The Application and Development of Optical Fiber Technology

Data center cabling system needs to continuously upgrade the bandwidth for the fast-growing network (such as the network core layer, convergence layer network and SAN storage network) transmission applications ahead of paved roads, and the use of optical fiber transmission can provide protection to continue to explore the bandwidth potential. Compared with single-mode fiber, due to Multimode Fiber Patch Cable lower active + passive integrated technology costs, will lead to multi-mode fiber has an absolute advantage in the application of the data center, medium and large data centers more than 85% of the fiber optic cabling system uses a multi mode fiber. August 2009, TIA formally approved OM4, a new category EIA/TIA492AAAD standard multimode fiber launch offers good prospects for the future large-scale application of multimode fiber, multimode fiber from OM1 to OM2, optimizing the use of VCSEL laser after a full technical OM3 to OM4,vthen developed four stages, the bandwidth also progressively increase.

Following the June 2010 IEEE802.3ba new Ethernet 40G/100G standard release, multimode fiber applications in the data center will open a new page, 40G and 100G high-speed transmission is no longer just rely on the use of single-mode high cost of WDM serial transmission, the new generation of Ethernet 40G/100G OM1 Multimode Fiber and OM4 standards will adopt a multi-channel parallel and multi-mode fiber transmission mode, compared to single-mode WDM way transmission mode, this multi mode on 40G/100G total cost (including active devices, optical modules, passive components) are only single-mode system 1/3 and 1/10, visible multimode advantages are obvious. Applications market trends is often by cost and price factors to drive mode with which technology can take big decisions largest application in the market.

40G multimode fiber transmission mode supports 10Gbps use each pair of rate 4 * 10Gbp = 40Gbps, need to use all four fibers send and receive 8-core optical fiber, 100G uses 10 fibers each sending and receiving 10 * 10Gbps = 100G , a total of 20 core optical fiber, using the standard MTP / MPO multi-pin connector system will be able to transfer to better support the next generation optical network 40G/100G, 40G transmission mode within 12 core MTP / MPO connectors on each side take four core outermost transmission, intermediate 4-core is vacant, and 100G transmission mode is the use of two 12-core MPO MTP Fiber take the middle 10 connector pin for transmission, if using MTP / MPO high-density 24-pin connector, complete the reception and transmission of 100G on a 24 core MTP / MPO connectors. When 100G transmission, both sides of the core of every 12 cores each one is vacant.

As the standards and application standards of the new generation 40G/100G optical fiber technology has released, it has a definite direction about the Fiber Patch Cables types for data center planners. OM3 and OM4 fiber will become the mainstream data center, OM4 fiber were used in 40G/100G corresponding distance transport protocol and application support, although 40G/100G transmission distance of multimode and single-mode fiber can not be up to 10KM or 40KM comparison, but in the data center indoor application environment, according to statistics of small and medium data centers more than 90% of the fiber link length is less than 100 meters, a large data center more than 70% of the fiber link length is less than 100 meters, more than 80% of the length is less than 125 meters, multimode meet the needs of the vast majority of the link, with the upgrading of network equipment and technology, in the future to support multi-mode fiber transmission distance may increase further.

Transport protocol type and fiber types support the transmission distance: 40GBase-SR4850nmVCSELOM3 Fiber 100m 40GBase-SR4850nmVCSELOM4 Fiber 120m 100GBase-SR10850nmVCSELOM3 Fiber 100m 100GBase-SR10850nmVCSELOM4 Fiber 125m Standard ANSI/TIA568C.3 North American Telecommunications Industry Association released in June 2008 for Fibre Channel connection to MTP / MPO connector consisting of multi-core defines three fiber connection modes, respectively TYPE-A, TYPE-B, TYPE -C, and below at 10Gbps transmission applications, the use of an Ethernet device port duplex mode, MTP / MPO trunk link will eventually be converted into a duplex type connectors such as LC, SC, etc., while in the state 40G/100G if the device port directly connected with QSFP MTP / MPO connectors, typically by several optical fibers, whether connect the cable, either of which is connected to the middle of the optical fiber connection TYPE mining equipment terminal and the device-side 40G/100G channel connection between the need to form the final model state TYPE-B, the equipment sending and receiving ends of the channel correspond to each other, otherwise it will not communicate properly.