Abstract: A communication system (500) includes a plurality of subscriber systems (510) coupled to a plurality of twisted pair data lines (520). Each subscriber system (510) has an availability guarantee value, which may specify a level of service for the subscriber system (510). A communication server (502) is coupled to the plurality of subscriber systems (510). The communication server (502) selectively couples a subscriber system (510), responsive to a request for service, to either a first modem pool (530) or a second modem pool (540) based on the availability guarantee value associated with the subscriber system (510). Communication server (502) can also provide a soft-termination state and dynamic network address allocation for subscriber systems (510).