AS7011 FRONTIER-AND-CITIZENS

Autonomous System 7011 (FRONTIER-AND-CITIZENS) is one of the networks of

Frontier Communications, a large US telephone and broadband carrier. The

handle preserves the name of Citizens Communications, the utility company

that renamed itself Frontier.

What it's used for

• Consumer and small-business fixed broadband. Reverse DNS across its prefixes is classic subscriber addressing under frontiernet.net — names like static-…dsl1.chi.il.frontiernet.net and …dr01.crvl.il.frontiernet.net.

Notable

• A true eyeball network: the addresses terminate on homes and small offices, not on servers, and the reverse names encode the serving town and state.
• Frontier grew largely by acquiring landline territory from other carriers, so its address space is a patchwork of blocks inherited from predecessor telcos — which is why one company shows up under several ASNs and several rDNS suffixes.