The HCH network is provided through the current FTS2000 service by AT&T and features a dry-line service (no voltage on the line), unlike a standard home telephone service that has a constant voltage to each drop on the line. The HCH phone set (manufactured by Communications Laboratories, Owls Head, ME) provides all necessary interface requirements for accessing the network. Instead of the standard switching required by home telephones, the network uses a set of bridges to maintain a minimum level of signal. This allows any user on the network to monitor discussions of other users via the HCH phone internal speaker without being directly called. If for any reason the local phone system becomes unusable (e.g., too many calls, power outages, etc.), this feature also provides assurance that the HCH network will still operate in a congested and catastrophic telecommunications environment.