There are different forms of ISDN, including rate interfaces that allow up to 1.92 Mbps, and ISDN via satellites are used to link to field reporters by the BBC and other broadcasters. Additionally, ISDN's reliability and latency is still yet to be matched by packet switched alternatives.
ISDN is used heavily by the broadcast industry as a reliable way of
switching low latency, high quality, long distance audio circuits. In
conjunction with an appropriate codec using MPEG or various
manufacturers proprietary algorithms, an ISDN BRI can be used to send
stereo bi-directional audio coded at 128 kbit/s with 20 Hz – 20 kHz
audio bandwidth, although commonly the G.722 algorithm is used with a
single 64 kbit/s B channel to send much lower latency mono audio at
the expense of audio quality. Where very high quality audio is
required multiple ISDN BRIs can be used in parallel to provide a
higher bandwidth circuit switched connection. BBC Radio 3 commonly
makes use of three ISDN BRIs to carry 320 kbit/s audio stream for live
outside broadcasts. ISDN BRI services are used to link remote studios,
sports grounds and outside broadcasts into the main broadcast studio.
ISDN via satellite is used by field reporters around the world. It's
also common to use ISDN for the return audio links to remote satellite
In many countries, such as the UK and Australia, ISDN has displaced
the older technology of equalised analogue landlines, with these
circuits being phased out by telecommunications providers. IP based
streaming codecs are starting to gain a foothold in the broadcast
sector, using broadband internet to connect remote studios. However
reliability and latency is crucially important for broadcasters and
the quality of service offered by ISDN has not yet been matched by
packet switched alternatives.