SFP SC and LC connectors Transceivers Defined and Analyzed in Detail

Fiber optic transmission technology has evolved over the years to meet the requirements of high bandwidth and fast data applications. This becomes quite evident from the increasing use of fiber optic devices in data centers, LANs, MANs, and so on. Fiber optic cables and fiber optic connectors form the base of such fiber optic networks. Owing to their increasing popularity there is a wide range of cables and connectors to choose from. Of these two elements, fiber optic cables are the most discussed ones, while connectors are the least discussed ones. The topic of fiber optic connectors is comprehensive and may span across documents. This white paper primarily focuses on two popular fiber optic connectors – SFP SC and SFP LC transceivers, which have gained immense popularity in recent years.

LC and SC Connectors

SFP Transceivers and Their Role in Modern Communication Applications

SFP is an abbreviation for small form-factor pluggable transceiver, which is an interface module used for communication applications. This transceiver can receive and transmit data and is used in both copper and fiber optic cables. In simple terms, the transceiver is a hot-swappable device that plugs into a port of a network device. These transceivers can support different communication standards such as Gigabit Ethernet, SONET, and fiber channels. SFP transceivers can be interfaced with LC and SC connectors. This interfacing lends them the name SFP LC transceiver and SFP SC connector. The next section gives you a basic idea of these connector types.

What are LC and SC Connectors? Know By Definition

  • SC Connectors: SC is an abbreviation for Subscriber Connector. These connectors are also known as Standard Connectors or Square Connectors. The connectors were first introduced in the 1980s by the laboratories of Nippon Telegraph and Telephone (NTT) and were the first to enter the market after ceramic ferrules. SC connectors stand out due to their push and pull design featuring a locking tab. These connectors are widely chosen for their inexpensiveness and reliable design. SC connectors are suited for telecommunication and data transfer applications, and are employed in passive and point-to-point optical networking.
  • LC Connectors: Developed by Lucent Technologies, which is now owned by Nokia, the Lucent Connectors are comparatively newer and also use the push and pull mechanism. At times, these connectors are also referred to as the smaller version of SC connectors as they employ latches with small ferrules. The LC connectors initially received a slow response in the market due to the high licensing fees involved; however, today they are widely used in data applications and high-density patch applications.

SFP LC VS SC Connectors Key Differences and Similarities Discussed

Although LC and SC connectors are quite similar to each other in many ways, they differ in many other ways. The following pointers would help you understand it better.  

  • Size of Ferrule: The connectors are differentiated based on two different sized ferrules. The SC connector is equipped with a 2.5mm ferrule and LC connector with a ferrule of 1.25 mm. This along with a compact connector housing makes LC connector smaller than SC. This smaller footprint explains its increasing use in dense rack panels. LC connectors are a common sight in central offices with high packing density.
  • Ease of Use: The SC connectors feature a snap-in connection that enables quick patching of cables into wall or rack mounts. Two SC connectors can be clipped using a reusable duplex holding clip to form a duplex SC connector. LC connectors feature a latch mechanism, which also ensures efficient removal as well as insertion. LC connectors can be easily grouped into a locking clip and keyed arrangement, which makes it popular.
  • Reduced Rearrangement: LC connectors are equipped with anti-snag latches, which helps reduce the rearrangement caused due to cross-connection.
  • Insertion Loss and Return Loss: Insertion loss is the ratio of power that is incident to the power that is transmitted by a connector or device. However, return loss refers to the ratio of power that is incident to the ratio of power that is reflected by a connector. LC connectors and SC connectors both have the same insertion and return loss.
  • Performance: Both SC and LC connectors assure efficient, fast, and consistently strong performance, which leads to efficient data communication. Both these connectors assure interference-free data transmission.
  • Years of Utility: Of these two connectors, the SFP SC transceivers are the oldest ones, as discussed before. These transceivers are quite popular and have been widely used over the years. However, SFP LC transceivers are gaining traction, too.
  • Time Saving: As LC connectors are half-sized than their SC counterparts, which helps saves time for installation.
  • Repeatability: Both LC and SC connectors possess polarization feature, which helps in maintaining or receiving direction, and ensures high repeatability.

Knowing the subtleties of LC and SC connectors would definitely help; however, you need to know about a few fiber optic devices that add value to any network. These devices serve as a base for connectors. Read the next section to know about these devices.

A Few Important Fiber Optic Devices to Connect LC and SC Connectors

The choice of LC and SC connectors will entirely depend on your application requirements. However, the following are a few devices that you may need while using these connectors.

  • Media Converters: These devices enable signal conversion, and are largely used in networks that use both copper and fiber optic cables. There are copper to fiber, fiber to copper and fiber to fiber media converters to choose from. Nowadays, these converters are equipped with SFP transceivers, and they support LC and SC connectors.
  • Network Switches: They are the most important network hardware, which connects different devices in the network. There are different types of network switches to choose from. Industrial switches, PoE switches, hardened switches, and so on are a few popular ones. Today, it is quite easy to find network switches with LC and SC SFP transceivers.
  • High Definition Transmitters and Receivers: High definition serial digital interface (HD-SDI) is a standard for digital video transmission lines. These enable the transfer of unencrypted and uncompressed video and audio signals. HD-SDI converters, HDMI video systems, and HD-CVI, HD-AHD, and HD-TVI installation kits are examples of High Definition transmitters and receivers.

Conclusion

Fiber optic communication is set to grow significantly in the years to come. It is making its presence felt in industries like defense, healthcare, railways, oil and gas, and so on. The choice of the right cables and cable connectors as well as fiber optic devices is important to ensure a precise connection. The pointers in this white paper will help when it comes to choosing between the SFP SC and SFP LC transceivers. However, if you are unsure about the right fiber optic devices, you can always get in touch with the team at VERSITRON, which is a market leader in fiber optics. The company provides various types of fiber optic devices such as copper to fiber media converters, fiber optic network switches, high definition transmitters and receivers, and so on.