Cisco Company was founded in 1984 by Leonard Bosack and Sandy Lerner. Cisco specializes in the design, manufacture, and sale of network equipment. It is one of the first companies to sell commercially successful routers that supported multiple network protocols. One of its most successful products is the Cisco SFP GLC-LH-SM, which is a fiber optic transceiver that allows users to more easily upgrade or maintain a network. Users can replace a single SFP module without having to replace the entire board with other modules.

Cisco SFP, also known as Small Form Pluggable, is the enhanced version of GBIC (Giga Bitrate Interface Converter) with LC interface and half the size of GBIC. SFP saves space and has a working distance ranging from 500 meters to 100 kilometers. You can find SFP connectors on Ethernet switches and network interface cards. Its low-cost, low-profile nature and ability to provide multiple connections to many different types of fiber optics provides flexibility for most equipment.

Cisco SFP transceivers come with a large selection of transmitters and receivers. For each link there is a dedicated transceiver that allows users to select and provide the required optical reach over the type of optical fiber available, such as multimode fiber or single mode fiber. Optical SFP modules are available in the following categories:

For multimode fiber-

• SX – 850 nm for a maximum of 550 m at 1.25 Gbit/s (Gigabit Ethernet) or 150 m at 4.25 Gbit/s (Fiber Channel)

For single-mode fiber

• LX – 1310 nm for distances up to 10 km
• BX – 1490 nm/1310 nm also for distances up to 10 km
• 1550nm 40km (XD), 80km (ZX), 120km (EX or EZX)

The Cisco Model GLC-LH-SM SFP is a transceiver that operates at a wavelength of 1300nm and can be used with both multimode and singlemode fibers. Its small size makes it flexible and easy to use. Its key features are:

• Dual operating data rate of 1.25 Gbps/1.063 Gbps
• 1310 nm FB laser and PIN photodetector for 20 km transmission
• LC interface
• Digital Diagnostic Monitoring
• Compliant with SONET OC-24-LR-1 and RoHS
• Single +3.3V power supply
• Operating temperature: standard from 0 to +70 degrees C and for industrial use from -40 to 85 degrees C

Its applications are the following:

• GigabitEthernet
• Fiber Channel
• Switch to exchange interface
• Switched backplane applications
• Router and server interface
• Other optical transmission system