SFP 10G SR (Short Range) and SFP 10G LR (Long Range) are both types of 10 Gigabit Ethernet (10GbE) optical transceivers used in networking equipment to provide high-speed connectivity. The main difference between them lies in the distance they can cover:

1. SFP 10G SR (Short Range):

• Distance: Typically supports distances up to 300 meters over multimode fiber.

• Fiber Type: Designed for use with multimode fiber cables.

• Application: Typically used for shorter-distance connections within data centers or campus networks.

2. SFP 10G LR (Long Range):

• Distance: Supports longer distances, usually up to 10 kilometers or more, over single-mode fiber.

• Fiber Type: Designed for use with single-mode fiber cables.

• Application: Suited for longer-distance connections, often used in metropolitan area networks (MANs) or for connecting buildings over longer distances.

In summary, the key difference is the range or distance each transceiver type can cover, with SR being optimized for shorter distances using multimode fiber, and LR being designed for longer distances using single-mode fiber. When selecting between SR and LR, it's essential to consider the specific networking requirements and the distance between the devices you are connecting.