What's the differences between SM & MM optical fiber and it's application scenarios?

  • SM is single mode

  • MM is multi mode

  • SM has 9 micrometer core diameter

  • MM has 50-62 micrometer core diameter

  • SM used in long distances transmission

  • MM used for short distances transmission

  • SM used in WDM technology ( specially DWDM )

  • SM should use Single mode SFP

  • SFP is small form factor pluggable and it’s the optical module that convert optical to electrical and vice versa

  • We can use 1310 and 1550 nm in single mode

  • We can use 850 nm in multimode

  • SM has higher immunity to modal dispersion

  • ITU standardize G 652 , G 653 and G 655 to work in single mode optical

  • G 652 and G 655 is the most common single mode optical fiber used in DWDM technology

  • G 653 can be used in SDH

  • We can’t use G 653 in DWDM because it’s zero dispersion point is in 1550 nm and it can lead to four wave mixing

Credits: :point_down: