More and more products are being released with single mode single fiber optics and can be perceived as being very expensive, but are they?
What is single mode single fiber?
The answer is that it is possible to transmit and receive using one strand of single mode fiber. This is achieved by using two different wavelengths – one end will transmit at 1550 and will receive at 1310 and vice versa for the other end. By using these wavelengths the signals will never collide.
How does this help?
In large networks where uptime is required for mission critical applications, throughput and bandwidth are extremely important. Utilizing and getting the most of your existing network is also very important. Take the following as an example: I have a pair of fibers using Gigabit speeds. By using the Gigabit port on your switch connected to an optical mode conversion media converter which has single mode single fiber technology I will only use one strand of fiber to achieve the same result. This allows me to save money and free up fibers for other applications.
If I want to increase bandwidth I can use two ports of my switch. Again, using single mode single fiber products and the LACP feature of the switch to group two ports together to appear as one, I have now increased my bandwidth from 1 Gigabit to 2 Gigabit. While only using 2 fibers.
Another advantage is if one strand of fiber was to fail the link would not go down. The speed would be reduced to 1 gig thus making sure your mission critical applications and uptime were guaranteed.
Although the initial outlay of the single mode single fiber products may appear to be more expensive, when reviewed against the benefits of increased bandwidth, less downtime and the utilization of your fibers it appears that in the long run it will be cheaper.