ScanLAN - Scan a local network for devices, ping and check for open ports. Monitor internet connection for issues

ScanLAN is a Windows-only network monitoring desktop application written in Go that gives you a single-pane view of what's happening on and around your machine's network. It's organized as a tabbed window with four primary monitoring surfaces — LAN, Traceroute, DNS, and Bandwidth.

The LAN tab continuously discovers devices on the local subnet (ARP-based scan, ICMP ping aging, port-scan results, and mDNS printer-service queries every 60 seconds), then renders them with IP, MAC, hostname, device-class guess, ping success/fail counts, history sparkline, and discovered open ports. You can mark IPs as "watched" and have the app beep on failure.

The Traceroute tab discovers the path to a target (default 8.8.8.8), then pings every hop once per second, surfacing per-hop loss%, last/min/avg/max RTT, jitter, stddev, P50–P99.9 percentiles, ASN/org lookup, and a history sparkline; it auto-rediscovers every 5 minutes and retries every 30 seconds if the previous discovery didn't reach the target.

The DNS tab probes the locally-configured plus a curated list of public resolvers once per second using rotating test domains, exposing the same RTT/percentile statistics as the Traceroute tab, plus a manual "resolve domain or URL" lookup field.

The Bandwidth tab samples interface counters. A real-time graph at the top shows in/out throughput. Spike alerts (≥5× the 5-min average) post to the Status log.

The Adapters tab shows IPv4/IPv6/CIDR/Gateway, MAC, MTU, link speed, throughput min/avg/max, totals, disconnect counter, time connected/disconnected, and full Wi-Fi details (SSID, AP BSSID, channel, frequency, auth, radio, signal%, RSSI). It also draws an RSSI-over-time graph.