OM3 specifies an 850-nm laser-optimized 50-micron cable with a effective modal bandwidth (EMB) of 2000 MHz/km. It can support 10-Gbps link distances up to 300 meters.

Unlike its predecessors both OM3 and OM4 utilizes lasers as a light source in order to support 10G, 40G, and 100G Ethernet. OM3 is capable of covering distances up to 300 meters. OM3 uses fewer modes of light thus enabling increased speeds, it is able to run 40GB or 100Gb up to 100 meters utilizing an MPO connector. OM3 is generally used in larger private networks. OM4 can cover distances up to 550 meters. OM4 can run 100Gb up to 150 meters using an MPO connector. It is commonly used in high-speed networks, data centers, financial centers, and corporate campuses.

OM3 vs OM4 Distance

The transmission distance of OM3 and OM4 fiber cables varies when they are applied to Gigabit, 10GbE, 40GbE and 100GbE applications. You can check the maximum transmission distances of OM3 and OM4 under different transmission speeds in the below figure.

OM4 fiber distance is longer than OM3 fiber distance based on 10, 40 and 100 Gb/s. But the maximum transmission distance of OM4 under 10G remained controversial. As a rule of thumb, it is recognized as 400 m. But it still can achieve up to 550 m if the OM4 fiber has an ultra high quality.

       1.25G SFP 1550nm 120KM

What is SFP Connector?

SFP connector or SFP plug is another name of SFP as SFP (small form-factor pluggable) is a compact and hot-pluggable interface connector. The SFP connector module functions as the intercommunication media between the network devices and cables to achieve photoelectric and electro-to-optical conversion. SFP interface is commonly used in SFP port network equipment such as Ethernet switches, firewalls, routers, network interface cards (NICs) for both data communication and telecommunication applications.

Figure: the optical interface of the 1000BASE-SX SFP connector module is located at the side of the dust cap. Once unplug the cap, will you see the optical interface.

According to transmission media, there are SFP copper connectors and SFP fiber connectors. Copper SFP uses an RJ45 SFP connector interface, whereas fiber SFP uses SFP lc connector, SFP sc connector, and SFP MTP/MPO connector interface as typical ones. According to the SFP forms, different SFP form factors often utilize corresponding SFP connectors.

The table below shows the SFP connector interface types for different SFP types.

What Type of Connector is Used with an SFP Port?

SFP ports are frequently found in Ethernet network switches. These switches with 1G SFP ports as the major functional switch ports are called gigabit SFP switches.

SFP port on SFP switch supports both SFP copper connector and SFP fiber connector while RJ45 port can only take copper SFP module RJ45 connector. SFP connector types that 1G SFP port can take are RJ45 SFP connector, SFP lc connector, SFP sc connector.

FAQs about SFP Transceiver

Can We Use SFP Hardware in SFP+ Slots?

In many cases, the SFP+ port accepts SFP optics, but the speed will be down to 1G instead of 10G. However, SFP+ optics can not be plugged into the SFP port, because SFP+ does not support speed under 1G. In addition, almost all SFP+ ports on Cisco switches can support SFPs, but many SFP+ ports of Brocade switch only support SFP+ optics.

Can I use a 1000base-LX sfp for 1000base-SX fiber?

Generally, they are not interchangeable. 1000Base SX and LX are two optics standards with different operation wavelengths.1000Base LX SFP transceiver usually operates at 1310nm and uses single-mode fiber to connect, while 1000Base-SX usually is 850nm SFP and works with multimode fiber.

Can you aggregate multiple SFP ports?

Of course, you can. Link aggregation provides benefits like increased bandwidth, redundancy, and load-balancing. That will ensure that one link can immediately switch to a second available link when it fails. Therefore, aggregation on SFP ports is critical for enterprise networks where performance and security are more important. But note that, before connecting the SFP ports, please make sure that the switches have been configured for link aggregation. Otherwise, it will cause network loops.