Fiber Showdown: Multimode vs. Single mode

February 4, 2016 at 8:00 AM


There are two main types of fiber optic cables, Multimode and Single mode. Depending on your application one might be better than the other to achieve optimal results. So how do you decide between Multimode or Single mode fiber optic cables? Let’s put these two side-by-side and see who comes out on top – a fiber Super Bowl, if you will.




Single mode


  • ·       Large-diameter core which allows multiple modes of light to propagate
  • ·       High capacity and reliability
  • ·       Supports distances of up to 2km
  • ·       Less expensive
  • ·       Good for transmitting voice, video and  data signals over shorter distances 
  • ·       Mostly used for data and audio/visual applications in local-area networks and backbone applications within or between buildings (campus environments)
  • ·       Smaller core diameter which allows only one mode of light to propagate
  • ·       Much higher bandwidth
  • ·       Supports distances of 100km (optics dependant)
  • ·       More expensive
  • ·       Good for transmitting streaming voice, video and data over long distances
  • ·       Typically used in long-haul network links over extended areas by telecommunications companies and cable television networks



The optics used in fiber applications are not compatible and you cannot mix Multimode and Single mode fiber between two endpoints, so you must pick only one. What you choose really boils down to bandwidth, speed and distance.


Multimode will support a maximum bandwidth of 4700 MHz/km (OM4 laser optimized) and will extend to a distance of up to 2km (@100 Mbps). Currently the maximum speed supported on Multimode fiber is 100Gbps.


Single Mode fiber can support virtually unlimited modal bandwidth as well as Terabit data rates, it can also span up to 100km without the use of a repeater. Single mode cabling is being used heavily in large data centers and in long haul broadband carrier applications.


So your choice for fiber MVP will depend on the factors listed above and your specific application.


For a deeper look at the playbooks of these two cable types and to see a handy reference diagram, check out our blog post Fiber Fun Fact: Multimode vs. Single-mode.


How it Works: Fiber Optics

October 8, 2015 at 8:00 AM


Remember when you were a kid and would tie two tin cans together with a string to create a make-shift telephone?  Now imagine a high-tech version of that using pipe instead of a string, and if you shine a flashlight down that pipe it can be seen at the other end, despite curves and twists.  Turning the light on and off would allow you to communicate via Morse code.


Essentially, this is how fiber optic cables work, but they can carry millions of conversations and billions of bits of information per second!


Fiber optic cables use light pulses to transmit data from one end to the other. A coded beam of light is sent down a glass core that is surrounded by a mirror-like covering called cladding.


The cable’s core is made up of a thin strand of glass comparable to the thickness of a human hair. The glass is so pure that it allows light to shine through even though it may be several miles long.


The cladding covers the glass core to essentially create a mirror around the optical fiber and keeps the light contained.


Data transmissions made of light pass through the core, bouncing off of the cladding until it reaches the other end of the cable, where it is received and decoded by a fiber optic transceiver.


There are two types of glass fiber-optic cables: Single mode and Multimode.


Single mode is the simplest type of fiber optic cable.  Its core is small in diameter (typically 9 microns) and carries light signals straight down the middle of the fiber core without “bouncing” off the cladding. Single mode is ideal for longer distances and higher bandwidth applications. It can send information more than 100 kilometers before a repeater is necessary and is generally used in cable TV, internet and telephone applications.


Multimode fiber optic cable is larger in diameter (typically 50 or 62.5 microns). Its optical fibers are almost 10 times bigger than those in Single mode cable and allow light beams to travel through the core by following various paths. Multimode is used to send information over shorter distances. It is more economical, easier to work with and more common for Enterprise and SMB computer networks.


 No matter which type of fiber optic cable you choose, they all posses the following characteristics


·       Very low attenuation or loss over distance

·       Immunity to EMI and RFI

·       Hard to “tap” very secure

·       Very high bandwidth handling capabilities


Originally developed for medical use, fiber optic cables have revolutionized the telephone industry and have made internet accessible to the world. The possibilities for future applications are endless.


Explore our Fiber Optic product offering and check out our informative video that explains the different types of fiber optic cable.



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