MTP/MPO Fiber Cable and its Application in 40G Network

As the request for greater bandwidth and higher-density fiber optic connections within data centers continues, these requirements must be met by choosing the right type of connectivity. MPO/MTP fiber cable is specially designed for applications for all networking and device needs like 40G modules. It uses a high-density multi-fiber connector system built around precision molded MT ferrule, which are available in UPC and APC polish. It supports both multimode and single-mode applications, and optional lengths available. There are two main MTP/MPO cables types: MPO/MTP trunk cables and MPO/MTP harnesses cables. The following article will have a brief introduction to them individually.

MPO/MTP Standard Trunk Cables

Available in 12, 24, 48 and 72 fibers, MPO/MTP trunk cables work as a permanent link that connects MPO/MTP modules to each other. These cables are used to facilitate rapid deployment of high density backbone cabling in data centers and other high fiber environments reducing network installation or reconfiguration. A 72-fiber MPO/MTP trunk cable (see in the below image) can be terminated with 6 MPO/MTP connectors which are manufactured specifically for multi-fiber loose tube or ribbon cable. The MPO/MTP Trunk cable is designed for Data Center Applications.

These cables can interconnect cassettes, panels or ruggedized MPO fan-outs, allowing for the flexibility in case any decision is made to change the connector style in the patch panels, new cassettes can be installed with the new connector style on the cross-connect side of the patch panel without having to change the connector on the cable trunk.

FS.COM offer single-mode (OS2) and multimode (10G OM3, 10G OM4) MPO/MTP Cable. Single-mode MPO/MTP cable is primarily used for applications involving extensive distances, 10G MPO/MTP cable provide 10G data transfer speeds in high bandwidth applications and they are 5 times faster than standard 50um fiber cable. Work with both VCSEL laser and LED sources, that means, the MTP/MPO trunk cables also provide 40G/100G MPO/MTP trunk cable.

MPO/MTP Harnesses Cables

The MPO/MTP Harnesses cable is MPO/MTP on one end, with single-fiber connectors on another end, single-fiber connector interface available in SC, ST, LC, MTRJ in forms of simplex or duplex channeling. It provides a reliable, cost-effective cabling system for migrating from legacy 10G to higher speed 40G/100GbE. They are suitable for many device needs like 100G modules, including CFP, CFP2 and CFP4 series. MPO/MTP Harnesses cable are available in SM (OS2), MM (OM3/OM4). You could select the suitable fiber according to your own needs with the selection of 12/24/72 fiber cores. The following picture shows the OS2 Fiber Optic Harness Cable.

The MPO/MTP harnesses cable application for data centers requiring quick infrastructure deployment with extended reach that want to maintain bandwidth throughout the infrastructure, its design cater for up-scaling needs and future technologies growth, it’s the best solution, which covers all fiber optic cabling needs in all areas of Data Center.

High-density MTP/MPO Cables for 40G Connection

IEEE 802.3ba 40 Ethernet Standard was ratified in June 2010. This standard specifies MPO connectors for standard-length MMF connectivity. MMF employs parallel optics using MPO interconnects for 40GbE transmission. More specifically, 40G is implemented using eight of the twelve fibers in a MPO connector. Four of these eight fibers are used to transmit while the other four are used to receive. Each Tx/Rx pair is operating at 10G.

Figure 1 shows a Type B MTP female trunk cables for 40GBASE SR4 QSFP+ and multi-fiber migration networks.

Figure 2 shows how to extend your Cisco Nexus 10GBASE-LR networks up to 40G with MTP cable and 4x10GBASE-LR SFP+ transceiver for your high speed data center solution. The 4x 10GBASE-LR SFP+ transceivers interconnection with 1x 40GBASE-LR QSFP+ transceivers (QSFP-40GE-LR4) by one MTP to 4LC harness cable directly.

Fiberstore MPO-based fiber cabling solutions provide a fast, simple and economical way for 40G applications. Certainly, 40G fiber cabling solutions are not only limited to MPO/MTP fiber cables. QSFP cables, especially direct attach copper cables are also recommended. 40G direct attach cable provides a cost-effective solution for high-density network connectivity. You can see the detailed information in an article entitled “40G Direct Attach Cable (DAC) Cables Overview”.

Conclusion

To sum up, MPO/MTP cabling have proven to be an excellent solution for delivering 10G, 40G and 100G transmission, especially within a data center environment. It provides a flexible, high density option for quickly connecting services. FS.COM offers various high-density MPO/MTP fiber optic cables, trunk and harness versions, patch cords, and cassette module. The MPO/MTP fiber cables are tested with guaranteed quality, and they can be installed easily, which saves time and money. Besides MPO/MTP cables, other cables are also supplied, like LC to ST fiber cable, LC SC cable, SC SC fiber cable, and so on.

Guide to Two 40GBASE-LR4 QSFP+ Links - CWDM and PSM

The common 40GBASE-LR4 QSFP+ optical transceivers that are available on the market are QSFP-40GE-LR4, QSFP-40G-LR4, QSFP-40G-LR4-S and WSP-Q40GLR4L. They are all compatible with 40GBASE-LR4 standard, but differ with each other. Since I have already explained the difference between the above 4 optical transceivers, I will not go further about these topic today. Except for the different 40GBASE-LR4 QSFP+ transceivers types, there are also two links for 40GBASE-LR4 standards. One is coarse wavelength division multiplexing (CWDM). The other is parallel single-mode fiber (PSM). In this article, these two links of 40GBASE-LR4 QSFP+ transceivers will be introduced to you.

40GBASE-LR4 CWDM QSFP+ Transceiver

The 40GBASE-LR4 CWDM QSFP+ transceiver (like QSFP-40GE-LR4) is compliant to IEEE P802.3ba 40GBASE-LR4 standard. This QSFP module supports link lengths of up to 10km over single-mode fiber (SMF) with duplex LC connectors. This transceiver converts 4 inputs channels of 10G electrical data to 4 CWDM optical signals by a driven 4-wavelength distributed feedback (DFB) laser array, and then multiplexes them into a single channel for 40G optical transmission, propagating out of the transmitter module from the SMF. Reversely, the receiver module accepts the 40G CWDM optical signals input, and demultiplexes it into 4 individual 10G channels with different wavelengths. The central wavelengths of the 4 CWDM channels are 1271, 1291, 1311 and 1331 nm (defined as members of the CWDM wavelength grid in ITU-T G694.2). Each wavelength channel is collected by a discrete photo diode and output as electric data after being amplified by a transimpedance amplifier (TIA).

40GBASE-LR4 PSM QSFP+ Transceiver

Unlike CWDM QSFP+ transceiver using a LC connector, PSM QSFP+ is a parallel single-mode optical transceiver with an MTP/MPO fiber ribbon connector. It also offers 4 independent transmit and receive channels, each capable of 10G operation for an aggregate data rate of 40G on 10km of single-mode fiber. Proper alignment is ensured by the guide pins inside the receptacle. The cable usually cannot be twisted for proper channel to channel alignment. In terms of a PSM QSFP+, the transmitter module accepts electrical input signals compatible with common mode logic (CML) levels. All input data signals are differential and internally terminated. The receiver module converts parallel optical input signals via a photo detector array into parallel electrical output signals. The receiver module outputs electrical signals are also voltage compatible with CML levels. All data signals are differential and support a data rates up to 10.3G per channel.

Compare 40GBASE-LR4 CWDM QSFP+ With 40GBASE-LR4 PSM QSFP+ Transceiver

As noted before, 40GBASE-LR4 CWDM QSFP+ transceivers use a duplex LC connector via 2 optical single-mode fibers to achieve 40G without making any changes to the previous 10G fiber cable plant. However, 40GBASE-LR4 PSM QSFP+ transceivers use an MTP/MPO fiber ribbon connector via 8 optical single-mode fibers to reach 40G. Obviously, CWDM QSFP+ is a more cost-effective solution for 40G connectivity.

What’s more, in terms of the inner structure of an optical transceiver module, PSM QSFP+ uses a single uncooled CW laser that splits its output power into four integrated silicon modulators, which is much inexpensive than CWDM QSFP+. Besides, its array-fiber coupling to an MTP connector is relatively simple. A picture comparing the key differences between CWDM and PSM is shown below:

Additionally, the caveat is that the entire optical fiber infrastructure within a data center, including patch panels, has to be changed to accommodate MTP connectors and ribbon cables, which are more expensive than conventional LC connectors and regular SMF cables. Not to mention that cleaning MTP connectors is not a straightforward task.

Conclusion

PSM and CWDM are the two links of 40GBASE-LR4 QSFP+ transceivers. Both of them can support a link distance of 10km. However, 40GBASE-LR4 CWDM QSFP+ are more common than 40GBASE-LR4 PSM QSFP+ because of its performance and low cost. Fiberstore offers a wide brand compatible 40G CWDM QSFP+ transceivers. Each of our fiber optic transceivers has been tested to ensure its compatibility and interoperability. For more information or quotation, please contact us directly.

Upcoming 40/100G Technology

The past decades witnessed the tremendous advancement in Ethernet network transmission speeds from 10/100 base systems to 1G then 10G deployments. Today, 10G server uplinks are ubiquitous in the data center, driven by the need for higher bandwidth, 40/100G server uplinks are just around the corner. IEEE ratified 40/100G Ethernet Standard in June 2010. Since then people were hoping to embracing this new Gigabit Ethernet. However, migrating to higher data rates seems not be that easy. This article will pay special attention to those aspects that influence the migration path.

New Transceiver Interface: MPO Connector
When transition to 40/100G, parallel optics are needed to transmit and receive signals. Because for 40G, there are 4-Tx and 4-Rx fibers, each transmitting at 10G for an aggregate signal of 40G. And for 100G, there are 10-Tx and 10-Rx. As parallel optics technology requires data transmission across multiple fibers simultaneously, a multifiber (or array) connector is required. Defined by TIA-604- 5-C, Fiber Optic Connector Intermateability Standard, MPO (FOCIS-5) is an array connector that can support up to 72 optical fiber connections in a single connection and ferrule. Factory-terminated MPO solutions allow connectivity to be achieved through a simple plug and play system. And this MPO-terminated backbone/horizontal cabling is simply installed into preterminated modules, panels, or Harnesses.

40G Ethernet Solution
According to IEEE 802.3ba, 40G was designated to support high-performance computing clusters, blade servers, SANs and network-attached storage. When deploying 40G network, QSFP transceiver and a 12-fiber MPO will be utilized. Deployment of 40G over multimode fiber will be achieved with 4-Tx and 4-Rx fibers from the 12-fiber MPO. The fibers will be the outer fibers as shown in Figure 3. Each of these four “channels” will transmit 10G for the combined 40G transmission. While single-mode fiber transmission will remain duplex connectivity using course wavelength division multiplexing. Some transmission media for 40G are to be included in the following table.

• 40 GBASE-SR4 (parallel optics)

—100m on OM3/125m on OM4, 10G on four fibers per direction

• 40 GBASE-LR4 course wavelength division multiplexing (cWDM)

—10km on single-mode fiber, 4x 10G 1300 nm wavelength region like QSFP-40GE-LR4

• 40 GBASE-CR4

—7 m over copper, 4 x 10G (twinax copper)

100G Ethernet Solution
40G is to support increasing bandwidth demand for server computing, while 100G was designated to support switching, routing and aggregation in the core network. For 100G deployments, the CXP will be the electronics interface for OM3/OM4 multimode fiber, while CFP will be the interface for single-mode fiber. For 100G transmission over multimode fiber, the optical connector interface will be the 24-fiber MPO connector that will support 10-Tx and 10-Rx channels, each transmitting at 10G. Transmission over single-mode will be achieved via wavelength division multiplexing with duplex connectivity.

• 100 GBASE-SR10 (parallel optics)

—100m on OM3 or 125m on OM4, 10G on 10 fibers per direction

• 100 GBASE-LR4 (dWDM)

—10km on single-mode, 4 x 25G 1300 nm

• 100 GBASE-ER4 (dWDM)

—40km on single-mode, 4 x 25G 1300 nm

• 100 GBASE-CR10

—7 m over copper, 10 x 10G (twinax copper)

Cabling Migration From 10G to 40G to 100G in an MPO-based System
Starting with 10G, a 12-fiber MPO cable is deployed between the two 10G switches. Modules are used at the end to transition from the 12-fiber MPO to LC duplex. This enables connectivity into the switch (Figure 3).

For 12-fiber MPO cassette-based optical systems already installed, 40G migration is as simple as replacing the existing cassette from the patch panel housings at the equipment and cross connects with an MPO adapter panel. The use of a 12-fiber MPO jumper is needed to establish connectivity between the switches (Figure 4).

Future 100G networks will require a 24-fiber MPO jumper to establish a link. Systems that use 12-fiber MPO backbone cabling will need a 24-fiber to two 12-fiber MPO jumpers (Figure 5).

Future Proofing
As we transition to 40G and 100G, an MPO-based trunk with appropriate fiber can be installed, which will provide an easy migration path to future higher-speed technology. This article has mentioned some optical devices and cabling solutions to support 40/100G Ethernet. Fiberstore provides a large amount of 40/100G equipment like 40G QSFP+ (JG661A), 40G DAC and AOC, etc. CFP, CFP2, CFP4 and QSFP28 are also offered with very competitive prices and high quality. To best meet the needs of the future, future proofing is crucial. So if you have any requirement of our products, please send your inquiry to us.