Category Archives: Optical Transceiver Solution

How to Select 10G SFP+ Modules for Cisco Switches?

10G fiber optic network is being widespread in today’s telecommunication network. A lot of 10G fiber optic devices like switches are being uses, among which Cisco devices are the most commonly used according to statistics. If you choose a Cisco switch, Cisco original brand or Cisco compatible modules like SFP/SFP+ might be needed for transferring between optical signals and electrical signals. This post will offer details about how to select the proper 10G SFP+ module for Cisco switches.

Understand 10G IEEE Standards and How Cisco Name Its Modules

10G fiber optic network is mature now, and there is a wide selection of 10G IEEE standards for different 10G networking applications and environments. Before you buy 10G SFP+ modules for your Cisco switches, you should firstly get to know these 10G standards.

10G IEEE Standards

IEEE has defined 10G standards for different transmission distance and transmission media. For instance, there are 10GBASE-SR SFP+ for short distance up to 300 meters over OM3 multimode optical fiber and 10GBASE-LR for long distance up to 10 kilometers over single-mode fiber. There are also standards for 10G transmission over copper cables like 10GBASE-CR and 10GBASE-T. The following table listed the details for the most commonly used 10G standards.

10G IEEE Standards	Description
10GBASE-SR	Support 10G transmission over wavelength of 850nm via multimode fiber in short distances: OM3 (up to 300m) and OM4 (up to 400m).
10GBASE-LR	Support 10G transmission over single-mode fiber up to 10km over wavelength of 1310nm.
10GBASE-LRM	Support 10G transmission over standard multimode fiber up to 200m over wavelength of 1310nm.
10GBASE-ER	Operate over 1550nm wavelength and support transmission distance up to 40km over single-mode fiber. Attenuation is required for transmission distance shorter than 20km.
10GBASE-ZR	Support 10G transmission over 1550nm single-mode fiber optic up to 80km. For short links, attenuation is required to ensure transmission quality.
10GBASE-BX	Support duplex 10G transmission over a single single-mode fiber using two different wavelengths up to 80km.
10G CWDM/DWDM	Support 10G transmission over 1550nm single-mode fiber optic up to 80km. For short links, attenuation is required to ensure transmission quality.
10GBASE-CR	Support 10G transmission over Twinax copper cable in very short distance and offer a cost-effective way for connections within racks.

Product Name of Cisco 10G SFP+ Modules

The naming system of Cisco 10G SFP+ modules is closely related to the IEEE standards. Here I listed several examples for Cisco SFP+ module to better illustrate how Cisco names its 10G SFP+ modules.

10G IEEE Standards	Cisco 10G Modules Product Number Example
10GBASE-SR	Cisco SFP-10G-SR
10GBASE-LR	Cisco SFP-10G-LR
10GBASE-LRM	Cisco SFP-10G-LRM
10GBASE-ER	Cisco SFP-10G-ER
10GBASE-ZR	Cisco SFP-10G-ZR
10GBASE-BX	Cisco SFP-10G-BXD-I & SFP-10G-BXU-I; Cisco SFP-10G-BX40D-I & SFP-10G-BX40U-I
10G CWDM/DWDM	Cisco CWDM-SFP10G-1470; Cisco DWDM-SFP10G-61.41
10GBASE-CR	Cisco SFP-H10GB-CU1M; Cisco SFP-H10GB-ACU7M

For common 10G SFP+ modules, Cisco uses the key words of the standards to name the responding modules. For special modules, Cisco has built another naming system.

SFP+ module

For a pair of BiDi SFP+ modules, letter “D” and “U” is used to the two modules that are used together on each end of the fiber optic link. For instance, SFP-10G-BXD-I & SFP-10G-BXU-I is a pair of BiDi Modules that can support transmission distance up to 10km. Additional numbers are added to mark the transmission distance of the BiDi modules. SFP-10G-BX40D-I & SFP-10G-BX40U-I is a pair of BiDi SFP+ modules that can support transmission distance up to 40km.

For CWDM 10G SFP+ and DWDM SFP+, the wavelength is added in the part number. For instance, CWDM-SFP10G-1470 is the part number of a CWDM SFP+ that is operated at wavelength of 1470nm. If you want a CWDM SFP+ operating over 1550nm, then the product number of this CWDM module should be CWDM-SFP10G-1550. As all the DWDM SFP+ modules are operated over wavelengths around 1500nm, in the product number of Cisco DWDM SFP+ modules, the first two number 1 and 5 is eliminated. For example, DWDM-SFP10G-61.41 stands for a DWDM SFP+ transceiver with operating wavelength of 1561.41nm.

10G SFP+ DAC

For modules like SFP+ direct attach cable (SFP+ DAC) and SFP+ active optical cable (SFP+ AOC) which contains a length of cables, Cisco combines the characters of IEEE standard and number to name its modules. Cisco SFP-H10GB-CU1M stands for 10G SFP+ direct attach copper cable that is one-meter long. Cisco SFP-10G-AOC2M is a 2-meter long 10G SFP+ active optical cable.

Do You Really Need Cisco Original Brand SFP+ Module?

Except IEEE standard and transmission distance, to select the proper 10G SFP+ module should also considerate several other factors like compatibility and costs.

Although Cisco has a wide selection of switches and 10G SFP+ modules, but not every SFP+ modules can work well on every Cisco switches SFP+ port. Before selecting the SFP+ msodule for your Cisco switch, you must make sure this SFP+ is compatible with your switch.

The second important factor is the costs for the SFP+ modules. Why? SFP+ module is just a small part of the whole fiber optic network, but the use amount of SFP+ module is very large. Cisco Original brand SFP+ modules are usually expensive. Thus, select cost-effective modules are necessary. Actually, Cisco Original brand SFP+ module is not the only choice. There are also many third party modules that it compatible with Cisco switches. Generally, prices of third party fiber optic transceivers are much lower than the original brand ones.

How to Buy Cisco 10G SFP+ Module?

If you have plenty of money, you can directly order the modules from Cisco. However, if you are going to select the third party modules for a cost-effective solution, then the quality and compatibility would be very important. FS.COM is a provider offers a full range of Cisco compatible modules. All its modules are fully tested in original brand switches to ensure the compatibility and quality. What’s more, FS.COM uses the same naming system as Cisco for its Cisco compatible modules and generic fiber optic modules. A list is also offered in the product page of each fiber optic modules showing the compatible switches and platforms. Customer can use the Cisco product number to search Cisco Compatible and generic modules in FS.COM directly.

Related Article:

Cisco SFP-10G-SR: All You Need to Know

A Comprehensively Understanding of Cisco 10GBASE SFP+ Modules

Increase Network Capacity With BiDi Fiber Optic Modules

BiDi Fiber

Adding more fiber optic cable in the existed fiber optic network is a time and money consuming method to increase the transmission capacity of the network. In most cases, server providers cannot provide that much money and customers do not want to wait that long. To increase the fiber optic network capacity, BiDi fiber optic modules are being suggested for a variety of situations, which can support duplex transmission over a single strand of optical fiber. Now there are a lot of fiber optic transceivers designated with BiDi technologies to increase the network capacity. This post will introduce the most commonly used BiDi modules.

10G BiDi SFP+ 1270-1330

Working Principle of BiDi Fiber Optic Transceivers

Generally, most fiber optic transceivers use two fibers for duplex transmission. However, most BiDi fiber transceivers use two different wavelengths to carry the duplex signals separately. In simple, the two wavelengths are just like two fibers. The optical signals for transmission and receiving are separately converted into signals of specific wavelengths. This is why most BiDi transceivers can support duplex transmission over a single fiber. The following picture shows the basic working principle of a BiDi transceiver.

BiDi transceiver working principle

Commonly Used BiDi Fiber Optic Transceiver

Generally, BiDi transceivers can be divided according to the data rate and package form factors. Currently, the most commonly used BiDi fiber modules can support a data rate ranging from 1G to 40G, and are available in diverse form factor like SFP, SFP+ and QSFP+.

1G BiDi SFP (1000BASE-BX SFP)

For 1G BiDi transceiver, 1G BiDi SFP, also known as 1000BASE-BX SFP modules are often used in today’s network. One thing should be noticed before using BiDi modules, is that the BiDi modules should be used in pairs. As mentioned that BiDi modules use two different wavelengths for transmission. For instance, on one side of you use a BiDi SFP (Tx1310nm/Rx1490nm), on the other side a BiDi fiber SFP using 1490 nm for transmission and 1310 nm for receiving is required. A length of simplex single-mode LC to LC fiber cable is usually used to connect this pair of BiDi SFP module to achieve the connection.

LC/UPC simplex SMF
10G BiDi SFP+ (10GBASE-BX SFP+)

10G BiDi SFP+ modules also have a simplex LC interface, which is also used in pairs and connected by simplex LC fiber cable. Generally, BiDi fiber transceiver can support a long transmission distance. To select the right 10GBASE-BX SFP+ module, wavelength and transmission distance are two important factors to be considered. Currently, 10G BiDi SFP+ modules using 1270nm and 1330 nm for transmission are most commonly used for 10G transmission. 10GBASE-BX SFP+ modules that support transmission distances of 10km, 20km, 40km and 80km are more popular according to statistic from FS.COM. Cisco compatible 10GBASE-BX20-D/U SFP+ and 10GBASE-BX10-D/U SFP+ are the most popular among all the third party 10G BiDi SFP+ modules.

10G BiDi SFP 1330-1270

There are also 10GBASE-BX SFP+ modules in other form factors, like 10G BiDi X2 (10GBASE-BX X2) modules. However, these modules are gradually exiting the market with the upgrading of the devices.

40G BiDi QSFP+ (QSFP-40G-SR-BD)

Unlike other BiDi fiber transceiver like 1000BASE-BX SFP and 10GBASE-BX SFP+, QSFP-40G-SR-BD module has a duplex LC interface. It uses BiDi technologies to achieve four strands of 10G optical signals over a duplex multimode LC fiber patch cable over two different wavelengths. My article (Using 10G Infrastructure for 40G Ethernet With 40G BiDi Optics) has introduced this module in details. The following shows the basic working principle of QSFP-40G-SR-BD. This module can achieve transmission distance up to 150 meters over OM4, 100 meters over OM3 and 30 meters over OM2.

QSFP-40G-SR-BD

BiDi Module Solutions

Using BiDi fiber modules to increase the capacity of the existing fiber optic network is more effective in both time and money than adding more optical cables. Selecting the right BiDi modules should not only consider the data rate, transmission distance, package form factors, and wavelengths, price and quality are also essential factors. If quality and price are your priorities, then FS.COM is the right place to be. Kindly contact sales@fs.com or visit Fiber Optic Transceiver page of FS.COM for more details.

How to Connect 40G QSFP+ SR4 Transceivers to Network

40G network is gradually being applied in today’s backbone transmission network, during which long distance transmission is required. 40G QSFP+ SR4 fiber optic transceiver is being widely applied for 40G transmission in short distances. Generally, 40G QSFP+ SR4, working on wavelength of 850 nm, can support 40G fiber optic transmission a distance up to 150 m over OM4 multimode optical fiber. Inserted in switch, QSFP+ SR4 module utilizes a MTP/MPO interface for dual way transmission. There are a lot of methods to connect QSFP+ SR4 transceivers with other devices for different applications, by using different connectivity products. In addition, the cabling for 40G is relatively more difficult than that of 10G network, which requires more cables and spaces. The following will introduce several high density QSFP+ SR4 transceiver cabling methods.

QSFP+ SR4 40G to 40G Applications

40G to 40G transmission is needed in a 40G fiber optic network. The following picture simply illustrates how 40G to 40G multimode transmission is being achieved by QSFP+ SR4 transceivers. Two QSFP+ SR4 modules are separately inserted in two 40G switches. Then the two transceiver are connected by a length of multimode MTP trunk cable. This is the simplest way to use QSFP+ SR4 transceiver.

In some cases, there are lot of 40G connections required at the same time and same places, which means the increasing of both cable count and cabling difficulty. For better cable management and higher density cabling, a 48-port 1U rack mount MTP fiber patch enclosure can be used as shown in the following picture. Up to four 12-port MTP fiber adapter panels can be deployed in this standard 1U rack mount enclosure. With the help of this 48-port MTP fiber enclosure, cable management for 40G connections could be easier.

QSFP+ SR4 40G to 10G Applications

QSFP+ SR4 is a parallel fiber optic transceiver which means it uses four fibers for transmitting and four fibers for receiving at the same time. The 40G fiber optic signal can be separated into four 10G signals to meet the 40G to 10G transferring requirements. The fiber optic cable count will be increased at the 10G distribution end. Usually a breakout MTP-8LC harness cable is used. For better cable management, a 1U 96-fiber enclosure is recommended, which includes four HD MTP cassettes transferring MTP front the 40G end to LC at the 10G end. Four 10G-SR SFP+ modules, inserted in 10G switch/ports, can be connected to the corresponding LC ports on this fiber enclosure to achieve the duplex transmission between 40G and 10G.

For higher cabling density, the above mentioned 48-port 1U rack mount MTP fiber patch enclosure is still being recommended, which can provide high density 40G MTP cabling environment. And additional MTP-8LC harness cables should be used for transferring signals between 40G and 10G (shown in the following picture).

Conclusion

Depending on its parallel transmission mode, QSFP+ SR4 modules can meet a variety of cabling applications with great flexibility. The above methods is just several commonly used ones, detailed cabling methods for QSFP+ SR4 modules are depended on the practical applications and cabling environments. Related products for the above mentioned methods are listed in the following tables. Kindly visit FS.COM or click the attached links for more details. You can also contact sales@fs.com for more information about 40G cabling.

Products	Description
40G QSFP+ SR4 Module	40GBASE-SR4 QSFP+ 850nm 150m MTP/MPO DOM Transceiver
10G-SR SFP+ Module	10GBASE-SR SFP+, 850nm 300m, MMF, LC duplex
MTP Trunk Cable	12 Fibers OM4, 12 Strands MTP Female to Female, Polarity Type B
MTP-LC Harness Cable	8 Fibers OM4, 12 Strands MTP Harness Cable, Polarity Type B
LC-LC Fiber Patch Cable	1~100M LC-LC Duplex 10G OM4, MMF Fiber Patch Cable
96 Fibers Rackmount Fiber Enclosure	96 Fibers 1U Rackmount Fiber Enclosure loaded with 4 MTP HD Cassettes 2x MTP-12 to Duplex LC/UPC 10G OM4
48 Ports MTP Fiber Enclosure	1U Rackmount FHD Series Fiber Enclosure, Loaded with 4 FAPs (12xMTP)

How to Build 10G CWDM Network

As a passive technology, CWDM allows for any protocol to be transported over fiber optic link at specific wavelengths. CWDM technology is a cost-effective and simple method to increase the capacities of fiber optic network, by using different wavelengths to carry different signals over a single optical fiber. The wide deployment of CWDM network is greatly driven by its affordable cost.

What Is Need for A 10G CWDM Network?

The deployment of a 10G CWDM network is relaying on the exiting fiber optic network. Adding some components on the existing network can largely increase its capacity for data transmission. Here will introduce the key component and an important step during 10G CWDM network deployment.

A Key Component—CWDM Mux/Demux

A key component should be deployed is CWDM Mux/Demux, which combines different wavelength signals from different optical fibers into a single optical fiber, or separates different wavelength signals coming from a single optical fiber to separate optical fibers. The Channel number of a CWDM Mux/Demux is an important factor to divide this device. Standards have identified 18 CWDM Channels. Most of the CWDM Mux/Demux are provided with Channel number range from 2 to 16. However, FS.COM provides a 18-Channel CWDM Mux/Demux which can increase capacity of CWDM network to the most. CWDM Mux/Demuxs also come into a variety of package form factors. The most commonly used are LGX design, rack design and pigtail design.

CWDM Cabling
An Important Step—Connecting CWDM Mux/Demux With 10G Switch

Connecting CWDM Mux/Demux with a 10G switch, is the most important step to build a 10G CWDM network. In simple, to add more devices on the fiber optic network by CWDM technology is to connect the CWDM Mux/Demux with the 10G switches which are linked to the end users. To link CWDM Mux/Demux with the switches, fiber patch cable and 10G CWDM SFP+ transceiver are needed. 10G CWDM SFP+ transceiver should be installed on the switch SFP+ port (some switches use XFP port, then 10G CWDM XFP transceiver is required). Then a length of fiber patch cable should be used to link the transceiver and CWDM Mux/Demux.

CWDM SFP+

How to Select to Right 10G CWDM SFP+ Transceivers?

Choose the Right Working Wavelength: To ensure the right connection, the specific wavelength port should be connected to the same wavelength CWDM SFP+ transceivers. For example, the port on the CWDM Mux/Demux marked with 1270 nm, should be connected to a CWDM SFP+ transceiver that working over wavelength of 1270 nm. As there are 18 different CWDM wavelengths, 10G CWDM SFP+ transceivers that are provided in the market also can 18 different versions for these wavelengths.

Choose the Compatible CWDM SFP+: It is common sense that the fiber optic transceiver should be compatible with the switch which it works on. For instance, if you are using a Cisco switch, the fiber optic transceivers that you used with this switch should be original Cisco transceivers or Cisco compatible transceivers which are provided by third party vendors. The latter is usually the choice of many companies, this is because third party transceivers are usually more cheap than the original brand transceivers. Fiber optic transceivers provided by third party vendor like FS.COM are all fully tested on original brand switch to ensure their compatibility and quality. What’s more, most of FS.COM fiber optic transceivers support same day shipping. Select the right SFP do not only cut your cost and time, but also provide high network performance.

Choose the Transmission Distance According to Your Needs: CWDM network is usually deployed for long distance transmission. Thus the 10G CWDM SFP+ transceiver that are provided in the market usually support transmission distance longer than 20 km, some can support link length up to 80 km or more. You can select the 10G CWDM SFP+ according to your requirements.

Here list the generic whole band 10G CWDM SFP+ fiber optic transceivers that support link length of 20km, 40km and 60km. If you need the brand compatible CWDM SFP+, kindly contact sales@fs.com or visit FS.COM for more details.

Wavelength	20km CWDM SFP+	40km CWDM SFP+	60km CWDM SFP+
1270 nm	44170	44363	44743
1290 nm	44171	44364	44744
1310 nm	44172	44365	44745
1330 nm	44173	44366	44746
1350 nm	44269	44367	44747
1370 nm	44270	44368	44748
1390 nm	44271	44369	44749
1410 nm	44272	44370	44750
1430 nm	44273	44371	44751
1450 nm	44274	44372	44752
1470 nm	44299	44550	44827
1490 nm	44300	44551	44828
1510 nm	44301	44552	44829
1530 nm	44302	44553	44830
1550 nm	44303	44554	44831
1570 nm	44304	44555	44832
1590 nm	44305	44556	44833
1610 nm	44306	44557	44834

Conclusion

With the improvement of technology and market, the cost of CWDM network has decrease a lot. To build a 10G CWDM network is affordable to most companies. For full series of CWDM network Solutions, please visit the following link: WDM Solution

Using 10G Infrastructure for 40G Ethernet With 40G BiDi Optics

During migration from 10G to 40G, one of the most headache problem is that the 10G infrastructure is different from 40G. For example, 40GASE-SR4 QSFP+ transceiver is the most popular solution for 40G transmission in short distances. It uses four 10G lanes to support 40G through a 12-fiber MTP/MPO interface, with four for receiving and four for transmitting and the rest fibers are not in use. However, in traditional 10G transmission, a duplex fiber optic patch cable is enough, with one fiber for receiving and the other for transmitting. This difference requires the change of infrastructure when upgrading 10G network to 40G network. If the 40G QSFP+ transceiver for short distance also using the duplex transmission mode, things would be much easier. That’s why we have 40GBASE-SR BiDi QSFP transceiver. This 40G BiDi optics targeting on 40G Ethernet can finish both the transmitting and receiving via a duplex LC patch cords. LC-LC patch cords

How Does 40GBASE-SR BiDi QSFP Work?

The secret of this 40G BiDi transceiver for short distance is based on the wavelengths. Instead of using four different lanes, this 40G BiDi QSFP uses two duplex 20G transmission mode on two fibers. In simple, each fiber optic should carry two 20G signals over two different wavelengths (usually 850nm and 900nm) respectively. The signal is sent to a target device via 850 nm on one fiber. The signal from the target device is sent via 850 nm on the other fiber. This also works for signals on 900 nm, as shown in the following picture.

40G BiDi QSFP optics

This is why 40GBASE-SR BiDi QSFP transceivers can support 40G Ethernet by using a duplex LC patch cords. Compare with the traditional 40G connection for short distance, 40GBASE-SR BiDi QSFP transceivers is straightforward. Replace the 10G optics by 40G BiDi QSFP optics and no additional cassettes are needed, you can have 40G Ethernet.

40GBASE-SR BiDi QSFP, Just Easier 40G Migration?

The power of 40GBASE-SR BiDi QSFP is definitely not limited to offering easier 40G migration path. 40G BiDi QSFP can also largely decrease the cost for 40G cabling. The traditional 40G short distance links usually pre-terminated 12-fiber MTP/MPO trunk cables with OM3/OM4 fibers, which are expensive than LC multimode patch cords. In additon, for nearly 95% of our data center links are no longer than 200 meters. The 40G BiDi optics can support 40G Ethernet up to 100 meters (OM3) and 150 meter (OM4). That means 40GBASE-SR BiDi QSFP can cover a wide range of using in data center. With LC patch cords being used, more space can be saved. And data center can have better cooling.

40GBASE-SR BiDi QSFP and Cabling Solution

Without changing the 10G cabling infrastructure, you can have 40G Ethernet by using 40GBASE-SR BiDi QSFP transceivers and duplex LC patch cords. The following table offers the 40GBASE-SR BiDi QSFP related products. To meet the high density trend in data center, a new version of LC patch cords with push-pull tab is also provided.

Products	Description
QSFP-BD-40G	40GBASE-SR Bi-Directional QSFP Module 850/900nm,100m(OM3)/150m(OM4) LC Transceiver for MMF
LC/LC OM3 Patch Cords	LC UPC to LC UPC 50/125 OM4 Duplex Multimode Fiber Patch Cable
LC/LC OM4 Patch Cords	LC UPC to LC UPC 50/125 OM4 Duplex Multimode Fiber Patch Cable
Push-Pull Tab LC/LC OM3 Patch Cords	LC-HD to LC-HD Duplex OM3 Multimode Push-Pull Tab Fiber Patch Cable
Push-Pull Tab LC/LC OM4 Patch Cords	LC-HD to LC-HD Duplex OM4 Multimode Push-Pull Tab Fiber Patch Cable

Kindly visit FS.COM for more details.

Tutorials Of Fiber Optic Products

Here You Can Find The Best Fiber Optic Tutorials!