Cisco GLC modules are 1 Gb/s SFP transceivers: the GLC-TE and GLC-T run over copper with an RJ45 jack, the GLC-SX-MMD runs over multimode fiber at 850 nm, and the GLC-LH-SMD runs over single-mode fiber at 1310 nm for up to 10 km. Pick the module by cable type and distance, then by the brand coding your switch expects.
The four common Cisco 1G SFP modules
| Part number | Standard | Media | Connector | Wavelength | Reach |
|---|---|---|---|---|---|
| GLC-TE | 1000BASE-T | Copper | RJ45 | - | 100 m |
| GLC-T | 1000BASE-T | Copper | RJ45 | - | 100 m |
| GLC-SX-MMD | 1000BASE-SX | Multimode fiber | LC | 850 nm | 550 m on 50 um fiber, 220 m on 62.5 um |
| GLC-LH-SMD | 1000BASE-LX/LH | Single-mode fiber | LC | 1310 nm | 10 km |
Reach figures are from Cisco data sheets held in our catalog.
GLC-TE and GLC-T: copper SFP
The GLC-TE and GLC-T turn an SFP port into a standard RJ45 Gigabit Ethernet port. Use them when you need to connect copper cabling to a switch, router or firewall SFP port, for example a link to a device that has only RJ45 ports.
- Reach: 100 m over twisted-pair copper cabling.
- GLC-TE vs GLC-T: both are 1000BASE-T copper modules. The GLC-TE is the extended-temperature version, rated for a wider operating temperature range. It suits wiring closets, industrial enclosures and sites without full climate control.
- Power and heat: copper SFPs draw more power and run hotter than fiber modules. Some switches limit how many copper SFPs you can install side by side. Check your switch documentation if you plan to fill a row of ports.
GLC-SX-MMD: multimode fiber
The GLC-SX-MMD is a 1000BASE-SX module for multimode fiber at 850 nm, with duplex LC connectors.
- Reach: 550 m on 50 um multimode fiber; 220 m on older 62.5 um FDDI-grade fiber.
- Typical use: links inside a building or a campus, such as an access switch to a distribution switch.
- The "D" suffix: this module is the DOM (digital optical monitoring) version. DOM reports optical power, temperature and voltage to the switch. In our catalog, the older GLC-SX-MM is recorded as superseded by the GLC-SX-MMD.
GLC-LH-SMD: single-mode fiber
The GLC-LH-SMD is a 1000BASE-LX/LH module for single-mode fiber at 1310 nm, with duplex LC connectors.
- Reach: 10 km on single-mode fiber.
- On multimode fiber: it can run up to 550 m over multimode fiber when used with a mode-conditioning patch cord.
- Typical use: links between buildings, floors with long risers, or sites.
- Supersession: the older GLC-LH-SM is recorded in our catalog as superseded by the GLC-LH-SMD, the DOM version.
How to choose
- What cable is already installed? Copper (RJ45) means GLC-TE or GLC-T. Multimode fiber (usually aqua or orange jacket) means GLC-SX-MMD. Single-mode fiber (usually yellow jacket) means GLC-LH-SMD.
- How long is the link? Up to 100 m on copper. Up to 550 m on 50 um multimode with SX. Up to 10 km on single-mode with LH.
- Match both ends. A link needs the same standard on each end: SX to SX, LX to LX. You cannot connect an SX module to an LX module.
- Check the port speed. These are 1G modules. Many SFP+ ports accept 1G SFP modules, but not all. Check the switch or adapter documentation.
- Choose the temperature rating. Use extended-temperature modules, such as the GLC-TE, in hot or uncontrolled spaces.
For 10G links, see our guide to 10G SFP+ optics. For form factors and fiber types in general, see transceivers and cables.
Equivalent 1G SFP modules from other brands
Each switch brand sells the same standards under its own part numbers. If the other end of your link is a different brand, each end needs a module coded for its own device.
| Standard | Cisco | HPE Aruba | Juniper | Arista |
|---|---|---|---|---|
| 1000BASE-T copper | GLC-TE, GLC-T | JL747A | EX-SFP-1GE-T | SFP-1G-T |
| 1000BASE-SX multimode | GLC-SX-MMD | J4858D, JL745A | EX-SFP-1GE-SX | SFP-1G-SX |
| 1000BASE-LX single-mode | GLC-LH-SMD | J4859D, JL746A | EX-SFP-1GE-LX | SFP-1G-LX |
Exact reach figures vary by brand. For example, the Aruba J4858D lists 500 m on 50 um OM2 fiber, while the Cisco GLC-SX-MMD lists 550 m on 50 um fiber. Check the figure for the module you buy if your link is near the limit.
OEM vs compatible modules
Every SFP stores vendor data in an EEPROM. Many Cisco switches read it and check that the module is a Cisco or Cisco-coded part.
- OEM Cisco modules carry Cisco part numbers and match Cisco's support lists. Choose them for systems under Cisco support contracts.
- Compatible modules are built to the same IEEE standard and coded to identify as compatible with your switch. They are a common choice for out-of-warranty switches and large deployments.
- Generic modules from optics makers, such as the Finisar FCLF8521P2BTL copper SFP, suit platforms that accept any standards-compliant module.
Tell us the switch model at each end of the link and we will match the coding.
Checklist for your request
- Switch, router or adapter model at each end.
- Cable type: copper, multimode or single-mode fiber.
- Link distance.
- Operating environment: standard or extended temperature.
- OEM or compatible coding.
- Quantity, including spares.
Browse all transceivers or Cisco products, and add the modules to an RFQ. For a part number we do not list, use Source a Part. We reply within 1 business day.
FAQ
What is the difference between GLC-T and GLC-TE?
Both are 1000BASE-T copper SFP modules with an RJ45 jack and 100 m reach. The GLC-TE is the extended-temperature version.
Can I use a GLC-SX-MMD on single-mode fiber?
No. The GLC-SX-MMD is for multimode fiber. For single-mode fiber, use the GLC-LH-SMD.
What does the "D" in GLC-SX-MMD and GLC-LH-SMD mean?
It marks the DOM (digital optical monitoring) version, which reports optical power, temperature and voltage to the switch.
How far can a GLC-LH-SMD reach?
Up to 10 km on single-mode fiber. On multimode fiber it can reach up to 550 m with a mode-conditioning patch cord.
Will a GLC-TE work in a 10G SFP+ port?
Many SFP+ ports accept 1G SFP modules, but support depends on the switch model and port. Check your switch's transceiver compatibility list.