Discovery

What it does: finds the devices on your local network. It quietly pings every address in your subnet (a "sweep") and lists the ones that answer — your "who's on my network right now?" tool. For each device it also tries to look up a name and guess what KIND of device it is (switch, router, Wi-Fi access point, printer, phone, server, camera, PC, laptop, IoT gadget, media player), and it saves the list to Inventory so you can compare later.

What you need: just to be connected to the network you want to scan — no credentials, no setup. By default it opens on the subnet of the network adapter that holds your default gateway (a physical Ethernet / Wi-Fi adapter before a VPN or virtual one): that adapter's own range when it is a /24 or smaller, otherwise the /24 around this machine (254 addresses like 192.168.1.1–254). You can point it at another range.

Safe to run: generally yes — it only sends small pings, changes nothing. But it IS active traffic, so on a monitored corporate network it can trip an "unusual scanning" alert. Only scan networks you're allowed to.

What to expect / reading results: after a few seconds you get a row per device that answered — its IP address, a name (or "—" if it has none), its MAC address and the vendor that owns it, the device-type guess, and the reply time. Export CSV (and the result bar's Save as… CSV) carries IP, hostname, RTT, then MAC, vendor and type. Vendor names come from a table bundled with the app; tick "Look up unknown vendors online" before a sweep to also ask api.macvendors.com about prefixes it doesn't know (only the 3-byte prefix is sent — outside your network; off by default). Two things to know: (1) a device NOT showing up doesn't prove it's off — some devices are set to ignore pings, so they're there but silent. (2) The device-type icon is a best guess from the hardware maker; it can be wrong for an unknown or privacy-randomized device, so treat it as a hint, not proof. See also Topology (the same scan drawn as a map) and ARP table (IP↔hardware-address pairs).

Services (mDNS): optional, off by default (the checkbox is remembered). After the sweep, Discovery also asks the local link which mDNS / DNS-SD (Bonjour) services are advertised — printers (_ipp._tcp), SSH (_ssh._tcp), web UIs (_http._tcp), file shares (_smb._tcp) and so on — and lists each one's type, instance name, host, address, port and TXT details in the Services tab. It sends a few multicast queries to 224.0.0.251:5353 and listens about 3 seconds; it only sees your own link (mDNS doesn't cross routers), even if you swept another subnet. Read-only, nothing is sent anywhere else. It often finds devices that ignore pings. Save to inventory still saves the swept hosts; the service rows are for reference. In demo mode it shows the sample network's services and sends nothing.