Whether to deploy single-mode fiber (SMF) or multimode fiber (MMF) optics is still a hot topic in the industry. From 1 Gigabit Ethernet to 100 Gigabit Ethernet, people look forward to receiving more bandwidth, higher speed in a more cost-effective cabling manner. The cost between MMF vs SMF Optics, as one of the key considerations, is highly concerned by many data center operators.
Optics for SMF vs MMF are usually a bit more expensive. Take FS.COM for example, the following table lists the list prices of Cisco compatible SMF optics and MMF optics from 1Gbps to 100Gbps. With the increase in speeds, the gap between the optics price is great.
|Multimode SFP||Cisco GLC-SX-MMD Compatible 1000BASE-SX SFP 850nm 550m DOM Transceiver||US$ 6.00|
|Single-mode SFP||Cisco GLC-LH-SMD Compatible 1000BASE-LX/LH SFP 1310nm 10km DOM Transceiver||US$ 7.00|
|SMF SFP vs MMF SFP||LH vs SX||US$ 1.00|
|Multimode SFP+||Cisco SFP-10G-SR Compatible 10GBASE-SR SFP+ 850nm 300m DOM Transceiver||US$ 16.00|
|Single-mode SFP+||Cisco SFP-10G-LR Compatible 10GBASE-LR SFP+ 1310nm 10km DOM Transceiver||US$ 34.00|
|SMF SFP+ vs MMF SFP+||LR vs SR||US$ 18.00|
|Multimode QSFP+||Cisco QSFP-40G-SR4 Compatible 40GBASE-SR4 QSFP+ 850nm 150m MTP/MPO DOM Transceiver||US$ 55.00|
|Single-mode QSFP+||Cisco QSFP-40G-LR4 Compatible 40GBASE-LR4 and OTU3 QSFP+ 1310nm 10km LC DOM Transceiver||US$ 340.00|
|SMF QSFP+ vs MMF QSFP+||LR4 vs SR4||US$ 285.00|
|Multimode QSFP28||QSFP28 Cisco QSFP-100G-SR4-S Compatible 100GBASE-SR4 850nm 100m Transceiver||US$ 400.00|
|Single-mode QSFP28||QSFP28 Cisco QSFP-100G-LR4-S 100GBASE-LR4 1310nm 10km Compatible Transceiver||US$ 2800.00|
|SMF QSFP28 vs MMF QSFP28||LR4 vs SR4||US$ 2400.00|
|Note: 100G PSM4 transceiver for up to 500m costs US$ 750.00 (SR4 vs PSM4: US$ 350.00). 100G CWDM4 transceiver for up to 2km costs US$ 1350.00 (SR4 vs CWDM4: US$ 950.00).|
In general, for fiber type itself, SMF is a bit expensive than MMF. But for 40/100G cabling, the cable price mainly depends on what optics you use. For instance, if you use SMF optics with LC interface and MMF optics with MTP interface, that would be different. Because the LC terminated cables are much cheaper than the OM3/OM4 MMF MTP cables. However, MMF is for short reach while SMF is usually for long reach. Thus, the total cable cost also depends on the actual transmission distance.
For any links outside of a data center or a server room, it is usually recommended to deploy single-mode module, due to having more bandwidth and further distances. And for short reach interconnection or small data centers, multimode fiber module is preferred by many users due to its lower cost. In my opinion, SMF may be better in 1G and 10G applications or for the newly-built data center with the consideration of future-proof. Because the costs of optics and cables are close enough between SMF and MMF. And for higher speed, such as 100G, single-mode optics like PSM4 and CWDM4 are ideal for use for the large data center. Certain larger data center operators have chosen to forgo MMF altogether. Microsoft, for one, has said it will deploy SMF exclusively in its data centers. Actually, no matter MMF or SMF, what the best is suitable. So, MMF vs SMF, which is your choice?