Since 1970’s, the fiber optic cabling has been revolutionizing the telecommunications field by enabling transfer of data packets further and faster than ever before.There are two types of fiber that was developed and is continued to be used in communications today: Singlemode and Multimode fiber.
Singlemode optical fiber (SM) has a smaller core diameter which forces all the energy in a light signal to travel in the form of a single mode thus dramatically increasing the bit rate over distance.Due to its laser based focused light source, the SM fiber requires more expensive and precise electronics for data transport.
In contrast, the multimode fiber has a larger diameter core for light path than SM fiber.Therefore, light propagates in these fibers in the form of multiple modes, each taking a slightly different path through the fiber and traveling at a slightly different velocity for a given fiber length.The Multimode optical light source is based on cheaper LED’s and electronics making MM fiber networks much cheaper optical connectivity solutions. However, the low light concentration makes this application fit for only short distances. This white paper further discusses the possibility of extending the MM fiber capability to up to 2km with PacketLight’s WDM product suite.
Types of Multimode Fiber
There are two main types of multimode fiber used today in premise networks: 62.5µm multimode fiber (OM1), and 50µm multimode fiber (OM2).62.5µm and 50µm refer to the diameter of the fiber core carrying the light signal.Originally, 50µm OM2 fiber was widely utilized for both long and short reach applications.Only in 1980,’s after the introduction of single mode fiber did the shift happen to use MM fiber in distances between 300meters to 2km.Such distances were prominent in applications for office buildings and campus backbones.
However, OM2 fiber was not sufficiently reliable for distances of 2km.Therefore, in 1985 62.5µm OM1 MM fiber was introduced, which could reach distances of up to 2km with 10Mb/s of data rate.
While 62.5µm OM1 multimode fiber was sufficient for transferring 10Mbps of data signal at 2km, in today’s higher-bandwidth backbone protocols, it has become much more limiting.Today, MM fiber’s physical characteristics allow transport to distances of maximum 550m depending on protocol and type of fiber.
Today’s distance and bandwidth requirements have forced the customers to look to more expensive single mode fiber solutions and cabling, driving them to replace their existing MM infrastructure and electronics. PacketLight offers a simple cost effective migration / solution of using the existing multimode fibers and upgrade the infrastructure for today’s high rate and capacity data transport challenges without replacing the fiber infrastructure
Extending multi-mode fiber
With PacketLight’s CWDM and DWDM products, the customers with already existing MM fiber have options to keep using their existing fiber and maximize its utilization.PacketLight’s WDM solutions makes it possible to extend MM fiber capabilities beyond the 550m limitations of the 62.5µm (OM1) multimode fiber to 2km or more depending on fiber quality and service type.The services that can be transferred are 10GbE as well as sub-10G (including GbE and 1/2/4G Fibre Channel protocols).Additionally, PacketLight’s WDM equipment allows the user to multiplex more than one 10G or sub-10G services over the same MM fiber infrastructure.Extending MM fiber capabilities adds ROI to the user’s infrastructure and saves significant operational expenses, thus freeing up valuable resources.
.jpg)
Multimode fiber has been widely used in office buildings and campus applications for transferring 10Mbps.However, the reach on MM fiber has maxed out at 2Km or less.In today’s high bandwidth and high speed requirements, this distance has further diminished to 550m or less.However, with PacketLight’s CWDM and DWDM products, the distance can once again be extended to 2Km or over transferring 10GbE as well as sub-10G services and provide significant uplift for the MM fiber install base. In addition, multiple services can be multiplexed into one MM fiber, thus further maximizing the existing client infrastructure.
| 
.jpg)
