FS.COM 40G QSFP BiDi Transceiver 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 40GBASE-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 40GBASE-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.

Figure1. 40GBASE-SR4 transceiver: 12-fiber strands, only 8-fiber strands used

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

40G QSFP BiDi Transceiver Solution

40GBASE-SR Bi-Directional QSFP 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.

Figure2. 40GBASE BiDi transceiver: duplex LC

Cost Comparison

It may be not so intuitive that 40G QSFP BiDi transceiver 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.

Figure3. Direct 40G connections

From the figure, it shows that the 40G SR4 transceiver uses MPO connector and 40G QSFP BiDi transceiver uses LC connectors. Therefore, with 40G SR4 transceiver, 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 40G SR4 transceiver, QSFP BiDi transceiver can save the cost by 100%.

Fiber Cable Lengths (meters)		10	30	50
288 connections for QSFP BiDi Transceiver	FS.COM LC MMF cables	2304	5760	9216
288 connections for 40G SR4 Transceiver	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 40G SR4 transceiver connections would be much higher.

Conclusion

QSFP BiDi transceiver 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 40G SR4 transceiver solution is already cheap. Since we devotes to serving our customers with the most cost-effective network connection solutions, we would like to introduce QSFP BiDi transceiver.

Originally published at www.fiber-optic-equipment.com

40 Gigabit Ethernet Solution

40 Gigabit Ethernet is a standard that enables the transfer of Ethernet frames at speeds of up to 40 gigabits per second (Gbps), allowing 40 Gigabit Ethernet-enabled equipment to handle traffic at the aggregation and core layers. It satisfies the greater demands for faster data transmission and higher bandwidths. Thus, the business case for 40 Gigabit Ethernet is becoming inescapably compelling although 10 Gigabit Ethernet is still making its way into data center. A right and cost-effective solution for 40 Gigabit Ethernet is very necessary for all users who want to migrate to 40 Gigabit Ethernet.

The picture above is the summary about 40 Gigabit Ethernet, explaining significantly that cables and transceivers are the basis of the whole solution. And actually, they are also the main cost of the item. Next some types of 40 Gigabit Ethernet cables and 40 Gigabit Ethernet transceivers will be introduced in details.

40 Gigabit Ethernet Cables

The cable applied in 40 Gigabit Ethernet can be optical fiber or copper cable. The copper cable for 40 Gigabit Ethernet is designed for short reach, up to at least 7 m. As to optical cable, there are two types: singlemode cable and multimode cable. The transmission distance of multimode cable for 40 Gigabit Ethernet can be up to 150 m, which is much shorter than the transmission distance of singlemode cable (It can be up to 10 km). Generally, the common used types are OM3 and OM4 multimode cables in that its reach supports a wider range of deployment configurations compared to copper solutions, and the cost is lower compared to singlemode solutions.

What is more, the MPO (Multi-Fiber Push On)/MTP (Multi-fiber Termination Push-on) cable is considered the best solution for 40GbE. It can connect the multimode transceivers to support the multifiber parallel optics channels. For 40 Gigabit Ethernet, we can use 8 fibers MPO/MTP harness cables or 12 fibers MPO/MTP trunk cables. The former is to directly connect a QSFP port to other 4 SFP+ ports. The latter is to directly connect one QSFP port to another QSFP port. Here is a picture to help you know it clearly.

40 Gigabit Ethernet Transceivers

According to different standard form factors, 40 Gigabit Ethernet transceivers can be divided into different types, such as CFP transceiver, CXP transceiver and QSFP transceiver, ect.

CFP transceiver, which has 12 transmit and 12 receive 10-Gbps lanes, can support one 100 Gigabit Ethernet port, or up to three 40 Gigabit Ethernet ports. This module is used for 40GBASE-SR4, 40GBASE-LR4. The former is based on 850nm technology and supports transmission over at least 100m OM3 parallel fibers and at least 150m OM4 parallel fibers, while the latter is based on 1310nm , coarse wave division multiplexing (CWDM) technology and supports transmission over at least 10km on singlemode fiber.

CXP transceiver also has 12 transmit and 12 receive 10-Gbps lanes as well as CFP transceiver, supporting one 100 Gigabit Ethernet port or up to three 40 Gigabit Ethernet ports. Compared with CFP transceiver, the size of it is much smaller. And it is mainly designed for the high-density requirements of the data center, serving the needs of multimode optics and copper.

QSFP transceiver provides four transmit and four receive lanes to support 40 Gigabit Ethernet applications for multimode fiber and copper today. The size of it is the same with CXP transceiver. It is mainly designed to support Serial Attached SCSI, 40G Ethernet, PCIe, 20G/40G Infiniband, and other communications standards.

Fiberstore 40 Gigabit Ethernet Solution

Fiberstore can offer customers 40 Gigabit Ethernet connectivity options for data center networking, enterprise core aggregation, and service provider transport applications. Since the products are all in good quality and low price, it may be the best choice for you to deploy the network.

Originally published at http://www.chinacablesbuy.com/