Alphabet soup of transceiver abbreviations or what means what?

Some of our customers or even we got lost in alphabet soup of abbreviations in transceiver industry. Here is a short recap of what means what:


SFP (Small Form-factor Pluggable)

Transmission distances of SFP transceiver vary from the 100m till 120km and each of them use a different combination of symbols which is common in the industry to describe it.


Copper SFP

This kind of  transceiver supports copper connection over CAT5 cable maximum up to 100m and it has RJ45 connector. Copper module are used for different places today’s networking where existing copper connections still available.



SX (Short Wavelength) operates over MMF (multimode fiber) up to 550m with LC connectors. SX modules work with 850nm lasers. These standard transceivers are popular for networks inside the one building. As MMF core is thicker, it allows to reach higher speed at the short distance. These transceivers are more affected by modal dispersion because light rays have different paths through the fiber and it arrives at different times at the other end. This is the reason why distance is limited.



LX (Long Wavelength) supports link up to 10km over SMF (single mode fiber) or 550m on MMF.  SMF LX works at 1310nm, it is more affected by waveguide dispersion, and it is more affected by micro bends, twists and stress in the fiber. These modules use for Ethernet switches and routers to connect it in the different buildings.



EX (Extended Wavelength) can reach a longer distance up to 40km over SMF and 1310 or 1550nm. There are different of networking places where these distance module are used. For example most popular are for Internet Service Providers, Gigabit Ethernet Communications, Ethernet and Data Center Networks and other optical links.



ZX also stands for Extended Wavelength but it can reach 80km over SFP and works with 1550nm laser. These transceivers use in similar networks where 40km optical modules only distance between devices are longer.

One more option is EZX standard with extended distance up to 120km.


BX-D and BX-U

These optical transceivers use one optical fiber instead of two for standards which are mentioned above. It is a cost-effective solution for Data Centers and other infrastructure. BIDI SFP optical modules must be matched in pairs because there is one port only for transmitting or receiving. These optical transceivers use SMF from 10 to 120km to support bi-directional links.


SFP+ (Small Form-factor Pluggable+)

There are many common distance types for 10G SFP transceiver in the fiber optical networks. Some of them are mentioned below.


Copper SFP+

Copper SFP+ common for communications links which requires 10Gigabit over Cat6a/7 cables and RJ45 connector. Transmission distance depends on the speed, for example, it can reach 30m at 10Gb/s. Advantage of these transceivers that it can be compatible with legacy networks and plan copper network using existing ports. Also copper cables are less expensive than fiber cables.



SR (Short Range) is very popular optical transceiver for high speed in the short distance (till 300m) via OM3 fiber and operating at 850nm. It is option for Data Centers, Enterprise Networks, Internet Service Providers and for other optical links.



LR (Long Range) helps to connect to network equipments from the distance up to 10km. LR unlike SR connected over SMF and use 1310nm laser. Transceivers are suitable for Data Centers, Enterprise and Internet Server Provider networks. As LR has no minimal distance then it can be used for short connections over SMF.



LRM (Long Reach Multimode) operates with the same 1310nm laser as LR but distance is only till 220m over MMF which is enough for LAN networks inside the building. This is popular for the high speed in the short distance where legacy OM1 fiber is used.



ER (Extended Range) works in distance up to 40km on SMF and 1550nm laser. These optical transceivers are in different applications such as for Data Centers, Enterprise and Internet Service Providers networks.



ZR transmission distance reach till 80km over SMF with 1550nm laser. Modules are used for optical network applications.


If you see when optical modules part number ends with -X, that means these transceivers operates at industrial temperature range from -40°C to 85°C. There is no other difference between industrial and commercial version where temperature range is restricted from 0°C to 70°C. Optical modules will not work in minus degrees or higher than 70°C.

Cisco introduced S-Class modules, for example, SFP-10G-SR-S which is budget version of SFP-10G-SR due the less expensive. These S-Class transceivers are invented to offer main common features to the Enterprise and Data Center applications. Generally, these modules supports only Ethernet, not Optical Transport Network (OTN) but physically it looks the same as non S-Class version.