InCyb ISDN Page
Industrial Cyberspace (InCyb)
was the first company sponsor member of the Texas ISDN Users' Group and
is a charter member of that organization.
James Lee "JJ" Johnson, Internet
Software Engineer, is a technical editor and contributor to Special Edition,
Using ISDN, published by QUE and written by James Y. Bryce.
What is ISDN?
ISDN, Integrated Services Digital Network
- ISDN is a digital telephone service.
- ISDN has higher data speed and better data integrity than
standard analog telephone service.
- ISDN dials and connects much faster than standard analog
- B channels are used for voice or data.
- D channels are used for call control, signaling, or X.25
- NI-1, National ISDN 1, is the standard ISDN service being
deployed in Texas and much of the U.S.
BRI, Basic Rate Service (2B+D)
- 2 B channels, 64 Kbps each
- 1 D channel, 16 Kbps
- ISDN BRI is brought to your home or business over a
twisted pair of copper wires, just like a standard analog
PRI, Primary Rate Interface (23B+D)
- 23 B channels, 64 Kbps each
- 1 D channel, 64 Kbps
- ISDN PRI is brought to your site via the same physical
media as a T1 line (U.S.).
Copyright 1995, 1996, 1997, 1998, 1999 by Industrial
Cyberspace, Austin, Texas.