SIST ETS 300 201/A1 E1:2003

• Abstract:

  Amendment to the current text regarding the interaction with CW.

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.080 - Integrated Services Digital Network (ISDN)
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Ref Project: ETSI ETS 300 201/A1 ed.1 (1996-09) - Integrated Services Digital Network (ISDN); Call Forwarding No Reply (CFNR) supplementary service; Service description

SIST ETS 300 201/A1 E1:2003 is a Slovenian standard published by SIST and identical to ETS 300 201/A1 Edition 1. It is an amendment to the Integrated Services Digital Network (ISDN) Call Forwarding No Reply (CFNR) supplementary service description, focused on how CFNR interacts with call waiting (CW). It is aimed at telecom engineers, service designers, operators, and testers who need to implement or verify that behavior.

What does SIST ETS 300 201/A1 E1:2003 specify?

SIST ETS 300 201/A1 E1:2003 revises ETS 300 201 (1994) to clarify the CFNR/CW interaction. In practice, it tells implementers how to handle a waiting call, forwarding, and notification when an unanswered call is diverted.

Part	What it covers
Foreword	States the purpose of the amendment and records the transposition milestones
Clause 7	Adds a note about when call waiting notification to the calling user may still be seen
Subclause 8.2	Adds the rules for waiting calls, CFNR timer expiry, forwarding notification, multiple diversions, and forwarded calls
History	Records the approval and publication history

What are the key requirements of SIST ETS 300 201/A1 E1:2003?

SIST ETS 300 201/A1 E1:2003 adds a small set of service rules, but they matter because they determine what users actually experience when CFNR and CW are both active.

• Clause 7 says that an ISDN user’s wish not to send a call waiting notification to the calling user cannot always be met. In practice, a network or terminal may still deliver a notification path, for example voice notification, when the calling user is outside the called user’s ISDN.

• Subclause 8.2 says that if user B has activated CFNR, a waiting call shall still be offered. That means CFNR does not prevent the initial call waiting presentation.

• Subclause 8.2 also says that if the CFNR timer expires before an answer is received, CFNR shall be invoked, the call shall be forwarded, and call waiting shall cease. In practice, the switch must keep timing the unanswered call and change to forwarding when the timer runs out.

• Subclause 8.2 links forwarding notification to the subscription option “Calling user receives notification that the call has been forwarded”. If the forwarding user selects No, no call waiting notification shall be sent to the calling user from the forwarded-to user.

• Subclause 8.2 adds a rule for multiple diversions: call waiting notification shall be sent to the calling user only if all diverting users allow notification that the call has been forwarded. This matters for chained forwarding, where one user’s setting can block the notification.

• Subclause 8.2 says that a forwarded call can invoke the call waiting supplementary service. In practice, the forwarded-to destination may still treat the incoming forwarded call like any other call for CW purposes.

What terms does SIST ETS 300 201/A1 E1:2003 define?

• Integrated Services Digital Network (ISDN) - The digital network environment in which CFNR and CW operate.

• Call Forwarding No Reply (CFNR) - The supplementary service that forwards an unanswered call after the CFNR timer expires.

• Call Waiting (CW) - The supplementary service that alerts a user to another incoming call while the user is already engaged.

• calling user - The party placing the original call and receiving any notification related to forwarding.

• forwarding user - The user whose subscription controls forwarding behavior and related notification options.

• forwarded-to user - The destination user who receives the forwarded call and may still trigger CW.

• user B - The called user in the service-interaction rules, the party whose CFNR activation is being considered.

Who uses SIST ETS 300 201/A1 E1:2003?

SIST ETS 300 201/A1 E1:2003 is used by ISDN network operators, switch vendors, terminal equipment designers, and telecom test teams. It is also relevant to service managers and buyers who need to specify or check forwarding and call waiting behavior in ISDN equipment and services.

What changed in SIST ETS 300 201/A1 E1:2003 from the previous edition?

SIST ETS 300 201/A1 E1:2003 is Amendment 1 to ETS 300 201 (1994). The amendment states that it:

• clarifies the interaction between CFNR and CW,
• adds a note in clause 7 on cases where call waiting notification to the calling user may still occur,
• inserts new text in subclause 8.2 about offering a waiting call when CFNR is active,
• defines what happens when the CFNR timer expires,
• ties forwarding notification settings to notification sent to the calling user,
• covers multiple diversions, and
• states that a forwarded call can invoke CW.

Which standards are used with SIST ETS 300 201/A1 E1:2003?

SIST ETS 300 201/A1 E1:2003 is used with ETS 300 201 (1994), the base CFNR service description that this amendment modifies. The amendment updates that underlying text rather than replacing it.

What does the SIST ETS 300 201/A1 E1:2003 document contain?

• A foreword that explains the purpose of the amendment and records its adoption and publication milestones.
• Amendment text for clause 7, focused on call waiting notification toward the calling user.
• Amendment text for subclause 8.2, focused on CFNR timer expiry, forwarding, notification settings, multiple diversions, and CW after forwarding.
• A history section that records the document lineage from the first edition through Amendment 1.

SLOVENSKI STANDARD
01-december-2003
Digitalno omrežje z integriranimi storitvami (ISDN) – Dopolnilna storitev: podaja
klica, ko ni odziva (CFNR) – Opis storitve
Integrated Services Digital Network (ISDN); Call Forwarding No Reply (CFNR)
supplementary service; Service description
Ta slovenski standard je istoveten z: ETS 300 201/A1 Edition 1
ICS:
33.080 Digitalno omrežje z Integrated Services Digital
integriranimi storitvami Network (ISDN)
(ISDN)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

ETS 300 201
AMENDMENT A1
September 1996
Source: ETSI TC-NA Reference: RE/NA-010045
ICS: 33.020
Key words: ISDN, CFNR, supplementary service
This amendment A1 modifies
the European Telecommunication Standard ETS 300 201 (1994)
Integrated Services Digital Network (ISDN);
Call Forwarding No Reply (CFNR) supplementary service;
Service description
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
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Tel.: [phone] - Fax: [phone]
Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and the
foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 1996. All rights reserved.

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ETS 300 201: December 1994/A1: September 1996
Whilst every care has been taken in the preparation and publication of this document, errors in content,
typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to
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ETS 300 201: December 1994/A1: September 1996
Foreword
This amendment to ETS 300 201 (1994) has been produced by the Network Aspe
...