VeriSign operates a diverse array of network infrastructure, including two of the Internet's thirteen root nameservers, the generic top-level domains for .com and .net, one of the largest SS7 signaling networks in North America, and the RFID directory for EPCGlobal. VeriSign also provides a variety of security and telecom services ranging from digital certificates, payments processing, and managed firewalls to mobile call roaming, toll-free call database queries and downloadable digital content for mobile devices. The company groups all of these functions under the banner of 'intelligent infrastructure' services.