ITU-T E-Series Recommendations

(last updated: 2-Nov-2000 13:50)

E Series: Overall Network Operation, Telephone Service, Service Operation


  1. E.100 (11/88)
    Definitions of terms used in international telephone operation.

General Provisions Concerning Administrations

  1. E.104 (02/95)
    International telephone directory assistance service sand public access.
  2. E.105 (08/92)
    International telephone service.
  3. E.106 (03/00)
    Description of an International Emergency Preference Scheme (IEPS).
  4. E.109 (02/95)
    International billed number screening procedures for collect and third-party calling.
  5. E.110 (11/88)
    Organization of the international telephone network.
  6. E.111 (11/88)
    Extension of international telephone services.
  7. E.112 (11/88)
    Arrangements to be made for controlling the telephone services between two countries.
  8. E.113 (05/97)
    Validation procedures for the international telecommunications charge card service.
  9. E.114 (11/88)
    Supply of lists of subscribers (directories and other means).
  10. E.115 (02/95)
    Computerized directory assistance.
  11. E.116 (05/97)
    International telecommunication charge card service.
  12. E.117 (06/94)
    Terminal devices used in connection with the public telephone service (other than telephones).
  13. E.118 (07/96)
    The international telecommunication charge card.

General Provisions Concerning Users

  1. E.120 (11/88)
    Instructions for users of the international telephone service.
  2. E.121 (07/96)
    Pictograms, symbols and icons to assist users of the telephone service.
  3. E.122 (11/88)
    Measures to reduce customer difficulties in the international telephone service.
  4. E.123 (11/88)
    Notation for national and international telephone numbers.
  5. E.124 (11/88)
    Discouragement of frivolous international calling to unassigned or vacant numbers answered by recorded announcements without charge.
  6. E.125 (10/84)
    Inquiries among users of the international telephone service.
  7. E.126 (11/88)
    Harmonization of the general information pages of the telephone directories published by administrations.
  8. E.127 (11/88)
    Pages in the telephone directory intended for foreign visitors.
  9. E.128 (11/88)
    Leaflet to be distributed to foreign visitors.
  10. E.130 (11/88)
    Choice of the most useful and desirable supplementary telephone services.
  11. E.131 (11/88)
    Subscriber control procedures for supplementary telephone services.
  12. E.132 (11/88)
    Standardization of elements of control procedures for supplementary telephone services.
  13. E.133 (11/88)
    Operating procedures for cardphones.
  14. E.134 (03/93)
    Human factors aspects of public terminals: generic operating procedures.
  15. E.135 (10/95)
    Human factors aspects of public telecommunication terminals for people with disabilities.
  16. E.136 (05/97)
    Specification of a tactile identifier for use with telecommunication cards.
  17. E.137 (05/97)
    Specification of a tactile identifier for use with telecommunication cards.

Operation of International Telephone Services

  1. E.140 (08/92)
    Operator-assisted telephone service.
  2. E.141 (03/93)
    Instructions for operators on the operator assisted international telephone service.
  3. E.148 (11/88)
    Routing of traffic by automatic transit exchanges.
  4. E.149 (11/88)
    Presentation of routing data.
  5. E.151 (08/92)
    Telephone conference calls.
  6. E.152 (07/96)
    International freephone service.
  7. E.153 (10/96)
    Home country direct.
  8. E.154 (03/98)
    International Shared Cost Service.
  9. E.155 (03/98)
    Internatioal Premium Rate Service.

Numbering Plan of the International Telephone Service

  1. E.160 (1993)
    Definitions relating to national and international numbering plans.
  2. E.161 (05/95)
    Arrangement of digits, letters and symbols on telephones and other devices that can be used for gaining access to a telephone network.
  3. E.162 (04/95)
    Capability for seven digit analysis of international E.164 numbers at time T.
  4. E.164 (05/97) (same as I.331) + Supp 1 (03/98) + Supp 2 (11/98)
    The International Public Telecommunication Numbering Plan.
  5. E.164.1 (03/98)
    Criteria and Procedures for the Reservation, Assignment and Reclamation of E.164 Country Codes and Associated Identification Codes (ICs).
  6. E.165 (11/88) (same as Q.11 ter)
    Timetable for coordinated implementation of the full capability of the numbering plan for the ISDN era (Recommendation E.164).
  7. E.165.1 (10/96)
    Use of escape code "0" within the E.164 numbering plan during the transition period to implementation of NPI mechanism.
  8. E.166 (03/98) (same as X.122)
    Numbering plan interworking for the E.164 and X.121 numbering plans.
  9. E.167 (11/88)
    ISDN network identification codes.
  10. E.168 (05/99)
    Application of E.164 numbering plan for UPT.
  11. E.169 (11/98)
    Application of E.164 numbering plan for universal international freephone numbers for international freephone service.
  12. E.169.2 (10/00)
    Application of Recommendation E.164 Numbering Plan for Universal International Premium Rate Numbers for the International Premium Rate Service.
  13. E.169.3 (10/00)
    Application of Recommendation E.164 Numbering Plan for Universal International Shared Cost Numbers for the International Shared Cost Service.

International Routing Plan

  1. E.170 (10/92)
    Traffic routing.
  2. E.171 (11/88)
    International telephone routing plan.
  3. E.172 (10/92)
    ISDN routing plan.
  4. E.173 (08/91)
    Routing plan for interconnection between public land mobile networks and fixed terminal networks.
  5. E.174 (04/95)
    Routing principles and guidance for Universal Personal Telecommunications (UPT).
  6. E.175 (11/88)
    Models for international network planning.
  7. E.177 (10/96)
    B-ISDN routing.

Tones in National Signalling Systems

  1. E.180 (03/98) (same as Q.35) + Supp 2 (01/94)
    Technical characteristics of tones for the telephone service.
  2. E.181 (11/88)
    Customer recognition of foreign tones.
  3. E.182 (03/98)
    Application of tones and recorded announcements in telephone services.
  4. E.183 (03/98)
    Guiding principles for telephone announcements.
  5. E.184 (11/88)
    Indications to users of ISDN terminals.
  6. E.190 (05/97)
    Principles and Responsibilities for the Management, Assignment and Reclamation of E-Series International Numbering Resources.
  7. E.191 (03/00)
    B-ISDN numbering and addressing.
  8. E.193 (03/00)
    E.164 Country Code Expansion.
  9. E.195 (10/00)
    ITU-T International Numbering Resource Administration.

Maritime Mobile Service and Public Land Mobile Service

  1. E.200 (1988)
    Operational provisions for the maritime mobile service.
  2. E.201 (08/91)
    Reference recommendation for mobile services.
  3. E.202 (10/92)
    Network operational principles for future public mobile systems and services.
  4. E.210 (11/88) (same as F.120)
    Ship station identification for VHF/UHF and maritime mobile-satellite services.
  5. E.211 (11/88)
    Selection procedures for VHF/UHF maritime mobile services.
  6. E.212 (11/98)
    Identification plan for land mobile stations.
  7. E.213 (11/88)
    Telephone and ISDN numbering plan for land mobile stations in public land mobile networks (PLMN).
  8. E.214 (11/88)
    Structure of the land mobile global title for the signalling connection control part (SCCP).
  9. E.215 (05/97)
    Telephone/ISDN numbering plan for the mobile-satellite services of INMARSAT.
  10. E.216 (1993)
    Selection procedures for the INMARSAT mobile-satellite telephone and ISDN services.
  11. E.220 (02/96)
    Interconnection of public land mobile networks (PLMN).

Charging in the International Telephone Service

  1. E.230 (08/92)
    Chargeable duration of calls.
  2. E.231 (06/92) (same as D.103)
    Charging in automatic service for calls terminating on a recorded announcement stating the reason for the call not being completed.
  3. E.232 (11/88) (same as D.104)
    Charging for calls to subscriber's station connected either to the absent subscriber's service or to a device substituting a subscriber in his absence.

Procedures for Remuneration of Administrations for Facilities Made Available

  1. E.250 (10/92) (same as D.150)
    New system for accounting in international telephony.
  2. E.251 (12/72) (same as D.151)
    Old system for accounting in international telephony.
  3. E.252 (11/88) (same as D.160)
    Mode of application of the flat-rate price procedure set forth in Recommendations D.67 and D.150 for remuneration of facilities made available to the Administrations of other countries.

Measuring and Recording Call Durations for Accounting Purposes

  1. E.260 (11/88)
    Basic technical problems concerning the measurement and recording of call durations.
  2. E.261 (11/88)
    Devices for measuring and recording call durations.

Establishment and Exchange of International Accounts

  1. E.270 (03/95) (same as D.170)
    Monthly telephone and telex accounts.
  2. E.275 (09/95) (same as D.190)
    Exchange of international traffic accounting data between Administrations using electronic data interchange (EDI) techniques.
  3. E.276 (06/92) (same as D.176)
    Transmission in encoded form of telephone reversed charge billing and accounting information.
  4. E.277 (12/72) (same as D.174)
    Conventional transmission of information necessary for the collection of charges and the accounting regarding collect and credit card calls.

Utilization of the International Telephone Network for Non-Telephony

  1. E.300 (11/88)
    Special uses of circuits normally employed for automatic telephone traffic.
  2. E.301 (03/93)
    Impact of non-voice applications on the telephone network.


  1. E.320 (11/88)
    Speeding up the establishment and clearing of phototelegraph calls.
  2. E.323 (11/88) (same as F.82) (same as F.107)
    Rules for phototelegraph communications set up over circuits normally used for telephone traffic.

ISDN Provisions Concerning Users

  1. E.330 (11/88)
    User control of ISDN-supported services.
  2. E.331 (10/91)
    Minimum user-terminal interface for a human user entering address information into an ISDN terminal.
  3. E.333 (11/88) (same as Z.323)
    Man-machine interaction.
  4. E.350 (03/00)
    Dynamic Routing Interworking.
  5. E.351 (03/00)
    Routing of Multimedia Connections Across TDM-, ATM-, and IP-Based Networks.
  6. E.352 (03/00)
    Routing Guidelines for Efficient Routing Methods.

International Service Statistics

  1. E.401 (11/88)
    Statistics for the international telephone service (number of circuits in operation and volume of traffic).

International Network Management

  1. E.410 (03/98)
    International network management - General information.
  2. E.411 (03/00)
    International network management - Operational guidance.
  3. E.412 (03/98)
    Network management controls.
  4. E.413 (11/88)
    International network management - Planning.
  5. E.414 (11/88)
    International network management - Organization.
  6. E.415 (08/91)
    International network management guidance for common channel signalling system No. 7.
  7. E.416 (03/00)
    Network Management Principles and Functions for B-ISDN Traffic.

Checking the Quality of the International Telephone Service

  1. E.420 (11/88)
    Checking the quality of the international telephone service - General considerations.
  2. E.421 (11/88)
    Service quality observations on a statistical basis.
  3. E.422 (02/96)
    Observations on international outgoing telephone calls for quality of service.
  4. E.423 (11/88)
    Observations on traffic set up by operators.
  5. E.424 (10/92)
    Test calls.
  6. E.425 (11/98)
    Internal automatic observations.
  7. E.426 (10/92)
    General guide to the percentage of effective attempts which should be observed for international telephone calls.
  8. E.427 (11/88)
    Collection and statistical analysis of special quality of service observation data for measurements of customer difficulties in the international automatic service.
  9. E.428 (10/92)
    Connection retention.
  10. E.430 (06/92)
    Quality of service framework.
  11. E.431 (06/92)
    Service quality assessment for connection set-up and release delays.
  12. E.432 (06/92)
    Connection quality.
  13. E.433 (06/92)
    Billing integrity.
  14. E.434 (06/92)
    Subscriber-to-subscriber measurement of the public switched telephone network.
  15. E.436 (03/98)
    Customer Affecting Incidents and Blocking Defects Per Million.
  16. E.437 (05/99)
    Comparative Metrics for Network Performance.
  17. E.438 (03/00)
    Performance Parameters and Measurement Methods to Assess N-ISDN 64 kbit/s Circuit Switched Bearer Service UDI in Operation.
  18. E.439 (03/00)
    Test Call Measurement to Assess N-ISDN 64 kbit/s Circuit Switched Bearer Service UDI in Operation.
  19. E.440 (02/96)
    Customer satisfaction point.
  20. E.450 (03/98)
    Facsimile quality of service on PSTN - General aspects.
  21. E.451 (03/93)
    Facsimile call cut-off performance.
  22. E.452 (03/93)
    Facsimile modem speed reductions and transaction time.
  23. E.453 (08/94)
    Facsimile image quality as corrupted by transmission-induced scan line errors.
  24. E.454 (10/96)
    Transmission performance metrics based on Error Correction Mode (ECM) facsimile.
  25. E.456 (03/98)
    Test transaction for facsimile transmission performance.
  26. E.457 (02/96) Facsimile measurement methodologies.
  27. E.458 (02/96)
    Figure of merit for facsimile trasnsmission performance.
  28. E.459 (03/98)
    Measurements and Metrics for Characterizing Facsimile Transmission Performance Using Non-Intrusive Techniques.
  29. E.460 (03/00)
    Measurements and Metrics for Monitoring the Performance of V.34 Group 3 Facsimile.

Measurement and Recording of Traffic

  1. E.490 (06/92)
    Traffic measurement and evaluation - General survey.
  2. E.491 (05/97)
    Traffic measurement by destination.
  3. E.492 (02/96)
    Traffic reference period.
  4. E.493 (02/96)
    Grade of service (GOS) monitoring.
  5. E.500 (11/98)
    Traffic intensity measurement principles.
  6. E.501 (05/97)
    Estimation of traffic offered in the network.
  7. E.502 (06/92)
    Traffic measurement requirements for digital telecommunication exchanges.
  8. E.503 (06/92)
    Traffic measurement data analysis.
  9. E.504 (11/88)
    Traffic measurement administration.
  10. E.505 (06/92)
    Measurements of the performance of common channel signalling network.

Forecasting of Traffic

  1. E.506 (06/92)
    Forecasting international traffic.
  2. E.507 (11/88)
    Models for forecasting international traffic.
  3. E.508 (10/92)
    Forecasting new telecommunication services.

Determination of the Number of Circuits in Manual Operation

  1. E.510 (11/88)
    Determination of the number of circuits in manual operation.

Determination of the Number of Circuits in Automatic and Semiautomatic

  1. E.520 (11/88)
    Number of circuits to be provided in automatic and/or semiautomatic operation, without overflow facilities.
  2. E.521 (11/88)
    Calculation of the number of circuits in a group carrying overflow traffic.
  3. E.522 (11/88)
    Number of circuits in a high-usage group.
  4. E.523 (11/88)
    Standard traffic profiles for international traffic streams.
  5. E.524 (05/99)
    Overflow approximations for non-random inputs.
  6. E.525 (06/92)
    Designing networks to control grade of service.
  7. E.526 (03/93)
    Dimensioning a circuit group with multi-slot bearer services and no overflow inputs.
  8. E.527 (03/00)
    Dimensioning at a circuit group with multi-slot bearer services and overflow traffic.
  9. E.528 (02/96)
    Dimensioning of digital circuit multiplication equipment (DCME) systems.
  10. E.529 (05/97)
    Network Dimensioning Using End-to-End GOS Objectives.

Grade of Service

  1. E.540 (11/88)
    Overall grade of service of the international part of an international connection.
  2. E.541 (11/88)
    Overall grade of service for international connections (subscriber-to-subscriber).
  3. E.543 (11/88)
    Grades of service in digital international telephone exchanges.
  4. E.550 (03/93)
    Grade-of-service and new performance criteria under failure conditions in international telephone exchanges.


  1. E.600 (03/93)
    Terms and definitions of traffic engineering.
  2. E.651 (03/00)
    Reference Connections for Traffic Engineering of IP Access Networks.
  3. E.671 (03/00)
    Post-Selection Delay in PSTN/ISDN Networks Using Internet Telephony for a Portion of the Connection.

ISDN Traffic Engineering

  1. E.700 (10/92)
    Framework of the E.700-Series Recommendations.
  2. E.701 (10/92)
    Reference connections for traffic engineering.
  3. E.710 (10/92)
    ISDN traffic modelling overview.
  4. E.711 (10/92)
    User demand modelling.
  5. E.712 (10/92)
    User plane traffic modelling.
  6. E.713 (10/92)
    Control plane traffic modelling.
  7. E.716 (10/96)
    User demand modelling in Broadband-ISDN.
  8. E.720 (11/88)
    ISDN grade of service concept.
  9. E.721 (05/99)
    Network grade of service parameters and target values for circuit-switched services in the evolving ISDN.
  10. E.723 (06/92)
    Grade-of-service parameters for Signalling System No.7 networks.
  11. E.724 (02/96)
    GOS parameters and target GOS objectives for IN services.
  12. E.726 (03/00)
    Network Grade of Service Parameters and Target Values for B-ISDN.
  13. E.728 (03/98)
    Grade-of-Service Parameters for B-ISDN Signalling.
  14. E.730 (10/92)
    ISDN dimensioning methods overview.
  15. E.731 (10/92)
    Methods for dimensioning resources operating in circuit switced mode.
  16. E.733 (11/98)
    Methods for dimensioning resources in Signalling System No. 7 networks.
  17. E.734 (10/96)
    Methods for allocating and dimensioning Intelligent Network (IN) resources.
  18. E.735 (05/97)
    Framework for Traffic Control and Dimensioning in B-ISDN.
  19. E.736 (03/00)
    Methods for Cell Level Traffic Control in B-ISDN.
  20. E.737 (05/97)
    Dimensioning Methods for B-ISDN.
  21. E.743 (04/95)
    Traffic measurements for SS No. 7 dimensioning and planning.
  22. E.744 (10/96)
    Traffic and congestion control requirements for SS No. 7 and IN-structured networks.
  23. E745 (03/00)
    Cell Level Measurement Requirements for the B-ISDN.

Mobile Network Traffic Engineering

  1. E.750 (03/00)
    Introduction to the E.750-Series of Recommendations on traffic engineering aspects of networks supporting mobile and UPT services.
  2. E.751 (02/96)
    Reference connections for traffic engineering of land mobile networks.
  3. E.752 (10/96)
    Reference connections for traffic engineering of maritime and aeronautical systems.
  4. E.755 (02/96)
    Reference connections for UPT traffic performance and GOS.
  5. E.760 (03/00)
    Terminal Mobility Traffic Modelling.
  6. E.770 (03/93)
    Land mobile and fixed network interconnection traffic grade of service concept.
  7. E.771 (10/96)
    Network grade of service parameters and target values for circuit-switched land mobile services.
  8. E.773 (10/96)
    Maritime and aeronautical mobile grade of service concept.
  9. E.774 (10/96)
    Network grade of service parameters and target values for maritime and aeronautical mobile services.
  10. E.775 (02/96)
    UPT grade of service concept.
  11. E.776 (10/96)
    Network grade of service parameters for UPT.

Terms and Definitions Related to the Quality of Telecommunication Services

  1. E.800 (08/94)
    Terms and definitions related to quality of service and network performance including dependability.
  2. E.801 (10/96)
    Framework for service quality agreement.

Models for Telecommunication Services

  1. E.810 (10/92)
    Framework of the Recommendations on the serveability performance and service integrity for telecommunication services.
  2. E.820 (10/92)
    Call models for serveability and service integrity performance.
  3. E.830 (10/92)
    Models for the specification, evaluation and allocation of serveability and service integrity.

Objectives for Quality of Service and Related Concepts of Telecommunication

  1. E.845 (11/88)
    Connection accessibility objective for the international telephone service.
  2. E.846 (03/93)
    Accessibility for 64 kbit/s circuit switched international end-to-end ISDN connection types.
  3. E.850 (10/92)
    Connection retainability objective for the international telephone service.
  4. E.855 (11/88)
    Connection integrity objective for the international telephone service.

Use of Quality of Service Objectives for Planning of Telecommunication

  1. E.862 (06/92)
    Dependability planning of telecommunication networks.

Field Data Collection and Evaluation on the Performance of Equipment,

  1. E.880 (11/88)
    Field data collection and evaluation on the performance of equipment, networks and services.