In networking contexts, "UPD" typically refers to UDP (User Datagram Protocol) , which is the underlying protocol the Discovery Tool uses to broadcast and find devices. The article below clarifies this. If you meant a specific patch file or firmware build, please verify the exact nomenclature on Ubiquiti's official portal. Ubiquiti Discovery Tool v2 (Version 4.1): The Essential UDP-Based Network Scanner Introduction For network administrators managing Ubiquiti devices, locating a specific access point, router, or switch on a congested Layer 2 network can be challenging. The Ubiquiti Discovery Tool v2 (Version 4.1) solves this by using UDP (User Datagram Protocol) broadcasts to instantly detect all compatible Ubiquiti equipment, regardless of IP address conflicts or missing DHCP leases.