We visualize kilometers of optical fiber networks connecting highly remote locations when we come across a notion of fiber optics or optical fiber links like SFP cable. And, many questions arise when it comes to building a network:
- What is the distance between SFP modules?
- Difference between a single-mode and a multi-mode cable?
- Which type of cables suits an SFP module?
- Which type of fiber optics to select?
The major benefits of optical fiber networks include high interference immunity, protection against unauthorized access, and an increase in transmission distance.
The principle behind it is based on the light that is used for the signal transmission. At the connection boundary of the DAC cable, the light is transferred through the core made from a special polymer with transceivers.
Within a type of optical fiber, the main difference between various SFP modules lies. That is the reason why while selecting a module, it is required to decide on a fiber optics type first.
Single-Mode optical modules
They are mainly used with a single-mode (SM) cable, typically, of 9/125 standard. Here there is the use of another technology, the laser is used as a light source, and radiation spreads along with the optical fiber in one mode, so that the data transmission distance reaches 120 km.
With a WDM technology, there also exist SFP modules, in which the signal receipt and delivery are done through a single core (using one connector), but at different wavelengths. While building networks this either reduces the number of cores or saves money in projects where the number of cores is limited by the budget. In this technology, there is the use of only a single-mode optical fiber. For organizing a connection, there is the use of two paired modules with each having different (opposite) wavelengths of a receiver or a transmitter.
Multi-mode optical modules
They are specifically designed for application with a multi-mode (MM) cable or AOC cable, typically of 50/125(ОМ2) standard or 62,5/125 standard. Modules provide support to data transmission at a rate of up to 10 Gb on waves with a thickness of 850 nm or 1320 nm. For data transmission, the energy of light is used and a light-emitting diode serves as a source. Several radiation modes spread along with the optical fiber, each at its unique angle. The main disadvantage is that there is a data transmission distance of up to 550 meters.
