jubiar 

Fast, fully offline MAC address to vendor lookup. Parses MAC addresses in any format (colon, hyphen, dot/Cisco, bare, spaced), validates them, and resolves the hardware vendor from the complete embedded IEEE... More information

Offline IP address to ASN lookup for .NET. Loads an ip2asn TSV dump (IPv4 + IPv6) into a compact in-memory index and resolves an IP to its autonomous system number, country code and AS description with a binary... More information