ISDN (Integrated Services Digital Network)

A series (I-series) of ITU standards for digital telephone service.
ISDN is usually provided in two variants:

• BRI: Basic Rate Interface - BRI was never very popular but does still exist in North America.
• PRI: Primary Rate Interface - PRI service is widely popular, and is usually delivered over a T1 circuit.

UK

In the UK, BRI is very popular and is known as ISDN2. Signalling can be either PTP (where DDIs are used) or PTMP (MSNs). PRI is delivered over E1 and is known as ISDN30 (irrespective of the number of active channels). Signalling is PTP only.

ISDN Articles

• Cisco.com: ISDN Overview
• Wikipedia ISDN entry
• Hyper Dictionary Article
• DSL

See Also

• EuroISDN
• PRI
• BRI
• ISDN Features
• Sirrix ISDN channels
• Asterisk CAPI Channels mainly for AVM and EICON cards supporting CAPI
• zaptelBRI for inexpensive passive ISDN cards using the HFC chipset and the Quad and OctoBRI cards by Junghanns
• Asterisk ISDN4Linux
• chan_misdn
• Asterisk PRI