Tag Archives: 40G QSFP+

How to Extend 40G Connection up to 80 km?

As 40G connectivity is accelerating, many data centers prepare to migrate from 10G to 40G. But the link distance between 10G and 40G switches is a big challenge. This article can help you extend 40G connection distance.

Current 40G QSFP+ to 4x10G Connection—Max 10 km

As we know, 40GBASE-SR4 QSFP+ is designed for short distance of up to 150m connection. 40GBASE-PLR4 QSFP+ can support long distance link of up to 10 km. Both 40G QSFP+ modules are interfaced with 12-fiber MTP/MPO and can break out into 4x10G connection. To build 10G-40G connection, for instance, using singlemode 8-fiber MTP-LC harness cable to connect 40GBASE-PLR4 QSFP+ and 4x10G SFP+ modules. As the direct connection distance between two 40GBASE-PLR4 QSFP+ optics can reach at most 10km, it’s easy to understand that the connection between 10G and 40G may be shorter. However, we provide a method to extend 40G connection to 80km distance. Continue to read this article and find the answer.

10km max

Equipment for Extending 40G QSFP+ Connection

To extend 40G QSFP+ connection distance, we have to use WDM transponder OEO (Optical-Electrical-Optical) repeater. OEO repeater allows connection between fiber to fiber Ethernet equipment, serving as fiber mode converter, or as fiber repeater for long distance transmission. It can also function as CWDM/DWDM optical wavelength conversion. Now we will use a multi-service transport system, including a hot-swappable plug-in OEO card which only occupies 1 slot. The other space can be left for holding more cards such as DCM, EDFA, OLP. On the left side, there is a card for centralized network management.

WDM transponder oeo

This is a 4-channel multi-rate WDM transponder with an OEO-10G card containing 8 SFP/SFP+ slots and can support up to 11.3G rate. The OEO card can convert 1G~11.3 Gbps Ethernet signals into a corresponding wavelength in CWDM and DWDM network infrastructures. Transmission distance can reach 80 km.

Except WDM transponder OEO repeater, we still need DWDM Mux/Demux and DWDM SFP+ to extend the distance to 80 km. DWDM Mux/Demux is to combine 4x10G signals of different wavelengths on one single fiber so that it’s the best solution to increase network capacity and save cost. Here we use 40-channel C21-C60 dual fiber DWDM Mux/Demux. So we can choose suitable 10G DWDM SFP+ modules 80km transceiver between the wavelengths of C21 and C60.

For your reference, the equipment for 40G connection extension mentioned above are from FS.COM. You can select those of other specifications according to your own needs.

Equipment Details
Fiber Transceiver 40GBASE-PLR4 QSFP+ 1310nm 10km MTP/MPO Transceiver
Generic Compatible 10GBASE-LR SFP+ 1310nm 10km DOM Transceiver
C21-C60 DWDM SFP+ 80km DOM Transceiver
Transponder Repeater 4-channel WDM transponder OEO repeater
DWDM Mux/Demux 40 Channels C21-C60 Dual Fiber DWDM Mux Demux with Monitor Port, 3.0dB Typical IL
Extend 40G QSFP+ Connection to 80 km

Install 40GBASE-PLR4 QSFP+ into QSFP+ port of a switch and 4 10GBASE-LR SFP+ into the Ethernet ports of the WDM transponder OEO repeater. Then plug a singlemode 8-fiber MTP-LC harness cable to connect 40GBASE-PLR4 QSFP+ and 4 SFP+ modules. Because of the OEO repeater function, 4x10G Ethernet signals are converted into corresponding wavelengths in DWDM network infrastructure. Then install 4 x 10G DWDM SFP+ transceivers into other four ports of OEO repeater. Next step is to connect DWDM SFP+ modules on the OEO repeater and DWDM Mux/Demux by using LC duplex patch cables. In this way, 40G QSFP+ distance can be extend up to 80 km.

40G-80km

Conclusion

10 km transmission distance is not the limit of 40G to 4x10G connection. From this article, you can extend 40Q QSFP+ to 80 km by mainly applying WDM transponder OEO repeater, DWDM Mux/Demux and 10G DWDM SFP+. If need to break your network distance limit, please visit our site www.fs.com or contact us via sales@fs.com.

Related articles:

Economically Increase Network Capacity With CWDM Mux/DeMux
Check out All CWDM Transceiver Modules
User Guide for CWDM MUX/DEMUX

How to Select Fiber Patch Cable for 40G QSFP+ Modules?

As the speed changes from 1 to 10 Gbps and now increases from 10 to 40 Gbps and even 100 Gbps, data centers develop into more complex systems. So different optical technologies and cabling infrastructure are required. For 40G data rates, the special transceiver module is QSFP+ (Quad Small Form-Factor Pluggable Plus). To build 40G data centers, you need to select suitable fiber patch cable for 40G QSFP+ Modules. But how?

40G transmission network needs advanced switch, matched patch cords and transceiver modules. The quality of these connections can largely affect the reliability and stability of the whole 40G network. However, connectivity of 40G is much more complex than ever. Thus, selecting the proper fiber patch cables for 40G network is more difficult and becomes a big issue in 40G migration. As mentioned, QSFP+ transceivers are suggested for 40G, this article will provide as detailed as possible about fiber patch cable selection for 40G QSFP+ transceivers.

40G QSFP+ transceivers

Patch cable is very important to 40G network not only because the switch connections necessity, but also because of the transmission principle of the fiber optic signals and the high density trend of 40G transmission. Several important factors like cable, connector and switch port should be taken into account when selecting patch cords for 40G QSFP+ transceivers.

Single-mode or Multimode Fiber Patch Cable

Fiber Patch Cable able is essential for the network performance. Optical signals perform differently when information transforms through the cables with different wavelengths. When people buy fiber optical patch cords for 40G QSFP+ transceiver, they often ask if a 40GBASE universal QSFP+ transceiver working on wavelength of 850nm can be used with OM1 patch cords. The answer is yes, but not suggested. Why? As the optical signal transmission distance gets shorter, the data rate increases. The transmission distance and quality would be limited by using OM1 optical cable with 40G QSFP+ transceiver. OM1 cable is only suggested for 100 Mb/s and 1000Mb/s transmission. Two upgraded cables—OM3 and OM4 are suggested for 40G QSFP+ transceivers in short distance.

IEEE has announced standards for 40G transmission in both long distance and short distance, which are 40GBASE-LR4 and 40GBASE-SR4. (LR stands for long reach and SR stands for short-reach and). For long reach, single-mode fiber is suggested for 40G transmission with the distance up to 10 km. For short reach, multimode fiber—OM3 (up to 100 meters) and OM4 (up to 150 meters) is suggested for 40G transmission. OM3 and OM4, which are usually aqua-colored, are accepted economic solutions for 40G in short distance with lower insertion loss and higher bandwidth.

MTP or LC Fiber Patch Cable 

The connector type of the patch cords should depend on the interface of 40G QSFP+ transceiver. Now there are two interfaces commonly adopted by 40G QSFP+ transceiver and they are MTP and LC. Usually 40G QSFP+ transceiver with MPO interface is designed for short transmission distance and LC for long transmission distance. However, several 40G QSFP+ transceivers like 40GBASE-PLR4 and 40GBASE-PLRL4 have MPO interfaces to support long transmission distance.

mtp and lc connectors for qsfp+

High density is the most obvious characteristic of 40G transmission, which is largely reflected in the MTP connectors on patch cords used with 40G QSFP+ transceiver. As QSFP+ transceiver uses four 10G channels, MTP cable which uses 4 pairs of fibers with can provide a time-save and stable solution for 40G QSFP+ transceivers.

Besides, 40G QSFP+ transceiver with LC interface is also available. This type of QSFP transceiver uses four lanes with each carrying 10G in 1310nm window multiplexed to achieve 40G transmission. For this type, patch cable with duplex LC connector should be used.

Switch Port

The importance of network flexibility gradually reveals as the speed of Ethernet increases. Cabling options for 40G network are 40G QSFP+ to 40G QSFP+, 40G QSFP+ to SFP+. It’s very common that 40G ports is needed to be connected with 10G port. In this case, fan out patch cable with MTP connector on one end and four LC duplex connectors on the other end is suggested (as shown in picture below).

Factors like single-mode or multimode fiber jumpers, fiber patch cable connector and switch port are important in selecting the right patch cords for 40G QSFP+ transceivers. They are closely related to the transmission distance, network flexibility and reliability of the whole 40G network. But in practical cabling for 40G QSFP+ transceivers, there are more need to be considered. Planning and designing takes a lot of time and may not achieve results good enough. However, Fiberstore can solve your problems with professional one-stop service including the cost-effective and reliable network designing and 40G products.

Originally published at http://www.articlesfactory.com/articles/communication/how-to-select-fiber-patch-cable-for-40g-qsfp-modules.html

MTP Trunks for High Density Data Center

The need for high bandwidth has never stopped. High bandwidth means more fibers are needed for the cabling infrastructure. The demands certainly change the network architecture to be more complicated. For spine-and-leaf architecture, each leaf switch in the network is interconnected with every spine switch. As a result, with leaf-spine configuration in data centers, fiber counts can multiply very quickly compared with traditional three-layer distribution architectures.

Besides, 40GbE and 100GbE grow quickly in the data center. Relatively, the interface of parallel optics like 40G QSFP+ changes to be MPO/MTP with 12-fiber instead of duplex fiber. And that also increases the fiber counts in your data center structured cabling. As data center evolves, links require 144 fibers, 288 fibers or even more. So data center managers are in front of many challenges such as limited space, deployment efficiency and of course the cost.

MTP Trunks Deployment Solutions

To address these challenges, many data center cabling designs use MTP trunks with up to 144 fibers. In data centers requiring more than 144 fibers, multiple runs of a 144-fiber cable assembly are typically installed to achieve the total desired fiber count. For example, if a link requires 288 fibers from the main distribution area of the data center to another location, two 144-fiber trunk cables would be installed. This method can reduce the physical space capacity for future growth. Figure 1 depicts the space savings across three deployment scenarios in a 12-inch x 6-inch cable tray with a 50 percent fill ratio:

  • 4,440 total fibers using 370 x 12-fiber MTP trunks
  • 13,680 total fibers using 95 x 144-fiber MTP trunks
  • 16,128 total fibers using 56 x 288-fiber MTP trunks

comparison

Figure 1. Comparison of trunks with different fibers

MTP connectivity is one of the important solutions used in high density environment. MTP cable allows for the deployment of optical fiber termination of 12 fibers at a time rather than individual termination of single fiber strands. In addition, this kind of cabling is easy for future migration to 40/100/200/400GbE networks using parallel optical technologies. To achieve high-fiber-count cable and connectivity, various implementation options are available.

MTP Trunks

MTP trunk cable assemblies are offered in fiber types in standard 12, 24, 48, 72, 96 or 144 core versions in a compact and rugged micro-cable structure. With high port density, it brings big savings in installation time and cost. Due to its discreet premium connectors and special fiber, it delivers low insertion loss and power penalties in high speed network environment. And the multifiber connector and compact dimension also ease the space pressure in costly data centers.

MTP trunk cables are available in either mesh bundles or distribution fan-out trunks since infrastructure designs, cabling environments and pathway types are different, MTP connectivity in backbone cabling can employ different methods. Below are two possibilities:

Cables that are factory terminated on both ends using MTP connectors (MTP-MTP trunks)
Cables that are factory terminated on one end using MTP connectors (MTP pigtail trunk)

MTP-trunks

Figure 2. MTP assemblies types

MTP-MTP Trunks

MTP trunk assemblies are used where all fibers are landed at a single location at each end of the link—for example, between the main distribution areas (MDAs) and the server rows or between the MDA and the core switching racks in a computer room or data hall, as Figure 3 shows. Additionally, MTP-MTP trunks also appear between MDAs of multiple computer rooms or data halls where open tray is the pathway.

same-computer-room

Figure 3. MTP-MTP trunk assembly deployed in a computer room

MTP Pigtail Trunks

MTP pigtail trunks can be used for environments where the pathway doesn’t allow for a pre-terminated end with pulling grip to fit through—for example, a small conduit space (see Figure 4). This approach is common when needing to provide connectivity between MDAs of multiple computer rooms or data halls. Additionally, a deployment using pigtail trunks can be useful when the exact pathway or route is not fully known, avoiding exact length measurement before ordering of the assembly.

two-computer-rooms

Figure 4. MTP pigtail trunk field terminated in two computer rooms

Conclusion

Many factors should be considered to plan and install a data center cabling infrastructure for actual and future needs, especially in high density environments. So before choose the best cabling installation solution, you need to take following points into concern:

  • Application environment: inside or between computer rooms or data halls
  • Design requirements: traditional three-layer or spine-and-leaf architecture
  • Future proofing: transition path and future-technology support

From this article, high-fiber-count MTP trunks are the best solution for your backbone cabling. MTP trunks is useful for faster installation, lower pathway congestion and greater efficiency while delivering the bandwidth to meet the needs of 40GbE/100GbE/200GbE and beyond.

Cost-effective QSFP-40G-SR-BD Solution

25 Gigabit Ethernet emerges as the shinning star. It provides another solution (10G-25G-100G) migrating to 100 Gigabit Ethernet. But for those who just want to use 40G network instead of 25G at present, then they need to upgrade from 10G to 40G connections. As to the migration from 10G to 40G, this article will introduce a cost-effective solution – 40G quad small form-factor plugable (QSFP) bidirectional (BiDi) transceiver solution.

Traditional 40G Transceivers Solution

Fiber cabling infrastructure of 10G and 40G transceivers are different. 10GBASE-SR transceivers require multimode fiber (MMF) cable with LC connectors. While QSFP-40G-SR4 or CSR4 transceivers connect with MMF ribbon cable with MPO/MTP connectors. It means that 40G connectivity can’t reuse the 10G network cabling infrastructure. That causes great cost.

Except the connector type, there is another concern. 10GBASE-SR transceivers require 2 fiber strands per 10G link, while QSFP-40G-SR4 and CSR4 transceivers need 8-fiber strands (actually it’s 12 fiber strands.). That is because 40GBASE-SR4 and CSR4 transceivers use 4 parallel fiber pairs (8 fiber strands) and each pair at 10G for total 40G full duplex. In this case, 4 fiber strands are not used and wasted.

traditional-qsfp

Figure1. QSFP-40G-SR4: 12-fiber strands, only 8-fiber strands used

As a result, the connector’s change and the increased fiber density required for QSFP-40G-SR4 need a significant cable plant upgrade. That makes it expensive for pmmfeople to migrate form 10G to 40G network in their existing data centers.

40G bidi

QSFP-40G-SR-BD is a short-reach transceiver that delivers 40 Gbps over a duplex OM3 or OM4 MMF connection. This connection can reach the distance up to 100 meters over OM3 MMF and 150 meters over OM4 MMF. This 40G transceiver has two 20G channels. Each channel transmits and receives two wavelengths over a single MMF strand. So the transceiver supports connections over a LC duplex MMF cable.

bidi-qsfp

Figure2. QSFP-40G-SR-BD: duplex LC

Cost Comparison

It may be not so intuitive that QSFP-40G-SR-BD solution can save more cost than the traditional 40G transceivers. Let’s take a look at the following case of upgrading 10G to 40G network and compare the cost of two kinds of solutions.

In an unstructured cabling system, devices are connected directly with fiber cables. This direct-attachment design is suitable for short distance connection in a data center.

288 connections

Figure3. Direct 40G connections

From the figure, it shows that the QSFP-40G-SR4 uses MPO connector and QSFP-40G-SR-BD uses LC connectors. Therefore, with QSFP-40G-SR4, to realize the migration, all of the existing 10G MMF cabling infrastructure should be replaced because the connector are different. But it’s another case to QSFP BiDi transceiver. The existing 10G MMF cables can be reused to achieve the network upgrade from 10G to 40G. This doesn’t require any cost on cables.

In the table, the cable costs and savings of migration and new deployment of 288 direct connections. To migrate the existing 288 10G to 40 connections, FS.COM QSFP BiDi transceiver doesn’t need any cost on cable. Compare to QSFP-40G-SR4 , QSFP-40G-SR-BD can save the cost by 100%.

Fiber Cable Lengths (meters) 10 30 50
288 connections for QSFP-40G-SR-BD FS.COM LC MMF cables 2304 5760 9216
288 connections for QSFP-40G-SR4 FS.COM MPO cables 21024 37440 51840
Cost Savings from 10G to 40G (US $) 21024 37440 51840
Cost Savings of New 40G deployment (US $) 18720 31680 42624

For the case in which 288 new direct 40G connections are needed in addition to the existing cabling infrastructure for a data center migration, the savings can reach as much as 82% with the use of QSFP BiDi transceiver. This above costs doesn’t include that of installation. It’s not hard to imagine the installation cost of QSFP-40G-SR4 connections would be much higher.

Conclusion

QSFP-40G-SR-BD is a new breakthrough in 40G network. It helps the users to realize the migration from 10G to 40G without the need of replacing all 10G cabling infrastructure. Actually, compared with solutions of some other companies, FS.COM QSFP-40G-SR4 is already cheap. Since we devotes to serving our customers with the most cost-effective network connection solutions, we would like to introduce QSFP-40G-SR-BD.