IMG 1010 - Overview of ISDN

Owned by Kelli Higdon
Last updated: Mar 04, 2024
2 min read

Overview of ISDN

The IMG supports (ISDN) Integrated Services Digital Network for a complete digital telephone/telecommunications network which will carry voice, data, and video over an existing telephone network. The IMG supports 128 Kbps high-speed and high-bandwidth service. ISDN non-compressed (512 Kbps compressed) can also provide on-demand service and can connect up to eight devices simultaneously with each device being call-managed.

  • IMG 1010/1004- The basic configuration is 23B+D (Primary Rate Interface) and 30B+D outside of North America.

  • IMG 1010/1004- Interfaces to various equipment types supporting the ISDN PRI protocol including tandem (Class 4) switches and end office (Class 5) switches.

  • IMG 1010/1004- The IMG ISDN PRI implementation is based on ITU-T Q.921 and Q.931 specifications. Each implemented variant references the appropriate interface document supplied by the equipment manufacturer. The interface document is usually a variant of the ITU-T recommendations.

  • IMG 1010/1004- Supports up to 32 D channels. Each D channel provides the High Data Link Control (HDLC) communications over T1, E1, or DS3 on one timeslot on the span.

  • IMG 1010- (NFAS) Each D channel on the IMG 1010 can control up to 19 other spans in addition to the span on which it is located.

  • IMG 1004- (NFAS) Each D channel on the IMG 1004 can control up to 3 other spans in addition to the span on which it is located.

  • IMG 1010/1004- Supports sending UUI (User to User Information) between called and calling parties during the Setup, Clearing, and Active Phase of the Call. The User to User Information support passes specific information not pertaining to the call from one user to another.

Notes regarding ISDN PRI NI2:

IMG 1010:

The IMG supports one D channel per span [Facility Associated Signaling (FAS)], or one D channel managing up to 20 spans [Non-Facility Associated Signaling (NFAS)].

IMG 1004:

The IMG supports one D channel per span [Facility Associated Signaling (FAS)], or one D channel managing up to 4 spans [Non-Facility Associated Signaling (NFAS)].

 

Connection endpoint variants are defined for National ISDN as User side and Network side. You can intermix both FAS and NFAS D channels with each supporting a different variant. See IMG 1010 - Configuring ISDN Signaling for more information

 

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