AS11776 ATLANTICBB-JOHNSTOWN

ATLANTICBB-JOHNSTOWN is Breezeline, the cable broadband operator formerly known as Atlantic Broadband. The handle still names Johnstown, Pennsylvania, but the network this AS carries reaches well beyond it. This is a consumer eyeball network — the largest in this AS range by a wide margin.

What it's used for

Residential and small-business broadband access. RIS sees 1,901 IPv4 prefixes carrying just over 1,050,000 addresses, 19 IPv6 prefixes, and 32 observed BGP neighbours. That ratio is the definitive eyeball signature: a million addresses behind only a few dozen peers means the space terminates at customers, not at other networks. A carrier of the same address size would peer with hundreds. The reverse DNS removes any doubt — sampled hosts answer as d-75-118-0-5.oh.cpe.breezeline.net and static-23-244-0-5.oh.cpe.breezeline.net. cpe is customer-premises equipment: cable modems in homes.

Notable

The rDNS doubles as a service map. State codes are embedded in the names — oh for Ohio, nh for New Hampshire, sc for South Carolina, fl for Florida — across three surviving domains: breezeline.net, atlanticbb.net and metrocast.net. The prefix registrants match: blocks register variously to Breezeline, Atlantic Broadband and Metrocast Cablevision. Those are not unrelated third parties but the same company under successive names, Metrocast having been absorbed into Atlantic Broadband before the Breezeline rebrand.

Interesting

Nearly 1,900 prefixes for one million addresses works out to an average block smaller than a /22. Cable operators accumulate address space in small fragments, market by market, and rarely get to aggregate it afterwards.