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Networking Toolbox

Networking Toolbox illustration
Small tools for the arithmetic that comes up every week: subnetting, summarising routes, working out transfer times and TCP windows, decoding type-7 strings and encoding DHCP option 43. Everything runs in your browser; nothing you type is sent anywhere.
IPv4 Subnet CalculatorNetwork, broadcast, host range, wildcard and binary for any IPv4 prefix, plus a subnet splitter. Runs in your browser. Route SummarisationPaste a list of IPv4 prefixes and get the smallest set of aggregates that covers them exactly, or one covering supernet. Bandwidth & Transfer TimeHow long a file takes at a given link speed, or what speed you need to finish in time, with protocol overhead and bits-vs-bytes handled for you. Throughput & LatencyBandwidth-delay product, the TCP window a single stream needs, the throughput a given window can reach, and packets per second at line rate. Cisco Type 7 DecoderDecode (or encode) Cisco IOS type 7 passwords from a config line, and a reminder of why they should be type 8 or 9. DHCP Option 43 GeneratorVendor-specific option 43 for wireless controller discovery: Cisco WLC, Aruba, Ruckus ZoneDirector/SmartZone, UniFi, custom; output for IOS, Junos, ISC, Windows, MikroTik, FortiGate.