# Supplementary services and ISDN variants

ISDN supplementary services are implemented differently under various variants. NMS ISDN supports a subset of supplementary services in the following variants:

- The Digital Signaling System No. One (DSS1) European Telecommunications Standard (ETS) produced by the Signaling Protocols and Switching (SPS) Technical Committee of the European Telecommunications Standards Institute (ETSI). In this document, this variant is referred to as the ETS 300 variant.

- The Q.SIG signaling system for corporate networking. Q.SIG is standardized by a consortium of standards-producing bodies, including ETSI, the European Computer Manufacturer's Association (ECMA), and the International Organization for Standardization (ISO). The production effort is coordinated by the IPNS Forum. In this document, this variant is referred to as the Q.SIG variant.

- The National ISDN Protocol specified by Telcordia (previously Bellcore). The National ISDN protocol was developed to be a common, vendor neutral protocol for North America that would enhance interoperability of equipment by replacing several proprietary vendor protocols. In this document, this variant is referred to as the National ISDN 2 (NI2) variant.

- The ISDN Primary Rate User-Network Interface Specification by Nortel Networks. In this document, this variant is referred to as the DMS variant.

For other variant specification information, refer to the Dialogic® NaturalAccess™ ISDN Software Installation Manual.

## ETS 300 variant specifications

The NMS ETS 300 variant implementation is a reference to the Digital Subscriber Signaling System No. One (DSS1) European Telecommunications Standard (ETS) produced by the Signaling Protocols and Switching (SPS) Technical Committee of the European Telecommunications Standards Institute (ETSI). The standard can be categorized as a basic Q.931 protocol with the addition of ASN.1 facilities to support ISDN supplementary services.

The following documents describe supplementary services as they are implemented in the NMS ETSI supplementary service package:

- ETS 300 102-1 (1990): "Integrated Services Digital Network (ISDN) User-network interface layer 3; Specifications for basic call control."

- ETS 300 195-1: "Integrated Services Digital Network (ISDN); Supplementary service interactions; Digital Subscriber Signaling System No. One (DSS1) protocol; Part 1: Protocol specification."

- ETS 300 196-1 (1993): "Integrated Services Digital Network (ISDN); Generic functional protocol for the support of supplementary services; Digital Subscriber Signaling System No. One (DSS1) protocol; Part 1: Protocol Specification."

- ETS 300 207-1 (1994): "Integrated Services Digital Network (ISDN); Diversion supplementary services; Digital Subscriber Signaling System No. One (DSS1) protocol; Part 1: Protocol Specification."

## Q.SIG variant specifications

Q.SIG specifications are produced by a consortium of standards-producing bodies, including ETSI, the European Computer Manufacturer's Association (ECMA), and the International Organization for Standardization (ISO). The production effort is coordinated by the IPNS Forum.

The NMS ISDN Q.SIG implementation is based on ETSI second-edition specifications. These were produced after ECMA-created standards (based on CCITT standards and enhanced by ECMA after a European Commission mandate to produce such standards) were submitted to the ISO/IEC.

The following table contains a partial list of standards documents that are relevant to the NMS ISDN implementation. Where two standards are listed, the first is the stage 1/stage 2 standard and the second is the stage 3 (Q.SIG) standard.

Q.SIG service name | ECMA standard and publication date | ETSI standard and publication date | ISO/IEC standard and publication date
--- | --- | --- | ---
Basic call (64 kb/s unrestricted, 3.1 kHz audio and speech bearer services) | ECMA-142/143, December 2001 | ETS300 171/172, June 2003 | IS 11574/11572, 2000
Calling name identification presentation | ECMA 163/164, December 2001 | ETS300 237/238, June 2003 | IS 13864/13868, 1995
Connected name identification presentation | ECMA 163/164, December 2001 | ETS300 237/238, June 2003 | IS 13864/13868, 1995
Calling/connected name identification restriction | ECMA 163/164, March 1992 | ETS300 237/238, June 1993 | IS 13864/13868, 1995
Generic functional procedures | ECMA 165, June 2001 | ETS300 239, June 2003 | IS 11582, 2002
Call forwarding unconditional | ECMA 173/174, June 1992 | ETS300 256/257, November 1993 | IS 13872/13873 1995
Call forwarding busy | ECMA 173/174, June 1992 | ETS300 256/257, November 1993 | IS 13872/13873, 1995
Call forwarding no reply | ECMA 173/174, June 1992 | ETS300 256/257, November 1993 | IS 13872/13873, 1995
Call transfer | ECMA 177/178, December 2001 | ETS300 260/261, August 2003 | IS 13865/13869, 2003
Advice of charge, start of call | ECMA 211/212, December 1994 |  |
Advice of charge, during call | ECMA 211/212, December 1994 |  |
Advice of charge, end of call | ECMA 211/212, December 1994 |  |
Calling line identification presentation | ECMA-148, June 1997 | ETS300 173, May 1996. There is no stage 3 standard for this supplementary service and Q.SIG support is covered by the basic call stage 3 standard. | IS 14136, 1995. There is no stage 3 standard for this supplementary service and Q.SIG support is covered by the basic call stage 3 standard.
Connection line identification presentation | ECMA-148, June 1990. There is no stage 3 standard for this supplementary service and Q.SIG support is covered by the basic call stage 3 standard. | ETS300 173, December 1992. There is no stage 3 standard for this supplementary service and Q.SIG support is covered by the basic call stage 3 standard. | IS 14136, 1995. There is no stage 3 standard for this supplementary service and Q.SIG support is covered by the basic call stage 3 standard.
Calling/connected line identification restriction | ECMA-148, June 1990. There is no stage 3 standard for this supplementary service and Q.SIG support is covered by the basic call stage 3 standard. | ETS300 173, December 1992. There is no stage 3 standard for this supplementary service. and Q.SIG is covered by the basic call stage 3 standard. | IS 14136, 1995. There is no stage 3 standard for this supplementary service and Q.SIG support is covered by the basic call stage 3 standard.

### Q.SIG specifications

In the ISO specifications, Q.SIG is referred to as Private Signaling System No. One. The Q.SIG specifications identify different types of private ISDN network exchanges (PINXs) and different supplementary services. This creates a conformance matrix.

### Q reference points

The Q reference point is different from typical reference points in that it describes the functions of a part of the network, rather than describing a point of interface to the network. The reference point location also implies that there is no user or network side of a connection. Rather, all Q.SIG signaling is symmetric between adjacent nodes.

## NI2 variant

The NMS NI2 variant implementation is a reference to the National ISDN Protocol specified by Telcordia. The standard can be categorized as a basic Q.931 protocol with the addition of ASN.1 facilities to support NMS ISDN supplementary services.

The GR-2865-CORE, Issue2 (1997): "Two B Channel Transfer (TBCT) Bellcore Generic Requirements" document describes supplementary services as they are implemented in the NMS NI2 supplementary service package.

## DMS variant

The NMS DMS variant implementation is based on the ISDN primary rate interface (PRI) user-network interface specification of Nortel Networks. The specification defines the interface between the Nortel Networks ISDN DMS-100 switch and user equipment.