SPECIFICATION of the GENERIC SIGNALLING SYSTEM for INTERCONNECTION Interconnect Specification 4 Page 1 of 12
Index 1 Overview 2 Parts of Signalling No. 7 (UK C7) 2.1 Message Transfer Part 2.2 User Parts 2.2.1 Interconnect User Part 2.2.2 Interconnect User Part with Enveloped ISUP 2.2.3 ETSI ISDN User Part (ETSI ISUP) 2.3 Signalling Connection Control Part 3 Availability 4 Interworking 5 Services 6 Testing 7 References 8 Glossary 9 History Appendix A Signalling Interconnect Options Appendix B Schedules supported by the Signalling Options Page 2 of 12
1. OVERVIEW The ITU-T common channel signalling system number seven (UK C7) shall be used as the signalling system for the conveyance of PSTN and ISDN telephony calls between the Operator and the. At the present time will only offer Interconnect User Part for interconnection as specified in PNO-ISC/Spec/006 (BS PD6645: 2000). However will implement ISDN User Part in due course and the paragraphs on other parts of UK C7 are included for completeness and to show s commitment toward migration. (The various Parts of the signalling are more fully defined in section 2). and the Operator shall support at least one User Part ( in the first instance) and Message Transfer Part (MTP) on each Interconnect Link. The User Parts at each end of the signalling link shall be compatible. The interconnect schematic of s Network using Signalling No.7 (UK C7) is shown in Fig 1. UK Network Env ISUP* SCCP* ETSI ISUP* Local Env ISUP Local Env ISUP Env ISUP Local Network * Not yet available UK National MTP Figure 1 - Signalling No.7 (UK C7) Network Schematic Page 3 of 12
The conveyance of PSTN and ISDN calls between the Operator and the within the UK shall use the national MTP and, unless otherwise available and agreed between the Operator and. For the conveyance of Connectionless Services in support of mobile telephony, the and Operator, may agree to use the SCCP (when available) and MTP. The Operator and shall agree which services and features listed in the schedules to this agreement shall be supported across the interface before shall be obliged to convey UK C7 signalling messages. 2. PARTS OF SIGNALLING SYSTEM No.7 2.1. Message Transfer Part (Mandatory) The and Operator when interconnected in the national signalling domain shall comply with the specification of the SS No.7 Message Transfer Part (MTP) as defined in PNO-ISC/Spec/005 (BS PD6639: 2001). 2.2. User Parts Subject to their availability, the Operator and shall agree to use at least one of the User Parts, defined further in the following sub-sections. The generic availability of these User Parts on the various Types is provided in Section 3. Subject to availability, the Operator and may agree to support a combination of User Parts between their s. The combinations that can be offered on a route by route basis are defined in Appendix A to this specification. 2.2.1 Interconnect User Part (Currently mandatory) The and Operator shall comply with the specification of the UK C7 Interconnect User Part as defined in PNO- ISC/Spec/006 (BS PD6645: 2000), with the following exceptions: a) Where the and Operator support propriety extensions to they shall comply with the PNO-ISC/Info/004 (BS PD6659: 2000), b) If the or Operator does not support a propriety extension to, that shall respond with a connection not admitted message in response to a request for a service not supported. 2.2.2 Interconnect User Part with Enveloped ISUP (Availability to be announced) The and Operator shall comply with the specification of the UK C7 Enveloped ISDN User Part as defined in section 6 of PNO-ISC/Info/004 (BS PD6659: 2000). The and Operator shall use the UK numbering scheme, as used across the interface, for the Page 4 of 12
enveloped ISUP interface. (i.e. the national and international prefixes (0 and 00) shall be conveyed) 2.2.3 European Telecommunications Standards Institute -ISDN User Part (ETSI ISDN-UP or ETSI ISUP) (Availability to be announced) When using ETSI ISUP, within the national MTP, the and Operator shall comply with the specification ETSI ISDN User Part (ETS 300 356-1), with options and modifications to the ITU-T recommendations Q.761 - Q.764 (inclusive), as specified in PNO-ISC/Spec/007 (BS PD6623: 2000). Where the Operator or does not support a particular ISUP message, parameter or value, the ISUP compatibility procedures shall be invoked. i.e. unless otherwise agreed, the Operator and shall use the ISUP compatibility mechanism to ensure that different capabilities in one do not adversely affect the other. For international calls the currently supports solely an ISDN 64kbit/s unrestricted bearer service. Other International ISDN bearer requests shall be routed, and charged, as international telephony calls, providing the correct prefix and/or route is selected. International ISDN 64kbit/s calls shall convey an ISDN prefix digit zero over ETSI ISUP routes, unless otherwise agreed. ISDN speech and ISDN 3.1 khz calls will be treated as telephony calls. 2.3. Signalling Connection Control Part (Availability to be announced) Where the and a UK GSM Mobile Operator have agreed the support of Non Circuit Related Signalling (NCRS) services to enable Global s for Mobile (GSM) telephony users to have GSM Roaming Services when travelling abroad, they shall comply with Connectionless Signalling Protocols of the Signalling Connection Control Part as defined ITU- T recommendations Q.711 - Q.714 (inclusive). 3. AVAILABILITY Type UK National MTP Enveloped ETSI ISDN-UP SCCP* ISUP* (V2)* DLE Yes Yes No No Table 1 UK C7 Signalling Parts available in the. *User Part not yet available from Kingston Communications (Hull) PLC The Parts of the signalling system shall be used between the Operator and the until such time as agreed between the Operator and, or as otherwise lawfully directed by the Director General, Oftel, or the European Union. Page 5 of 12
shall advise the Operator if interconnection of a particular User Part is not available at a specific Point of Interconnection, for example if due to operational constraints. 4. INTERWORKING (WHEN AVAILABLE) The Operator and shall interwork the ETSI ISUP and signalling systems as necessary (e.g. transit calls) in accordance with PNO-ISC/Spec/008 (BS PD6651: 1999), where the conveyance of the service or feature defined is compatible on each of the User Parts. The Operator and shall interwork with enveloped ISUP" with the signalling system as defined in Section 6 of PNO-ISC/Info/004 (BS PD6659: 2000). The number of different versions and implementations of the signalling system makes the delivery of end to end services and features complex. remains responsible for the conveyance of Signalling Messages within the. can have no responsibility or liability for the acts or omissions of any third party telecommunications operator or overseas administration in respect of any signalling message handed over to or received from such third party. cannot guarantee that all services and features that transit the will interwork satisfactorily end to end. and the Operator shall co-operate in accordance with Annex 3 of this Agreement to minimise any service disruption that may arise, for example due to signalling system incompatibilities. 5. SERVICES 5.1 Appendix B to this specification 4 lists the schedules that can be supported and the services and features available on each of the User Parts listed in section 2. Initially some of the services shown may not be supported on the. intends to make these services available as the capability is developed on the 5.2 The services available may vary from those identified in the supplement depending on whether the or the Operator is originating, terminating or transiting, a particular service schedule. 5.3 The Operator and shall inform each other of changes to the interface, services or features according to the terms and conditions defined in this Agreement. 5.4 Subject to paragraphs 5.1 and 5.2 above, the shall support the list of services and/or features identified in a supplement to this Agreement 5.5 Subject to paragraphs 5.1 and 5.2 above, may invoke any of the services or features identified for a particular User Part in Appendix B to this Specification 4. 5.6 Subject to paragraphs 5.1 and 5.2 above, and the Operator shall not invoke services or features not included in Appendix B to this Specification 4, for a particular User Part. Page 6 of 12
6. TESTING The Operator and shall confirm in writing that their implementation conforms to the relevant specifications and identify any deviations from that specification to be agreed between the parties before shall be obliged to convey UK C7 signalling messages. and the Operator agree to test the UK C7 signalling interface in accordance with Annex 2 of this Agreement. The testing shall be completed to both parties satisfaction before shall be obliged to convey UK C7 signalling messages. Where the Operator or enhance the interface by adding a service or feature after interconnection has been provided, the parties shall inform each other, provide details of the changes and agree any additional testing that may be deemed necessary in accordance with the terms and conditions in this Agreement. 7. REFERENCES PNO-ISC/Spec/005 (BS PD6639: 2001) MTP PNO-ISC/Spec/006 (BS PD6645: 2000) PNO-ISC/Spec/007 (BS PD6623: 2000) ISDN User Part PNO-ISC/Spec/008 (BS PD6651: 1999) - ISUP Interworking PNO-ISC/Info/004 (BS PD6659: 2000) Proprietary Extensions to PNO-ISC/ADM/063 PNO-ISC Administration Document 063 ITU-T Q.711 Functional description of the signalling connection control part ITU-T Q.712 Definition and function of SCCP messages ITU-T Q.713 SCCP format and codes ITU-T Q.714 Signalling connection control part procedures ITU-T Q.761 Functional description of the ISDN user part of signalling system No. 7 ITU-T Q.762 General function of messages and signals ITU-T Q.763 Formats and codes ITU-T Q.764 Signalling procedures 8. GLOSSARY ETSI GSM IAM ISDN ISUP ITU-T MTP NCRS Oftel PNO PNO-ISC PSTN SCCP TUP European Telecommunications Standards Institute Global for Mobile Initial Address Message (Part of UK C7 message set) Integrated Services Digital Network ISDN User Part International Telecommunications Union - Telecommunications Interconnect User Part Kingston Communications (Hull) PLC Message Transfer Part Non Circuit Related Switching Office of Telecommunications Public Network Operator Public Network Operators - Interconnect Standards Committee Public Switched Telephony Network Signalling Connection Control Part Telephony User Part Page 7 of 12
9. HISTORY Issue 1 April 1998 Issue 1.1 April 2002 (Not published) Issue 1.2 July 2002 END OF SPECIFICATION Kingston Communications (Hull) Plc Regulatory Affairs and Technology Development Group Carr Lane, Kingston Upon Hull HU1 3RE Page 8 of 12
APPENDIX A - SIGNALLING INTERCONNECT OPTIONS Option Available on the National MTP 1 Signalling Route Operator Traffic Route 2 with Enveloped ISUP Signalling Route* Operator with Enveloped ISUP Traffic Route* Operator 3 ETSI (UK) ISUP Signalling Route * ETSI (UK) ISUP Traffic Route* Operator 4 Shared / ETSI (UK) ISUP Signalling Route* Traffic Route* ETSI (UK) ISUP Traffic Route* Operator 5 Signalling Route Traffic Route ETSI (UK) ISUP Signalling Route* ETSI (UK) ISUP Traffic Route* Operator 6. SCCP Signalling Route* Plus Either Option 1,3 or 4 7. Shared SCCP included on a Signalling Route of Options 1,3 or 4* * These options not currently available Page 9 of 12
APPENDIX B - SCHEDULES SUPPORTED by the SIGNALLING OPTIONS Table 1 shows which Schedules are supported by the Signalling Options identified in the Specification of the Generic Signalling for Interconnection: (I/C Specification 4). Notes to Tables. Service or facility provided across the signalling interface by the Service or facility not provided across the signalling interface by the TABLE 1 1 SCHEDULE 2 with Env ISUP 3 ETSI ISUP 4 SCCP 2 Telephony Calls to the See Table 2 for details 3 Indirect Access Calls 5 Speaking Clock Service 5 5 6 National Operator Assistance Service 5 5 7 Directory Enquiry Service See Table 3 8 Branded Directory Enquiry Service See Table 3 9 Emergency Service See Table 3 10 0820 Calls 11 Reciprocal Number Portability 5 12 Reciprocal Ring Back When Free Service 6 7 13 Number Free Service Calls 5 5 5 14 Low-Call Service Calls 15 Premium Rate Service Calls 16 National Rate Service Calls 5 5 5 17 Access Calls to the Operator Chargecard 18 International Outgoing Calls to See Table 2 for details authorised Overseas s via the Operator 19 International Incoming Calls from See Table 2 for details authorised Overseas s via the Operator 21 Operator - Operator Service See Table 3 102 Operator Telephony Calls to the Operator See Table 2 107 Access Calls to the Chargecard 110 Operator 0820 Calls 6 1 These tables primarily indicate the super-set of services and signalling features which can be conveyed by the signalling User Parts on s national MTP. Where more than one Schedule is being employed to support an end to end service an appropriate signalling option will need to be used on the interconnect route(s) used. Currently only services using are supported. 2 Information based on PNO-ISC/ADM/063 3 The telephony, and ISDN services offered on s network terminations will be formed from this super-set of schedules and features. 4 UK Variant to PNO-ISC/Spec/007 (BS PD6623: 2000). 5 National Calls only 6 Available from telephony, Euro-compatible and non-euro specified ISDN customer equipment 7 Available to analogue customers on compatible exchanges only Page 10 of 12
113 Operator Free Phone Service Calls 114 Operator Local Fee Service Calls 115 Operator Premium Rate Service Calls 116 Operator National Rate Service Calls 117 Operator Personal Number Service Calls 5 5 5 Table 2 shows the ISDN Services and Features supported by the available interconnect Signalling Options. The table provides the super-set of the signalling features which can be supported by the network signalling system. and other network operators may develop retail customer service offerings which employ these network signalling options. Due to the options and variations within the customers Local Access Signalling s as implemented by manufacturers of Customer Premises Equipment (CPE) and by various network switch manufacturers, the end to-end functionality of the ISDN services cannot be guaranteed. TABLE 2 1 Service / Feature Enveloped ISUP ETSI ISUP 8 Basic Call, Speech 8 9 9 Basic Call, 64 kbit/s 9 8 Basic Call, 3.1 khz 10 11 11 7 khz Audio (without Fallback) 7 khz Audio (with fallback) Telephony, 8 10 Videotelephony (without Fallback) Videotelephony (with fallback) Telefax Group 2/3 Telefax Group 4 Teletex Videotex Eurofile 11 FTAM over ISDN 12 Alternate Speech/ 64 kbit/s (SWAP) 12 Calling Line Identification Presentation CLIP 14 8 Calling Line Identification Restriction CLIR 6 Connected Line Identification Presentation (COLP) 14 Connected Line Identification Restriction (COLR) 15 Calling Number Display Terminal Portability Sub-addressing 15 16 Malicious Call Identification with Hold 17 17 14 8 8 In the Superset of ISDN service/feature available via the Operator from Authorised Overseas s 9 International ISDN speech calls will be treated as international telephony calls 10 Supported by TUP & ESTI & ITUT ISUP on the International MTP 11 International ISDN 3.1 khz calls will be treated as international telephony calls 12 Not available to analogue or non-euro compatible ISDN customers 13 Not available to Euro -ISDN customers 14 Supported by ESTI & ITU-T on the international MTP 15 Only available between Euro-ISDN customers 16 6 Octet sub-address only Page 11 of 12
DASS/ETSI Presentation Number 18 19 Call Forwarding Unconditional 19 Call Forwarding on Busy 20 Call Forwarding on No Reply 20 Ability to convey Network Provided CLI and presentation Number in the same call / IAM Table 3 shows the ISDN Operator Administrative Features supported by the available interconnect Signalling Options which are provided across the signalling interface by the. OPERATOR ADMIN. FEATURES (Speech Calls) TABLE 3 1 Envelope d ETSI ISUP ISUP Customer Identification Information Emergency Service Interception (SVI) Changed Number Interception (CNI) Admin. Hold Trace Operator Override (OOR) Directory Enquiries 17 20 Octect sub-address between Euro-ISDN customers. Only 6 Octets may be available if call involves a non-euro-compatible ISDN network termination. 18 MCI may be supported "without hold" where a call originates from a network which supports first party release protocols (i.e Mobile networks). ETSI ISUP supports MCI "without hold". 19 Capability to exchange Presentation Numbers between ISDN customers. This does not include interworking with analogue customers. 20 Supported for Speech Calls Only (using Call Divert protocols) Page 12 of 12