IDSL

ISDN Digital Subscriber Line (IDSL) transmits data digitally across existing ISDN lines, at a rate of 128 kbit/s. The benefits of IDSL over ISDN are that IDSL provides always-on connections and transmits data via a data network rather than the Carriers voice network

IDSL also avoids per-call fees by being generally billed at a flat-rate.

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