Referring to capacity available through a network as required by an application, perhaps during the course of a call. Asynchronous transfer mode (ATM) offers guaranteed bandwidth-on-demand, at least theoretically, adjusting the amount of bandwidth required to support a call once the call is established and guaranteeing that it will be available when required. As an example, real-time compressed voice over ATM may require no bandwidth during periods of prolonged silence, but requires guaranteed bandwidth at precise intervals during periods of speech activity. Frame relay offers bandwidthon-demand within the limits of the committed information rate (CIR), on average, and within the limits of the port speed, as resources are available. ISDN and some other network services also offer bandwidthon-demand, defined in various ways. See also ATM, bandwidth, call, CIR, compression, frame relay, ISDN, port, and real-time.