GHz. Around 88 different channels can be set with intervals of 0.4nm. Tunable transceivers are typically used as “spare-optics”, in case of emergency.

Conclusion

In DWDM systems, a large number of DWDM transceivers with different wavelengths, data rates and form factors are required to satisfy network flexibility in optical network. Now that you know all the types of DWDM transceivers, you can compare them with each other and find the one you need. FS.COM provides a variety of transceivers including those mentioned above. High-quality and cost-effective products, intimate service only at FS.COM. You won’t want to miss it.

Cisco SFP+ Module Wiki and Buying Tips

When it comes to optical modules, the brand Cisco especially their Cisco SFP+ modules will be mentioned by almost everyone in optic fiber field. As one of the worldwide leaders in IT and networking, Cisco has dedicated to networking equipment design and manufacture for several decades. Among their all sorts of product lines, SFP+ modules have enjoyed a widespread reputation. In the context of that, in this article, we are going to make an overall exploration of the Cisco’s superstar product: Cisco SFP+ module.

Figure 1: Cisco compatible 10G SFP+ modules

An Overview of the Cisco SFP+ Module

Like the general SFP+ transceivers, Cisco SFP+ modules are kinds of optical devices designed for 8 Gbit/s Fibre Channel, 10 Gigabit Ethernet and optical transport network standard OTU2, supporting data rates up to 16 Gbit/s.

Main Features

Main features of Cisco SFP+ modules can be shared as below:

Industry’s smallest 10G form factor for greatest density per chassis
Hot-swappable input/output devices that plug into an Ethernet SFP+ port of a Cisco switch (no need to power down if installing or replacing)
Supports “pay-as-you-populate” model for investment protection and ease of technology migration
Optical interoperability with 10GBASE XENPAK, 10GBASE X2, and 10GBASE XFP interfaces on the same link
Hot-swappable input/output devices that plug into an Ethernet SFP+ port of a Cisco switch (no need to power down if installing or replacing)
Cisco quality identification (ID) feature enables a Cisco platform to identify whether the module is certified and tested by Cisco

Cisco SFP+ Module Types

With various Cisco SFP+ module types, a wide variety of 10 Gigabit Ethernet connectivity options for diverse networking environments, like data centers, enterprise wiring closet, and service provider transport applications can be offered. Altogether, Cisco SFP+ modules consist of Cisco SFP-10G-SR, SFP-10G-LR (LRM), SFP-10G-ER and SFP-10G-ZR, etc. You can refer to the table displayed as below for detailed specifications of Cisco SFP+ modules.

Cisco SFP+	Wavelength (nm)	Interface	Cable Type	Core Size (Microns)	Cable Distance
Cisco SFP-10G-SR-S	850	Dual LC/PC	MMF	62.5	26 m
Cisco SFP-10G-SR					33 m
Cisco SFP-10G-SR-X				50	66/82/300/400 m
Cisco SFP-10G-LRM	1310	Dual LC/PC	SMF/MMF	G.652/62.5/50	300/100/220 m
Cisco SFP-10G-LR-S			SMF	G.652	10 km
Cisco SFP-10G-LR
Cisco SFP-10G-LR-X
Cisco SFP-10G-ER-S	1550	Dual LC/PC	SMF	G.652	40 km
Cisco SFP-10G-ER
Cisco SFP-10G-ZR-S					80 km
Cisco SFP-10G-ZR
Cisco FET-10G	850	Dual LC/PC	MMF	50	25/100 km
Cisco SFP-10G-BXD-I	1330	Dual LC/PC	SMF	G.652	10 km
Cisco SFP-10G-BXU-I	1270
Cisco SFP-10G-BX40D-I	1330				40 km
Cisco SFP-10G-BX40U-I	1270

How to Choose Cisco SFP+ Modules?

If you want to buy Cisco SFP+ modules, it’s sensible to put their optimum transmission distance and compatibility with other Cisco devices into consideration.

As for the transmission distance, basically, the ranges between 100 m to 400 m and 10 km to 80 km are commonly seen. For the distance from 100 m to 400 m, we usually use Cisco 10G multimode SFP+ transceiver. For example, if you want to buy a Cisco SFP+ module for transmission within 300 m, then the Cisco SFP-10G-SR module will be the best choice. More information about the optimum transmission distance of Cisco SFP+ modules, you can refer to the table above.

Apart from distance, another important thing you should be clear about is the SFP+ module’s compatibility with other Cisco devices. You may wonder if this Cisco SFP+ Module can connect with other devices, such as SFP modules. The answer is NO. For example, If you connect the SFP-10G-SR with Cisco GLC-SX-MMD SFP transceiver (1 Gbps only), they may not be able to work. Since the SFP-10G-SR only runs at 10 Gbps link rate, it means you force SFP-10G-SR to use 1Gbps speed. You can never interconnect them. For more details about the compatibility of Cisco modules, you can search it from their online Compatibility Matrix.

Figure 2: Cisco SFP-10G-SR (Right) and Cisco GLC-SX-MMD SFP (Left)

By the way, Cisco SFP+ module price sometimes is also troublesome for many buyers. When you search Cisco SFP+ modules online, you will find the price of these modules from original brand retailers is not economical. Therefore, in recent years, using non-original brand retailers optical transceivers in fiber optic network has been a trend. More and more users prefer third-party modules, like FS.COM, pluggable optics as they are assured to be fully compatible with the original brand hardware as well as having a cheap price.

Conclusion

As a leading role in fiber optic network, Cisco SFP+ module has been witnessed a glorious period. But with the unremitting efforts of other manufacturers, undoubtedly, other non-original brand retailers brands will be seen on the rise. For sure, the FS.COM will be that great case.

Tunable vs Standard DWDM SFP+ Modules

Nowadays, SFP+ modules have been largely applied into use. However, in order to meet people’s demand for greater transmission capacity, the Dense wavelength division multiplexing (DWDM) as a kind of technology, combining multiple data signals on laser beams at various wavelengths and transmitting them over a single optic fiber network is also in urgent need to combine with SFP+ modules. Currently, the tunable DWDM SFP+ modules and the standard DWDM SFP+ are commonly found in the market. In this article, we are going to introduce these two types to you.

What Are the Tunable DWDM SFP+ Modules

At first, let’s go over the SFP+ transceiver definition from SFP+ transceiver wiki. In short, the SFP+ transceiver is the enhanced version of SFP module. It is a compact, hot pluggable optic module transceiver used for telecommunications and data communication applications. (If you want to get more details about how to use SFP+ transceiver, you can refer to the article A Complete Guide of Installing or Removing Transceiver Modules.) There are many types of SFP+ modules, among which the tunable DWDM SFP+ modules is a very important one.

The tunable DWDM SFP+ module can also be called tunable SFP+ transceiver, because it’s only available in DWDM form for its narrower grid than CWDM’s. The tunable DWDM SFP+ module is a unique device which enables you to set the channel or “color” the laser emits. According to the network demand, you can adjust your transmission wavelength unlimitedly within the C-band DWDM ITU Grid.

Figure 1: 10G DWDM C-band Tunable SFP+ Modules

Why Prefer the Tunable DWDM SFP+ Module

Since the standard DWDM SFP+ module is also a popular type in the market, you may still get confused about these two SFP+ types. In fact, the tunable DWDM SFP+ module is more preferred by the user. In the light of that, this part will explore this doubt.

First, the cost will be a major factor. Frankly, in short term, the price of a tunable DWDM SFP+ is much higher than a DWDM SFP+. However, the conventional DWDM SFP+ transceivers use fixed-wavelength lasers as light sources. Hence, for different wavelength channels, you need to use the corresponding optical transceivers to receive and transmit signals. However, a tunable DWDM SFP+ can operate at any channel wavelength for its tunable laser. Moreover, in order to prevent an unexpected breakdown, users have to prepare kinds of DWDM SFP+ modules with different wavelengths for a rainy day. Considering that will be a huge cost for any user, using a tunable DWDM SFP+, things will be quite different. In light of that, from a long term, the tunable DWDM SFP+ will definitely be the best choice to save your cost.

Second, it’s the flexible network management. When a DWDM network runs with lots of nodes, for example, for 80 different wavelengths, their management could be a nightmare. In different locations, you have to prepare couples of DWDM SFP+ optics for each wavelength. Thus tunable DWDM SFP+ would be a good choice. It is configured for a specific wavelength to support bandwidth changes as needed in the optical network.

Figure 2: 10G DWDM SFP+ Modules 100GHz

Conclusion

Through this article, the two special types of transceiver modules in combining with the DWDM technology have been introduced: tunable DWDM SFP+ modules and standard DWDM SFP+ modules. After that, based on a comparison of these two types of modules, reasons contributing to people’s preferred choice of tunable DWDM SFP+ modules have also been explored. Hope it has helped to clear your doubt these two types.

Fiber SFP Module VS Fiber Media Converter

Many devices in the optical communication field are sharing similar functions, such as fiber SFP module and fiber media converter. They are designed as the equipment for photoelectric conversion. Some of you may get confused about the two seemingly similar devices. Don’t worry, in this article, we are going to reveal the secret between SFP fiber module and fiber media converter. In the beginning, let’s go over the definitions of them.

What Is the Fiber SFP Module

The SFP (small form-factor pluggable) module, also called mini GBIC (gigabit interface converter), is a compact, hot-pluggable optical transceiver used for both telecommunication and data communication applications. It converts electrical signals to optical signals and vice versa. Usually, the SFP module consists of optical SFP and copper SFP. And the type depends on whether their SFP ports connect with fiber optic cables or copper cables. The fiber SFP module can support SONET, Gigabit Ethernet, Fiber Channel, and other communication standards.

Figure 1: SFP Copper RJ45 100m Transceiver

What Is Fiber Media Converter?

Similar to the working mode of optical transceivers, the fiber media converter receives data signals from one media and transmits them to another. Conventionally, fiber media converters can support two kinds of conversion: copper-to-fiber and fiber-to-fiber. Copper-to-fiber media converters are devices designed to connect two dissimilar media types, such as the twisted pair with fiber optic cabling. They will be chosen when the transmission distance of two network devices with copper ports need to be extended via fiber optic cabling. When it comes to the fiber-to-fiber conversion, it supports a connectivity not only between multimode fiber and single mode fiber but also a dual fiber link and single fiber using Bi-directional (BIDI) flow. Conversions between different wavelengths can also be achieved by some fiber-to-fiber media converters.

Figure 2: 1*SFP and 2*RJ45 Ports Mini Gigabit Ethernet Media Converter

Connection: Fiber SFP Module vs Fiber Media Converter

A fiber SFP module has a much smaller size than a fiber media converter. Before catching the connection between fiber SFP modules and fiber media converters, we had better know the media converter’s physical structure in advance. So far, copper-to-fiber media converters cover two types of ports. One is for copper (usually the RJ45 port) and the other is for fiber. As for fiber ports, two kinds can also be found. One is designed to insert fiber optic transceivers (SFP, XFP and etc), and the other to connect fiber optic patch cables (SC, LC and etc). As for fiber-to-fiber media converters, both the input ports and output ports are for fiber link. It can be a fiber optic connector for fiber patch cables or an SFF connector for optical modules. After knowing the media converter’s physical structure, it will be easier for us to grasp how does it coordinate with the SFP fiber module. Therefore, if you want to make an SFP module and a media converter both into use at the same time, you need to choose a fiber media converter with fiber ports for an optical transceiver. That is to say, you can insert you SFP module into one side and connect an RJ45 copper cable with the copper port on the other.

Figure 3: 1SFP+1RJ45 Ports Mini Gigabit Ethernet Media Converter

Conclusion

To sum up, in this article, we introduce what the fiber SFP module and the media converter are. Then after studying the media converter’s physical structure and how it coordinates with the fiber SFP module, we can understand the connection between the fiber SFP module and the media converter.

Things You Should Know About SFP+ Transceiver

SFP+ transceiver in short stands for enhanced Small Form-factor Pluggable transceiver. As an enhanced version of SFP, the SFP+ transceiver is also a compact, hot pluggable optic module transceiver. The SFP+ can be used for telecommunications and data communication applications. With various standards, the SFP+ transceiver can be classified differently. In this text, we mainly focus on the SFP+ transceiver’s host interface, data rate, application, and distance.

Types of SFP+ Transceiver

Classified by host interface, the SFP+ fiber optic transceiver can be divided into linear and limiting transceivers. The linear SFP+ module is most appropriate for 10GBase-LRM; otherwise, a limiting module is preferred with the reason that it contains a signal amplifier to re-shape the degraded (received) signal whereas linear does not.

Classified by data rate, the SFP+ transceiver can still be put into three types: 8.5Gb/s SFP+, 10Gb/s SFP+, 16Gb/s SFP+. With its fast development, many vendors can provide a customized one to meet their customers’ different demands.

Classified by application, BiDi SFP+ modules, CWDM SFP+ modules, DWDM SFP+ modules, and other common SFP+ optical transceivers are covered. Considering CWDM and DWDM SFP+ transceivers, they are regarded as the most convenient and cost-effective choices for a campus, data-center, and metropolitan-area access networks using 10 Gigabit Ethernet, with a transmission speed up to 11.25G. The CWDM SFP+ transceiver is designed for bi-directional (BIDI) serial optical data communications such as IEEE 802.3ae 10GBASE-LR/LW/ER. It can support 18 wavelengths from 1270 nm to 1610 nm and has steps of 20 nm, with a transmission distance from 20 km to 80 km. The DWDM SFP+ transceiver is specifically designed for carriers and large enterprises that require a scalable, flexible, cost-effective system for multiplexing, transporting and protecting high-speed data, storage, voice and video applications in point-to-point, add/drop, ring, mesh and star network topologies. It supports more than 40 channels with a transmission distance up to 80 km. As for the BiDi SFP+ transceiver, it’s the enhanced small form-factor pluggable fiber transceiver designed for bi-directional 10G serial optical data communications. Working over one fiber, the BiDi SFP+ uses WDM technology sharing transmission directions into wavelengths of 1270 nm and 1330 nm with a distance up to 10 km, 20 km, 40 km, or 60 km.

Figure 1: 1490nm 80km CWDM SFP+ transceiver connected with single mode LC duplex cable

Classified by wavelength, 10G SFP+ can be grouped into short wavelength SFP+, long wavelength SFP+ and extra long one. For example, SFP-10G-SR belongs to the short wavelength (850 nm), supporting multimode fiber, such as OM3 (300 m) and OM4 (400 m). Besides, the 10G SFP+ copper also belongs to the short one. With an RJ45 connector, it is specifically designed for high-speed communication links that require 10 Gigabit Ethernet over Cat 6a/7 cable with a link limit of 30 m. While SFP-10G-LR can support a long wavelength and a long distance up to 10 km by using a single-mode fiber. For extra long wavelength and extended reach, 10GBASE-ER SFP+ can reach 40 km with the wavelength of 1550 nm by using a single-mode fiber, and also the 10GBASE-ZR SFP+ belongs to the extra long one, which can support the wavelength of 1550 nm with a distance up to 80 km.

Figure 2: 10G copper SFP+ and RJ45 Ethernet cable

Conclusion

With the above introduction, we will have a basic idea of what the SFP+ transceiver is and how many types it has. Since the SFP+ transceiver enjoys lots of strengths, such as high density, low cost, and low power consumption, it has been frequently used in the fiber communications industry. Now that the SFP+ possesses a wide range of types, it can meet their different needs. There is no need to doubt the SFP+ transceiver will keep releasing a huge potential in the future.