WPCL 2BJ|x  H   x|@  6'6' Recommendation I.251 Number identification supplementary services HThe purpose of this Recommendation is to provide the stage 1 description of the method defined in Recommendation I.130 using the means given in Recommendation I.210.   HSupplementary services are described by a prose definition and description (step 1.1) and by a dynamic description (step 1.3). The application of the attribute technique, as defined in RecommendationI.140, for supplementary services is for further study.  ( HThis Recommendation describes the following Number Identification Supplementary Services: HI.251.1 Direct Dialling In (DDI) HI.251.2 Multiple Subscriber Number (MSN) HI.251.3 Calling Line Identification Presentation (CLIP) HI.251.4 Calling Line Identification Restriction (CLIR) HI.251.5 Connected Line Identification Presentation (COLP) HI.251.6 Connected Line Identification Restriction (COLR) HI.251.7 Malicious Call Identification (MCI) (Note1) HI.251.8 Subaddressing (SUB) (Note 1)   Note 1 These services being identified need to be further studied and the descriptions are not yet included. I.251.1 Direct Dialling In 1.HDefinition HDirect Dialling In (DDI) enables a user to directly call another user on a ISPBX or other private system without attendant intervention. 2.HDescription 2.1HGeneral description HA part of the ISDN number, which is significant to the called user, is passed to that user during call establishment. This supplementary service is based on the use of the ISDN number and does not include subaddressing.   Note 1 A similar method to select a terminal on a passive bus is described in the supplementary service MSN. Note 2 The caller may or may not find the ISDN number in the public directory. 2.2HSpecific terminology HNone. 2.3HQualifications on the applicability to telecommunications services HNo restrictions. 3.HProcedures 3.1HProvision/withdrawal HThis service shall be provided/withdrawn after prearrangement with the service provider. The service provider shall allocate a set of ISDN numbers. 3.2HNormal procedures 3.2.1HActivation/deactivation/registration HActivation through subscription. 3.2.2HInvocation and operation HCall initiation procedures are the same as for the basic service. The calling and called users perceive the same completion procedures as for the basic service, without attendant intervention. Upon answer, the calling user is connected to the called user designated by the ISDN number. Note When the connection from the caller to the ISPBX is established, the called ISPBX might use the connection for call progress signalling transmission. 3.3HExceptional procedures 3.3.1HActivation/deactivation/registration HNot applicable. 3.3.2HInvocation and operation HIf the called user is busy or does not answer, the procedures for basic calls will apply. HIf a call is made by sending incomplete address information, the call will be released by time supervision within the public exchange. A corresponding time supervision within the ISPBX may also be convenient. 3.4HAlternate procedures 3.4.1HActivation/deactivation/registration HNot identified. 3.4.2HInvocation and operation HNot identified. 4.HNetwork capabilities for charging HThis Recommendation does not cover charging principles. Future Recommendations in the DSeries are expected to contain that information. It shall be possible to charge the subscriber accurately for the service. For example, supplementary service provision may be part of the general subscription charges. Charges may include a subscription fee and a rental charge proportional to the quantity of numbers assigned. 5.HInterworking requirements HNo problems identified.  ,Ԍ6.HInteraction with other supplementary services 6.1HCall Waiting HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.2HCall Transfer HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.3HConnected Line Identification Presentation HFor further study. 6.4HConnected Line Identification Restriction HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.5HCalling Line Identification Presentation HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.6HCalling Line Identification Restriction HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.7HClosed User Group HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.8HConference Calling HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.9HDirect Dialling In HNot applicable. 6.10HDiversion services 6.10.1 Call Forwarding Busy HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.10.2 Call Forwarding No Reply HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.10.3 Call Forwarding Unconditional HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.11HLine Hunting HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.12HThreeParty Service HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.13HUsertoUser Signalling HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.14HMultiple Subscriber Number HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.15HCall Hold Service HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.16HAdvice of Charge HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 7.HDynamic description HThe dynamic description is as for basic services. I.251.2 Multiple Subscriber Number 1.HDefinition HMultiple Subscriber Number (MSN) provides the possibility for assigning multiple ISDN numbers to a single interface. This allows e.g. H1)h  to dial from a line connected to a public network directly to terminals connected to a basic access which has subscribed to MSN (e.g. in a passive bus configuration); H2)h  the network to determine which ISDN number is applicable on originating calls, e.g. for charging purposes, for notification to the called party and application for supplementary services. HIt is considered: H that some administrations may not have knowledge or control over what is connected to the basic access, e.g. an NT2 or passive bus; H that administrations have differing numbering methods; H that common international terminal specifications are desired. 2.HDescription  ,Ԍ2.1HGeneral description HThe addressing of terminals on a basic access may be achieved by applying a set of ISDN numbers to the single basic access. When a call with one of these ISDN numbers is delivered, the called number is indicated to the MSN user, either directly or through a mapping by the network. HIn general, any set of numbers may be sent from the network to the subscriber's equipment during call establishment. However, it is recognized that administrative practices and certain equipment designs may lead to the adoption of restricted numbering sequences, e.g. by relating the last digit(s) of a fixed length ISDN number to the terminals to be connected. The actual method of relating the ISDN number to a particular terminal is a matter of national implementation but may, for example, be done by central intelligence or by distributed intelligence within the terminals. HThe essential difference between this supplementary service and DDI concerns the length of the number sent to and processed by the user's installation. In the DDI situation the user (ISPBX) will be tailored on a per installation basis to receive the particular number of digits necessary to identify the terminals of this user (ISPBX). HWith the multiple subscriber number supplementary service however, the service provider will fix the length of the number to be transmitted to the user's installation. It may comprise 1 or 2 or 3 of the last digits up to the full ISDN number. This number will be sent to the user network interface. HThe digit(s) significant for terminal differentiation is/are an integral part of the ISDN numbering scheme. Note MSN is independent from and does not impose any constraints on "service indication" and "subaddressing". 2.2HSpecific terminology HNone. 2.3HQualifications on the applicability to telecommunications services HNo restrictions. 3.HProcedures 3.1HProvision/withdrawal HThe service shall be provided after prearrangement with the service provider. HThe service provider shall allocate a set of ISDN numbers (not necessarily consecutive). At the option of the service provider, one of these numbers may be designated by the MSN subscriber as the default number for the interface. At the option of the service provider, the user may specify a mapping arrangement between ISDN number and MSN digit(s). 3.2HNormal procedures 3.2.1HActivation/deactivation/registration HActivation through subscription. 3.2.2HInvocation and operation HThe destination number sent by the calling user will be analyzed in the network. If the called user subscribes to this supplementary service, the network sends the available part of the ISDN number or at least the relating digit(s) Hi)h  identical to that last digit(s) of the ISDN number; or Hii)  generated by the network on the basis of a mapping process between ISDN number(s) and MSN digit(s). HTerminals compatible to the MSN service will react on a call as follows: H if MSN digit(s) equal to their own preadjusted identity is (are) presented, they react to it in a predetermined way; H if there is a setup message without MSN digit(s), the terminal will interpret it as a normal call. (This may happen if a terminal with MSN capabilities is used on an interface, where MSN is not subscribed for.) HTerminals not compatible to the MSN service will react on a call as follows: H either if there is (are) MSN digit(s) or not, the call will be interpreted as a normal call. HOn outgoing calls a terminal compatible with the MSN service may provide the ISDN number (or MSN digits) when placing the call. The network will carry this identity unchanged or will replace the digit(s) by the associated ISDN number. The ISDN number of the calling terminal will then be sent to the called user with the incoming call (refer to CLIP supplementary service). HIt is possible to allocate one ISDN number to one or more terminals. Similarly, one terminal may allow the assignment of one or more than one number. Further, as an administrative option a specific digit or sequence of digits may be allocated to enable all terminals in a pointtomultipoint configuration to react in the same way as if the supplementary service MSN would not be subscribed to. 3.3HExceptional procedures 3.3.1HActivation/deactivation/registration HNot applicable. 3.3.2HInvocation and operation HAn ISDN number or MSN digits, generated by a terminal at an interface where MSN is in operation shall be discarded by the network unless this number is subscribed to by this interface. A default number may be provided by the network. 3.4HAlternative procedures 3.4.1HActivation/deactivation/registration HNone identified. 3.4.2HInvocation and operation HNone identified.  ,Ԍ4.HNetwork capabilities for charging HThis Recommendation does not cover charging principles. Future Recommendations in the DSeries are expected to contain that information. It shall be possible to charge the subscriber accurately for the service. 5.HInterworking requirements HNone identified. 6.HInteraction with other supplementary services HIn case of interaction with other supplementary services, these services could be applicable to the individual MSN rather than to the subscriber access. 6.1HCall Waiting HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.2HCall Transfer HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.3HConnected Line Identification Presentation HSee COLP (I.251.5) interaction with MSN. 6.4HConnected Line Identification Restriction HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.5HCalling Line Identification Presentation HUpon call initiation, if the ISDN number indicated by the MSN user terminal is not subscribed to for the interface, or if no numbering information is indicated, a default number (if designated by the MSN subscriber) or a number unavailable indication is provided to the CLIP user. 6.6HCalling Line Identification Restriction HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.7HClosed User Group HFor further study. 6.8HConference Calling HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.9HDirect Dialling In HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.10HDiversion services 6.10.1 Call Forwarding Busy HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.10.2 Call Forwarding No Reply HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.10.3 Call Forwarding Unconditional HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.11HLine Hunting HFor further study. 6.12HThreeParty Service HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.13HUsertoUser Signalling HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.14HMultiple Subscriber Number HNot applicable. 6.15HCall Hold Service HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.16HAdvice of Charge HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 7.HDynamic description HThe dynamic description is as for the basic services. I.251.3 Calling Line Identification Presentation 1.HDefinition HCalling Line Identification Presentation (CLIP) is a supplementary service offered to the called party which provides the calling party's ISDN number, possibly with subaddress information, to the called party. 2.HDescription 2.1HGeneral description HWhen CLIP is applicable and activated, the network provides the called , party with the number of the calling party at call setup on all incoming calls. HThe calling party number may be accompanied by a subaddress. HThe network should be capable of transmitting at least 15 digits (maximum length of an ISDN number). In addition, if provided by the calling party, the network should be capable of transmitting a subaddress. HThe network to which the calling party belongs should attempt to ensure that enough digits are transmitted to enable the called party to return the call, based on the calling number presented. 2.2HSpecific terminology HNone identified. 2.3HQualifications on the applicability to telecommunication services HThis supplementary service is applicable to all telecommunication services. HIt is to be noted that in the Telematic services an exchange of Terminal Identification (TID) occurs at a higher layer subsequent to a successful call establishment. HFor Telematic services this supplementary service shall consist only of the access number of the calling party and this shall be provided by the network. For other nonvoice services this supplementary service is for further study. The presentation of the calling party's ISDNnumber by Telematic terminals and by other nonvoice terminals is for further study. 3.HProcedures 3.1HProvision/withdrawal HCLIP may be provided on a subscription basis or be generally available. CLIP may be withdrawn at the request of the subscriber or by the network provider for administration reasons. 3.2HNormal procedures 3.2.1HActivation/deactivation/registration HCLIP is activated on provision and deactivated on withdrawal. No information needs to be registered with the network for this supplementary service. 3.2.2HInvocation and operation HThe number presented shall unambiguously identify the access of the calling party. The number presented is either: Hi)h  completely provided by the network; Hii)  completely provided by the calling party; or HHX HHiii) partially provided by the network with the rest provided by the calling party, e.g., the access number is provided by the network and the additional digits to make the number complete by the calling party. HWhere either the complete calling number, or part of the calling number is initially provided by the calling party, the network shall check its validity. If this check is successful, then this number is used by the network. For complete calling numbers, this validity check shall determine whether the number is allocated to the access; for partially provided numbers this check shall for example, determine whether the digits are within the allocated range. 3.3HExceptional procedures 3.3.1HActivation/deactivation/registration HNone identified. 3.3.2HInvocation and operation HIf the network check on a calling party provided number is unsuccessful, the network will use the default number as the number of the calling party. HThere are two exceptions when the calling party number is not presented to the called party: Hi)h  when the calling party has an arrangement (see definition of Calling Line Identification Restriction) that presentation of his number is not allowed; and Hii)  when the calling party number is not available, e.g., due to interworking with the analogue telephone network (PSTN). HIn such cases no number is presented to the called party, but he shall receive an indication that the number of the calling party is unavailable. 3.4HAlternative procedures 3.4.1HActivation/deactivation/registration HNone identified. 3.4.2HInvocation and operation HIn some cases where a calling party has an arrangement that presentation of his number is not allowed, there may be certain categories of called party that have the ability to override this restriction and have the calling number presented. This function is a national option. HProblems may occur when the calling party does not belong to the same network as the called party and in the calling party's network the override category does not exist, but in the called party's network this category does exist. A problem occurs when a calling party who restricts presentation and assumes that his number is never presented, makes a call to a called party who has the override category. HThe cases where the override category is applied is a national matter. Depending on bilateral agreement about the application of the override category in country B, and the presentation not allowed arrangement of the calling party in country A, country A may or may not deliver the calling line identification to country B. Agreements are also needed with any transit network. 4.HNetwork capabilities for charging HThis Recommendation does not cover charging principles. Future Recommendations in the DSeries are expected to contain that information. It shall be possible to charge the subscriber accurately for the service. ,Ԍ 5.HInterworking requirements HOn calls incoming from some nonISDN networks, the calling number may be delivered to the destination ISDN without the ability to indicate whether presentation is allowed or not. How the ISDN should behave in this case is for further study. HFrom some other nonISDN networks, no calling party number may be available to the ISDN and therefore the full number of the calling party cannot be given to the called party who has been provided with CLIP. In this situation a partial number, or a number unavailable indication, is given to the called party. HAs a national option, the originating network shall have the possibility to restrict any information identifying the calling party from being forwarded to another network. If a destination network receives a calling party ISDN number without any indication of presentation allowed or restricted, the destination network (host network) will act according to its own rules and regulations. 6.HInteraction with other supplementary services 6.1HCall Waiting HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. HIf an ISDN User(s) who has subscribed to the Call Waiting service at his B access, has been given a call waiting indication and has subscribed to the CLIP service, then the calling party's number shall be presented to the ISDN User(s) at B at the time the call waiting indication is given. The presentation of the CLIP information shall be the same as when the ISDN User(s) at B receives a normal call. 6.2HCall Transfer HSee text in 6.5, CLIP, in the Call Transfer supplementary service definition. 6.3HConnected Line Identification Presentation HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.4HConnected Line Identification Restriction HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.5HCalling Line Identification Presentation HNot relevant. 6.6HCalling Line Identification Restriction HThe calling line identification will not be presented if the calling user has an arrangement to inhibit the presentation of his number to the called party. The only occasion when a user subscribing to CLIP can take precedence over CLIR is when the user has an override category. This is a national option. 6.7HClosed User Group HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.8HConference Calling HAny party that has subscribed to CLIP will receive the number of a calling conference controller when: H the party is to be included as a "New Party" during the invocation of a conference call; or H the party is being added to an existing conference call. 6.9HDirect Dialling In HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.10HDiversion services HIf an incoming call to the party to which CLIP has been provided has already been forwarded, then the calling party's number should be the number of the original calling party. 6.10.1 Call Forwarding Busy HSee text in Call Forwarding Busy for further information. 6.10.2 Call Forwarding No Reply HSee text in Call Forwarding No Reply for further information. 6.10.3 Call Forwarding Unconditional HSee text in Call Forwarding Unconditional for further information. 6.11  Line Hunting HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. HThe Line Hunting service occurs before CLIP. The Line Hunting service would first provide a selection of an interface for presentation of a call. Once the service selects an interface, normal call processing would occur including the presentation of the calling party's number to a selected interface who has subscribed to CLIP. 6.12HThreeParty Service HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.13HUsertoUser Signalling HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.14HMultiple Subscriber Number HSee text in Multiple Subscriber Number definition.  ,Ԍ6.15HCall Hold Service HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.16HAdvice of Charge HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 7.HDynamic description HThe dynamic description for this service is shown in Figure1/I.251.3. I.251.4 Calling Line Identification Restriction 1.HDefinition HCalling Line Identification Restriction (CLIR) is a supplementary service offered to the calling party to restrict presentation of the calling party's ISDNnumber and SubAddress to the called party. 2.HDescription 2.1HGeneral description HWhen CLIR is applicable and activated the originating node provides the destination node with a notification that the calling party's ISDN number and any SubAddress information, is not allowed to be presented to the called party. In this case no calling party number is included in the call offering to the called party's installation. Note When CLIR is subscribed to, some Network Providers may not wish to send the originating identity of the calling customer to other Network Providers. 2.2HSpecific terminology HNone identified. 2.3HQualifications on the applicability to telecommunications services HNone identified, i.e., this supplementary service is applicable to all telecommunication services. 3.HProcedures 3.1HProvision/withdrawal HCLIR can be provided on a subscription basis or be generally available. HAs a network provider option, CLIR can be offered with several subscription options. The options apply separately to each ISDN number. Subscription options are summarized below: HSubscription Option Values HCLIR mode permanent (active for all calls) temporary (specified by user per call) Default (only for temporary mode) presentation restricted presentation not restricted HIt is a network provider option to specify either or both of the above options for all subscribers, for instance, in an exchange or network. 3.2HNormal procedures 3.2.1HActivation/deactivation/registration HIf subscribed to in the permanent mode, CLIR is always activated. If subscribed to on a temporary basis, CLIR is activated upon explicit request for the service, or on default, on a particular call and is deactivated after that call. 3.2.2  Invocation and operation HIf the called party subscribes to Calling Line Identification Presentation and the calling party has CLIR activated, the called party shall receive an indication that the calling party number is not available. 3.3HExceptional procedures 3.3.1HActivation/deactivation/registration HNo exceptional procedures identified. 3.3.2HInvocation and operation HNo exceptional procedures identified. 3.4HAlternative procedures 3.4.1HActivation/deactivation/registration HNo alternative procedures identified. 3.4.2HInvocation and operation HCertain countries may define categories of subscribers that have the ability to override the presentation restriction and have the calling party's ISDN , number and any SubAddress presented (e.g., the police). HThe ability to have such override category is a national option. HWhen a call originates in one ISDN and terminates in another ISDN and CLIR is applied, the rules and regulations of the destination network (the host network) should apply. For example, if override category is not applicable in the originating network but in the destination network a call with CLIR applied can still be overridden in the destination network, whenever information on the calling line is available for this network. 4.HNetwork capabilities for charging HThis Recommendation does not cover charging principles. Future Recommendations in the DSeries are expected to contain that information. It shall be possible to charge the subscriber accurately for the service. 5.HInterworking requirements HOn calls to or via nonISDNs, it cannot be assured that a CLIR indication can be carried to the destination network. As a national option the originating network shall have the possibility to restrict any information identifying the calling party from being forwarded to the destination network when CLIR is applicable. If a network receives a calling party ISDN number without any indication of presentation allowed or restricted, the destination network (the host network) will act according to its rules and regulations. 6.HInteraction with other supplementary services 6.1HCall Waiting HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. HAssume that a call from a User at C, who has subscribed to the CLIR service, invokes Call Waiting at a User(s) at B. The User(s) at B would receive a call waiting indication but would not receive the calling User at C's number when the call waiting indication is given. 6.2HCall Transfer HAssume that a User A has an established call with User B and wishes to transfer this call with User B to User C. If User A has subscribed to CLIR, then User C shall not receive a calling number when User A invokes any call transfer procedure. If User B has subscribed to CLIR, then User C shall not receive a calling number during the transfer of User B to User C. 6.3HConnected Line Identification Presentation HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.4HConnected Line Identification Restriction HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.5HCalling Line Identification Presentation HCLIR will take precedence over Calling Line Identification Presentation (CLIP). HThe only occasion when a user subscribing to CLIP can take precedence over CLIR is when the user has an override category. This is a national option. 6.6HCalling Line Identification Restriction HNot relevant. 6.7HClosed User Group HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.8HConference Call HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.9HDirect Dialling In HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.10HDiversion services 6.10.1 Call Forwarding Busy HWhen CLIR is applicable and activated, the calling party's ISDNnumber will not be presented to the "forwardedto" user unless this user has an override category. The latter is a national option. 6.10.2 Call Forwarding No Reply HWhen CLIR is applicable and activated, the calling party's ISDNnumber will not be presented to the "forwardedto" user unless this user has an override category. The latter is a national option. 6.10.3 Call Forwarding Unconditional HWhen CLIR is applicable and activated, the calling party's ISDNnumber will not be presented to the "forwardedto" user unless this user has an override category. The latter is a national option. 6.11HLine Hunting HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.12HThreeParty Service HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. H 6.13 UsertoUser Signalling HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.14HMultiple Subscriber Number HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. ,Ԍ 6.15HCall Hold Service HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.16HAdvice of Charge HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 7.HDynamic description HThe dynamic description for this service is shown in Figure1/I.251.4. I.251.5 Connected Line Identification Presentation 1.HDefinition HConnected Line Identification Presentation (COLP) is a supplementary service offered to the calling party which provides the connected party's ISDN number to the calling party. 2.HDescription 2.1HGeneral description HWhen COLP is applicable and activated, the network provides the calling party with the number of the connected party when the connected party answers the incoming call. The network should be capable of transmitting at least 15 digits (maximum length of an ISDN number). Note The possibility of enhancing this service to provide the called party number before the called party answers the call is for further study. 2.2HSpecific terminology HNone identified. 2.3HQualifications on the applicability to telecommunication services HThis supplementary service is applicable to all telecommunication services. HIt is to be noted that in the Telematic services an exchange of Terminal Identification (TID) occurs at a higher layer subsequent to a successful call establishment. HFor Telematic services this supplementary service shall consist only of the access number of the connected party and this shall be provided by the network. For other nonvoice services this supplementary service is for further study. The presentation of the connected party's ISDN number by Telematic terminals and by other nonvoice terminals is for further study. 3.HProcedures 3.1HProvision/withdrawal HThe COLP supplementary service may be provided on a subscription basis or be generally available. HCOLP may be withdrawn at the request of the subscriber or by the network provider for administration reasons. 3.2HNormal procedures 3.2.1HActivation/deactivation/registration HCOLP is activated on provision and deactivated on withdrawal. HNo information needs to be registered with the network for this supplementary service. 3.2.2  Invocation and operation HThe number presented shall unambiguously identify the access of the connected party. The number presented is either: Hi)h  completely provided by the network; Hii)  completely provided by the connected party; or HHX HHiii) partially provided by the network with the rest provided by the connected party, e.g., the access number is provided by the network and the additional digits to make the number complete by the connected party. HWhere either the complete connected number, or part of the connected number is initially provided by the connected party the network shall check its validity. If this check is successful then this number is used by the network. 3.3HExceptional procedures 3.3.1HActivation/deactivation/registration HNone identified. 3.3.2HInvocation and operation 3.3.2.1 There are two exceptions when the connected party number is not ,  presented to the calling party: Hi)h  when the connected party has (see definition of Connected Line Identification Restriction) an arrangement that presentation of his number is not allowed; or Hii)  when the connected party number is not available, e.g., due to interworking with the (analogue) Public Switched Telephone Network (PSTN). HIn such cases the calling party shall be given a number unavailable indication. HIf the network check on the connected party provided number is unsuccessful, the network default number will be used instead. 3.4HAlternative procedures 3.4.1HActivation/deactivation/registration HNone identified. 3.4.2HInvocation and operation Override category HIn some cases where a connected party has an arrangement that presentation of his number is not allowed, there may be certain categories of calling party that have the ability to override this restriction and have the connected number presented. This function is a national matter. HProblems may occur when the connected party does not belong to the same network as the calling party and in the connected party's network the override category does not exist, but in the calling party's network this category does exist. A problem occurs when a connected party who restricts presentation and assumes that his number is never presented, receives a call from a calling party who has the override category. HThe cases where the override category is applied is a national matter. Depending on bilateral agreement about the application of the override category in country A, and the presentation not allowed arrangement of the connected party in country B, country B may or may not deliver the connected line identification to country A. Agreements are also needed with any transit network. 4.HNetwork capabilities for charging HThis Recommendation does not cover charging principles. Future Recommendations in the DSeries are expected to contain that information. It shall be possible to charge the subscriber accurately for the service. 5.HInterworking requirements HOn calls destined for some nonISDN networks, the connected number may be delivered to the originating ISDN without the ability to indicate whether presentation is allowed or not. How the ISDN should behave in this case is for further study. HOn calls destined for some other nonISDN networks, no connected party number may be available to the ISDN and therefore the full number of the connected party cannot be given to the calling party who has been provided with COLP. In this situation a partial number shall be given unless no information is available whereupon a number unavailable indication is given to the calling party. 6.HInteraction with other supplementary services 6.1HCall Waiting HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.2HCall Transfer HAssume the situation where a User A has an established call with a UserB and wishes to transfer this call with User B to a User C. HExcept in the case where User C prohibits the presentation of his number, User C's number shall be presented: H to User B upon successful completion of the transfer to UserC (independent of the type of transfer procedure invoked by UserA) provided that User B has subscribed to COLP; H to User A when User A is using normal or explicit transfer procedures and has subscribed to COLP. The connected party's number will not be presented to User A if User A invokes the single step Call Transfer procedure. Note that the connected number presentation may not be possible if interworking with a nonISDN network is invoked in the call transfer. 6.3HConnected Line Identification Presentation HNot applicable. 6.4HConnected Line Identification Restriction HThe connected line identification will not be presented if the connected User has subscribed to COLR. 6.5HCalling Line Identification Presentation HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.6HCalling Line Identification Restriction HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.7HClosed User Group HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.8HConference Calling HA Conference Controller who has also subscribed to COLP should be presented with the connected party's number when that party is either part of the initial activation of the conference or is added as a new conferee to an existing conference. HConferees in an existing conference who have subscribed to COLP will not ,  receive a new party's number whenever a conference controller adds a new party to the conference. 6.9HDirect Dialling In HFor further study. 6.10HDiversion services 6.10.1 Call Forwarding Busy (CFB) HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. HAssume a calling User A, who has subscribed to COLP, places a call to a User B who is busy and this call is forwarded to a User C. If User B has also subscribed to a notification option with his CFB service, calling User A may receive the forwardedto User C's number with the notification of the forwarding. In any event, assuming User C answers the call, User C's number will be returned to User A unless User C has subscribed to COLR. 6.10.2 Call Forwarding No Reply (CFNR) HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. HAssume a calling User A, who has subscribed to COLP, places a call to a User B who has subscribed to the CFNR service, and who does not reply to the call within the subscribed time interval. If User B has also subscribed to a notification option with his CFNR service, calling User A may receive the forwardedto User C's number with the notification of the forwarding. In any event, assuming User C answers the call, User C's number will be returned to User A unless User C has subscribed to COLR. 6.10.3 Call Forwarding Unconditional (CFU) HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. HAssume a calling User A, who has subscribed to COLP, places a call to a User B who has subscribed to the CFU service. This call to User B would then be forwarded to User C. If User B has also subscribed to a notification option with his CFU service, calling User A may receive the forwardedto User C's number with the notification of the forwarding. In any event, assuming User C answers the call, User C's number will be returned to User A unless User C has subscribed to COLR. 6.11HLine Hunting HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.12HThreeParty Service HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.13HUsertoUser Signalling HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.14HMultiple Subscriber Number HAssume User A, who has subscribed to COLP, places a call to a User B to which the network is applying the MSN service. Assuming User B answers the call, the connected number at B (which may be identical to the called number) will be returned to User A unless User B has subscribed to COLR. Other interactions are for further study. 6.15HCall Hold Service HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.16 HAdvice of Charge HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 7.HDynamic description HThe dynamic description for this service is shown in Figure 1/I.251.5. I.251.6 Connected Line Identification Restriction 1.HDefinition HConnected Line Identification Restriction (COLR) is a supplementary service offered to the connected party to restrict presentation of the connected party's ISDNnumber to the calling party. 2.HDescription 2.1HGeneral description HWhen COLR is applicable and activated, the destination node provides the originating node with a notification that the connected party's ISDN number is not allowed to be presented to the calling party. In this case no connected party number is included in the call connected information to the calling party's installation. Note When COLR is subscribed to, some Network Providers may not wish to send ,  the identity of the connected customer to other Network Providers. 2.2HSpecific terminology HNone identified. 2.3HQualifications on the applicability to telecommunications services HNone identified, i.e., this supplementary service is applicable to all telecommunication services. 3.HProcedures 3.1HProvision/withdrawal HCOLR can be provided on a subscription basis or be generally available. HAs a network provider option, COLR can be offered with several subscription options. The options apply separately to each ISDN number. Subscription options are summarized below: HSubscription Option Values HCOLR mode permanent (active for all calls) temporary (specified by user per call) HDefault presentation restricted H(only for temporary mode) presentation not restricted HIt is a network provider option to specify either or both of the above options for all subscribers, for instance, in an exchange or network. 3.2HNormal procedures 3.2.1HActivation/deactivation/registration HIf subscribed to in the permanent mode, COLR is always activated. If subscribed to on a temporary basis, COLR is activated upon explicit request for the service, or on default, on a particular call and is deactivated after that call. 3.2.2  Invocation and operation HIf the calling party subscribes to Connected Line Identification Presentation and the connected party has COLR activated, the calling party shall receive an indication that the connected party number is not available. 3.3HExceptional procedures 3.3.1HActivation/deactivation/registration HNo exceptional procedures identified. 3.3.2HInvocation and operation HNo exceptional procedures identified. 3.4HAlternative procedures 3.4.1HActivation/deactivation/registration HNo alternative procedures identified. 3.4.2HInvocation and operation HCertain countries may define categories of subscribers that have the ability to override the presentation restriction and have the connected party's ISDN number presented (e.g., the police). HThe ability to have such override category is a national option. HWhen a call originates in one ISDN and terminates in another ISDN and COLR is applied, the rules and regulations of the destination network (the host network) should apply. For example, if override category is not applicable in the originating network but in the destination network a call with COLR applied can still be overridden in the destination network, whenever information on the connected line is available for this network. 4.HNetwork capabilities for charging HThis Recommendation does not cover charging principles. Future Recommendations in the DSeries are expected to contain that information. It shall be possible to charge the subscriber accurately for the service. 5.HInterworking requirements HOn calls to or via nonISDNS, it cannot be assured that a COLR indication can be carried to the originating network. As a national option the destination network shall have the possibility to restrict any information identifying the connected party from being returned to the originating network when COLR is applicable. If a network receives a connected party ISDN number without any indication of presentation allowed or restricted, the originating network (the host network) will act according to its rules and regulations. 6.HInteraction with other supplementary services 6.1HCall Waiting HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. HAssume that a call from a User at C, invokes Call Waiting at UserB, who has subscribed to the COLR service. The UserB would receive a call waiting indication but would not have his number returned when the call waiting indication is given. 6.2HCall Transfer HAssume that User A has an established call with UserB and wishes to transfer this call with UserB to a UserC. HIf UserC has subscribed to COLR, then User A shall not receive the connected number when UserA invokes any call transfer procedure. If UserC has subscribed to COLR, then UserB shall not receive the connected number during the transfer of UserB to UserC. 6.3HConnected Line Identification Presentation HCOLR will take precedence over COLP. The only occasion when a User subscribing to COLP can take precedence over COLR is when the User has an override category. This is a national option.  , Ԍ6.4HConencted Line Identification Restriction HNot relevant. 6.5HCalling Line Identification Presentation HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.6HCalling Line Identification Restriction HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.7HClosed User Group HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.8HConference Call HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.9HDirect Dialling In HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.10HDiversion services 6.10.1 Call Forwarding Busy HWhen the diverted call is finally answered, no connected number will be presented to the calling party unless this party has an override category. The latter is a national option. 6.10.2 Call Forwarding No Reply HWhen the diverted call is finally answered, no connected number will be presented to the calling party unless this party has an override category. The latter is a national option. 6.10.3 Call Forwarding Unconditional HWhen the diverted call is finally answered, no connected number will be presented to the calling party unless this party has an override category. The latter is a national option. 6.11HLine Hunting HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.12HThreeParty Service HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.13HUsertoUser Signalling HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.14HMultiple Subscriber Number HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.15HCall Hold Service HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 6.16 HAdvice of Charge HNo impact, i.e. neither supplementary service affects the operation of the other supplementary service. 7.HDynamic description HThe dynamic description for this service is shown in Figure 1/I.251.6. I.251.7 Malicious Call Identification HThese services being identified need to be further studied and the descriptions are not yet included. I.251.8 Subaddressing HThese services being identified need to be further studied and the descriptions are not yet included.