Know all about migrating to 40 and 100G with OM3 and OM4 connectivity


Continued requirement for high speed networks require cabling solution to be quite scalable and friendly to expansions. These not only should be manageable easily, but also should have certain degree of future readiness so that – cost of expansion and ease of deployment – both factors can be taken care of easily. In consonance with the need to be able to achieve higher data rates with existing cabling infrastructure, a number of standards have been finalized , such as, 40- and 100-GbE, 32-Gb and higher speed Fibre Channel, and 40-Gb and high InfiniBand. All these cabling standards have put OM3 and OM4 optical fiber connections to better use.

Things you need to move to 40G and 100G connectivity

Industry standard for complete guidance: The Institute of Electrical and Electronics Engineers 802.3ba was ratified some time back to provide guidelines for 40G/100G Ethernet standard. This standard provides complete know-how on how to achieve 40/100G fiber connection using multimode and singlemode fibers. Thus, this standard has kept OM3 and OM4 fiber types of multi-mode nature in the focus to enable existing cabling models to support high speed data transmission.

Technology: Makers seek solace in parallel optics technology to introduce 40G and 100G data transmission in the data centers. This technology requires fiber optic connectors and cables to deliver the best results.

 Optic fibre 40G MPO system – 12 fiber MPO connector us used. 10G is sent along each fibre strand in Tx-Rx direction. Thus, 8 of the 12 fibers receive the light wave and deliver 40G parallel transmission.


What happens in parallel optics technology?

In parallel optics technology, multiple paths are used for sending signals at higher data rate. So, in addition to this technology, you need a ribbon optical connection cable of 12 and 24 fiber configuration, with all fibers aligned in a linear array. The devices on either side of this arrangement are provided with multiple receiver and transmitter ports. The receiver ends communicate with the transmitter ends allowing the transfer of 4 2.5G signals to merge into single 10G signal starting from A and reaching B.

Suitable connectors: MPO/MTP connector that has 12 or 24 fiber configuration supports this technology perfectly and that is why; used largely for making the existing cabling framework relevant to higher speed networks.

Cabling solutions: Migration to 40G and 100G networks require these two types of cables. The first is MTP trunk cable that has an MPO connector on either terminations of a ribbon cable with 12 or 24 fibers. The MTP connection varies to the point where 24 fibers converge into the MPO connector.

Another type of cable useful is a fan-out cable. This cable finds utility in connecting LC or SC connector interfaces with MTP connector.

How to complete the migration process

The main methods of establishing 40G or 100G connection in data centers are

  1. Connecting duplex LC patchcords directly to equipment outlet – It involves establishing MTP connection comprising of MPO/MTP connector – LC Duplex Fanout cable with optional LDP. It can be called Fibre patch panel-patch chord connection too. In actual, Duplex LC patchcords connect directly to the Equipment Outlet.
  2. MTP – LC breakout optical connection cable linked to Equipment Outlet – Though this option is less flexible and demands exact cord length, it is certainly useful to connect fiber with MPO adapter.
  3. Connecting MTP Trunk cable to MTP cassette that is visible as connection between LC Duplex Patchcords from Cassette to Equipment Outlet.

Once these configurations are achieved you need to know how to connect fiber optic cable with the equipment. Here is how to connect fiber optic cables to the intended equipment.

  1. Select a fiber optical cable suitable to the target equipment and also ascertain the location where this is to be installed – whether aerial, on ground or underground. You also need to ascertain the expansion need and add single mode fiber with the multimode ones accordingly.
  2. Splice the fiber cables to the required length or according to the prescribed standards and pick the correct splice closure.
  3. Choose fiber optic connectors compatible with the communications equipment
  4. Connectors need to be terminated using polish or adhesive or sometimes splicing.
  5. Determine the Power/Loss budget using factors like type of fiber, transceiver wavelength, number of connectors, length, and splices. And choose communication products keeping the link loss budget in mind.
  6. Then comes the installation. A DIYer can take help of NECA 301-2004 Standard for Installing and Testing Fiber Optic Cables or else Contractors can be hired depending upon the scale of installation procedure.

What challenges you need to surpass

Bandwidth: OM3 and OM4 fibers are the only multi-mode fibers used in 40G and 100G migrations. These fibers have 2000 and 4700 effective modal bandwidth (EMB), respectively. The challenge is to achieve a truly scalable bandwidth that can help meet the performance criteria entailed in IEEE standards.

Skewing: 0.75-ns skew is considered tolerable for 40G/100G applications. The skew causes delay of transmission across different channels thereby affecting the performance of the network badly. Skew causes connection loss while deploying the parallel optic connectivity solution and so it has to be controlled to make the connection viable for a wide range of communications applications.

Insertion loss: The insertion loss specification of the MPO/MTP connector is the challenge required to be defeated while designing data center cabling networks. To reduce the insertion loss, impeccable cleaning of fiber optic connectors is essential. Dirt, oil and moisture should be completely out of sight and only the light should be made to pass for a flawless MTP connection. Proper alignment of two fiber cores, splicing of the optical fiber connectors and dirt removal are some of the ways to combat insertion loss.

Role of MPO adapter in 40G and 100G deployments

For migrating to 40G, experts require MPO cord to replace harness cable assembly. The 40G channel is completed by linking one 12-fiber MPO trunk cable and a 12-fiber MPO cord on either end. The MPO fiber adapter is used as an interlink between the 12-fiber MPO cord and an equipment on the either side of the connection. All these MPO cables are bifurcated into two in similar arrangement to get the 100G network.



If you are looking for easy and flexible 40G and 100G deployments in a data center environment, you need to master parallel optics and employ MTP solutions that enable high density ports, flexible interfaces and scalable networks. Cozlink manufactures and supplies different fiber optic connector and data cables fully compliant with industry set standards.