A statement issued by the Director General of Telecommunications

February 2000

Contents

Summary

Chapter 1     Introduction

Chapter 2     Type 3 presentation numbers

Chapter 3     Safeguards

Chapter 4     Special arrangements

Annex A       Respondents

Annex B       Responses

Annex C       Indicative questions

Annex D       A Special Arrangements contract

Annex E       Proposed class licence condition

Annex F       Types of presentation number

Glossary

Summary

S1 In March 1999 Oftel consulted on the use of presentation numbers within Calling Line Identification (CLI) service. In particular, the consultation examined the potential usefulness of a special type of presentation number (type 3) which is not checked automatically by the network. Up to now Oftel rules have prevented callers from using these. This statement sets out Oftel’s proposals for revised rules on the use of presentation numbers in the light of that consultation.

The problem

S2 The current rules only allow the use of presentation numbers which can be checked or verified by the network. This restriction was intended to protect customers from receiving misleading CLI information. However it has had the opposite effect where calls are made from extensive private networks. The requirement that a caller's CLI is checked at the point where the call breaks out on to a public network results in a displayed CLI which does not give the customer a meaningful number by which to recognise or return the call.

S3 To avoid this, many companies simply withhold their CLI. This is not a satisfactory solution and will become even less so when, from March, European legislation will require operators to offer their customers a service which will automatically reject calls where the CLI has been withheld – Anonymous Call Rejection (ACR). Companies that withhold their CLI will then find that they cannot get through to customers where those customers have opted for ACR.

Consultation

S4 The consultation reviewed the balance of consumer advantage in allowing in future the use of what are known as type 3 presentation numbers. These are numbers delivered by a caller’s equipment to the local exchange which present a useful diallable number to the called customer but which cannot be immediately verified by a network operator. The document proposed, however, that permission to use them would enable some callers to overcome the problems they will face in getting their calls connected when ACR becomes available.

Proposals

S5 Oftel has concluded that the opportunities and convenience offered by the use of these presentation numbers would be of benefit to all telephone users, not just those able to send them. The Statement therefore proposes that network operators should be allowed to offer certain calling parties the facility of using type 3 presentation numbers.

S6 With the ability to insert their own presentation numbers callers will no longer have to remain anonymous. They also avoid the risk of having their calls rejected where the called party has subscribed to an ACR service. For people and organisations receiving calls the benefits are equally clear. Type 3 presentation numbers will offer useful information about a caller's identity where at present the CLI information is either unavailable or downright misleading. Moreover customers choosing an ACR service will now be able to receive calls that would not have been connected. These advantages more than outweigh any potential uncertainty about the authenticity of the number presented

S7 However in response to the concerns expressed by some consumer groups and the need to maintain public confidence in CLI services Oftel has decided that the safeguards originally proposed should be made stronger. They now include:

• a direct role for Oftel in deciding which subscribers should be allowed to send type 3 PNs, to be reviewed after 18 months;

• type 3 presentation numbers will not be available to individual users but only to companies or other organisations making use of extended private networks;

• a requirement that calling parties take responsibility for the correct configuration of their equipment to deliver authentic CLI numbers;

• a requirement that calling parties nominate the numbers they intend to use as presentation numbers and inform their operator of any changes in the allocation of those numbers;

• a requirement on operators to maintain lists of nominated numbers which will be open to Oftel scrutiny;

• a new class licence condition requiring users to ensure that only authentic CLIs are used.

S8 With this enhanced level of safeguards Oftel is confident that it has achieved the right balance. The proposals will offer users the advantages of a wider range of CLI products while maintaining their confidence in the essential trustworthiness of this service.

Chapter 1

Introduction

1.1 In March, Oftel published a consultation document, Presentation numbers : the development of calling line identification services in the UK. This was followed by a Workshop in June on the issues raised organised by Consumer Communications for England (CCE), one of Oftel's Advisory Committees. The purpose of the consultation was to assess the advantages and disadvantages that would arise from permitting the use of a special type of presentation number, known as a type 3 presentation number. This type of number had previously been prohibited because it was not possible for networks to verify the authenticity of numbers supplied by a calling party's equipment, rather than applied by the operator at the point where calls enter the public telephone network. Although this sounds as if it is only a narrow technical question, in reality it is a significant issue for all telephone users. Doing nothing is an option that could carry serious consequences, given the new requirements which EU data protection legislation will shortly place on telecoms operators.

The problem

1.2 Underlying this initiative was the interaction of two separate developments. Firstly, the difficulty of ascribing a useful CLI to a call that breaks out of a private network outside the area it was made from. Within a large private network a call may be routed the length or breadth of the country. When that call passes over to the public network the CLI it carries will identify where it entered the public network, not where the caller is calling from. So a call made from a Cardiff tax office to a Birmingham taxpayer could present a Birmingham number as the CLI. This CLI information will be largely useless – it gives the person being called (for the purposes of this Statement identified as the customer) misleading information about the caller and can result in an attempt to return the call to a number where nobody knows anything about the original call.

1.3 To avoid presenting misleading information in this way many organisations feel they have no choice but to withhold their CLI where outgoing calls are routed through private networks. This is bad enough – many people dislike receiving anonymous calls – but made more damaging by the second development.

1.4 This is the imminent availability of Anonymous Call Rejection (ACR). Under the Telecommunications Data Protection Directive (97/66/EC) customers must be given the ability to reject calls where callers deliberately withhold their number. This requirement will be incorporated into UK law on 1 March this year. From that date network operators will have to offer an ACR service whereby a customer can choose not to receive calls where the caller has withheld CLI.

1.5 As a result, where callers on large private networks withhold their CLI for perfectly legitimate reasons – to avoid presenting the customer with a misleading CLI number – they will not be able to get through to the customer. In some cases this inability to connect could have serious consequences – eg a call from an area health authority or from the police service.

Proposals

1.6 The consultation paper proposed a way of overcoming these difficulties, by a more widespread use of presentation numbers. A presentation number is a diallable number to which a return call may be made. However it does not directly identify the line from which a call originates. It could, for example, be a non-geographic number such as a Freephone (0800) or personal number although it must never direct callers to a premium rate service number. Diallable in this context means that not only has the number been allocated to an actual subscriber but that it is in use, connected to a terminal and capable of receiving calls.

1.7 Under the existing rules Oftel only allows presentation numbers where they are inserted by the network or can be directly checked by the network. In both cases the number is described as having been verified by the network. However numbers that are inserted by the caller's equipment and delivered to the network cannot be verified in the same way. These numbers are described as type 3 presentation numbers. A fuller description of the types of presentation number is included in Annex F.

1.8 Oftel now proposes that the rules preventing the use of type 3 presentation numbers should be lifted, subject to adequate safeguards being in place. A number of benefits flow from this move. Callers will be put in the position of being able to send a meaningful CLI. The use of a presentation number, as an alternative to withholding CLI, would also avert the risk of having their calls rejected by ACR. There would also be a gain for customers who would receive useful CLI information about a call rather no information, or – in some circumstances – no call at all.

1.9 However because type 3 presentation numbers are not verified by the network their use in the UK breaks new ground. It is important to balance the introduction of this service with an appropriate level of safeguard measures. It is vital that the CLI customers receive is authentic. Where networks cannot verify CLI information other forms of verification become essential. For this reason a significant element of the consultation was to consider the range of possible safeguards and invite comments on which of them would help maintain and promote public confidence in CLI services.

1.10 The rest of this Statement reviews the responses made to the questions raised in the original consultation – should type 3 presentation numbers be allowed and if so what safeguards are needed. It explains how Oftel proposes to carry the matter forward. Chapter 2 deals with the broad question of whether type 3 presentation numbers should be allowed at all. Chapter 3 considers the safeguards Oftel proposes to put in place and Chapter 4 the contractual obligations (Special Arrangements) those subscribers allowed to use type 3 presentation numbers will be required to enter into.

Chapter 2

Type 3 presentation numbers

2.1 The first question the consultation paper raised was:

Would customers, on balance, benefit if the use of type 3 presentation numbers, subject to sufficient safeguards, were to be permitted?

2.2 This was the most fundamental question of all. It turns on a judgement as to whether the advantages that accrue to customers in receiving useful CLI information about incoming calls outweighs any possible lessening of the authenticity of CLI numbers.

2.3 Most responses to the consultation took a balanced view, recognising the benefits but also mindful of the need for adequate safeguards. There was a strongly held view that the ability to use type 3 presentation numbers should not be made freely available but restricted to certain categories of users who had a genuine need for use of non-verified CLI (see Annex B, paragraphs B1 – B5, for a fuller analysis of responses).

Oftel has now concluded that there is a strong case for allowing type 3 presentation numbers to be used by companies and that their availability will benefit business and residential users.

2.4 From the standpoint of companies and other organisations with extensive private networks there is a considerable advantage in being able to offer called parties a meaningful CLI number rather than withholding their CLI, as many are forced to do at present. Not only does this promote transparency and avoid the dislike that many customers have for anonymous calls. An additional advantage is the ability to connect calls that would otherwise be rejected by anonymous call rejection.

2.5 However it is wrong to see type 3 presentation numbers as no more than a device to enable corporate users to overcome ACR mechanisms. Oftel firmly believes that they are genuinely useful for residential users. For users subscribing to an ACR service the benefit is very clear. They will receive calls, some of which may be vital, that would have been rejected otherwise. But even where ACR is not an issue it is clearly preferable to receive a call identified by a meaningful CLI rather than being anonymous.

2.6 This conclusion is consistent with Oftel’s long-term support for CLI services. These redress the balance of knowledge between calling and called parties and give users more control over their telephone by being able to identify who is calling or has called them.

Chapter 3

Safeguards

3.1 Arguably the most significant part of the consultation was that which dealt with the range of safeguards that it will be necessary to set in place so that customers continue to have confidence in the authenticity of CLI information. Not surprisingly, it was this issue in which respondents showed the greatest level of interest and which provoked the widest range of responses (see Annex B, paragraphs B11 – B12). The question raised by the consultation was:

Which safeguards are desirable or essential to maintain customer confidence in the authenticity of CLI information?

Exhaustive checks on applications for special arrangements

3.2 The first safeguard the consultation document proposed was that network operators should make thorough checks of each individual application for a special arrangements contract for type 3 presentation numbers. The responses revealed a striking consensus between network operators and consumer groups, although for conflicting reasons. Several network operators thought they were not qualified to exercise what is effectively a regulatory function. Consumer groups, on the other hand, thought that Oftel involvement in this process would generate a higher level of consumer confidence.

3.3 Accordingly Oftel proposes to play an active part in determining which organisations should be allowed to use type 3 presentation numbers. As well as drawing up the criteria against which applications will be considered Oftel will have the final say in their acceptance or rejection. The application process will require calling companies wanting to use type 3 presentation numbers to answer a series of questions indicated by Oftel. Replies will be submitted to network operators which will consider each application and make an initial recommendation to Oftel on the suitability of a particular application.

3.4 However the final decision as to whether a particular applicant is allowed to use type 3 presentation numbers will remain with Oftel. This decision will be based on a number of factors: the legal nature of the entity applying (individual subscribers are excluded), whether their network incorporates least-cost routing and multiple break-out, and the benefits accruing to customers of receiving calls which would otherwise not been connected. Detailed procedures for processing applications – both for Oftel and network operators – will be drawn up within the CLI Interest Group, an industry body where operators, equipment suppliers and users are represented.

3.5 It is indicative of how seriously Oftel takes the issues of authenticity and customer confidence that it is prepared to undertake this level of initial direct involvement. Although the general aim of policy is to withdraw from detailed regulation of the industry as competition develops, Oftel considers that in this case customers’ data protection and privacy rights cannot be ensured without some regulatory intervention, at least to start with. The effectiveness of these arrangements and the appropriate level of future involvement will be reviewed once sufficient experience has been accumulated – say, after the proposed arrangements have been running for at least 18 months.

Who can use type 3 presentation numbers?

3.6 The consultation document emphasised that the proposed special arrangements would not be available to all applicants but only to those who had a demonstrable need for them. Oftel now makes the following specific proposals:

• applications for special arrangements will only be accepted from companies or other private or public bodies – individual users are categorically excluded;

• the applicant will need to have a private network operating over a number of discrete sites;

• the applicant’s private network will have to incorporate least-cost routing and multiple break-out as a network feature;

• the applicant will be required to demonstrate that there are potential disadvantages to customers from its use of either types 1 or 2 presentation numbers, which are either wholly or in part checked by the network, and that it has reasonable grounds for withholding CLI;

• the applicant will be required to show that a failure to connect its outgoing calls is detrimental to the interests of consumers;

• the applicant will be required to show that there is no alternative solution.

3.7 These criteria will be used as the basis for the questions subscribers will have to answer if they wish to apply to use type 3 presentation numbers (see Annex C for an indicative set of questions).

Technical safeguards

3.8 The consultation also looked at the possibility of requiring safeguards that rely on the technical capacities of networks. One was that there should be some way of letting called parties know, either by text message or spoken network announcement, that the CLI number displayed was a type 3 presentation number.

3.9 Oftel has concluded that it would not be practicable to require the implementation of this feature across all networks before type 3 presentation numbers can be made available. However we believe that an indication of the status of a CLI number is desirable and we will encourage operators to deploy this feature when upgrading their networks. The CLI Interest Group will be asked to study technical issues arising from its implementation and appropriate timescales for its deployment.

3.10 Another safeguard the consultation considered was that terminating networks might be required to deploy call-logging systems to log the details of type 3 presentation numbers where there was evidence or suspicion of abuse. Because these systems are not universally present in the installed base, it would not be appropriate to postpone the availability of type 3 presentation numbers until the necessary upgrades had been implemented. However, even where call-logging systems have not been deployed in the local network, modern networks have extremely sophisticated call-tracing technologies used for malicious call identification and other law enforcement purposes so the capacity to track down the abusive use of type three presentation numbers is already available.

A new class licence condition

3.11 Oftel also intends to modify the class licences under which the calling parties concerned run their systems by introducing a new condition requiring a licensee only to use authentic calling numbers as presentation numbers. This will give Oftel a direct enforcement role where presentation numbers are used and supplements the legal constraints on the abuse of presentation numbers provided by section 43 of the Telecommunications Act 1984 and the enhanced powers the Data Protection Commissioner will have when the Data Protection Act 1998 is fully implemented. The licence condition that Oftel proposes to include in the class licences is at Annex E.

Chapter 4

Special arrangements

4.1 The consultation also considered what kind of contractual arrangements subscribers allowed to use type 3 presentation numbers should enter into. A draft agreement – the Special Arrangements agreement – was included at Annex 3 in the consultative document. The question asked in the consultation was:

How effective is the draft Special Arrangements agreement and how might it be improved to maintain customer confidence in the authenticity of the CLIs presented?

4.2 The Special Arrangements agreement is a contract between a calling party and a network operator. In return for being allowed to use type 3 presentation numbers the calling party enters into an undertaking only to supply authentic calling numbers. The idea of a Special Arrangement was originally developed by the European Telecommunications Standards Institution (ETSI), a body working on the technical specification of CLI services, as an alternative to network verification.

4.3 The possibility of relying on Special Arrangements has already been recognised by the Code of practice for network operators in relation to customer line identification display services and other related services. The Code of practice was developed by an industry group of network operators and equipment manufacturers to promote the consistent handling of CLI information transferred across competing networks.

4.4 To take account of responses to the consultation (see Annex B, paragraphs B6 – B10) the wording of the contract will be modified in the following ways to introduce extra checks and safeguards.

• Subscribers will be required to nominate the numbers they intend to use as presentation numbers and to inform network operators of any changes in the allocation of these numbers. Network operators will maintain lists of these nominated numbers which will be open to Oftel scrutiny;

• Subscribers will be required to take responsibility for the correct configuration of their equipment so that it is able to convert a private network address to a valid CLI number in public form;

• Because a contract provides for more certainty where it does not refer to an external document the exclusion of premium rate numbers will be based on the Numbering Conventions rather than on the ICSTIS list of Premium Rate Dialling Codes. All premium rate services are migrating to numbers that will sit behind an 090 or 091 prefix;

• Oftel also proposes to relax the existing rule that a presentation number has to be allocated to the same legal entity as the corresponding network number. However a subscriber wishing to use a presentation number allocated to a separate legal entity will be required to obtain the written consent of that legal entity to its use for display purposes.

4.5 On the latter point there is evidence that the existing rule has inhibited some network operators from offering presentation number services because of the complexity of Companies Act legislation which determines whether two companies are legally comprised in a single entity. There are also perfectly legitimate uses of presentation numbers that this rule prevents (eg a number translation service being able to pass on an originating caller’s network number as a presentation number).

4.6 The amended Special Arrangements agreement is given in Annex D.

Annex A

Respondents

Advisory Committees on Telecommunications

Consumer Communications for England (CCE)

Northern Ireland ACT (NIACT)

Scottish ACT (SACOT)

Welsh ACT (WACT)

Disabled and Elderly people (DIEL)

Network Operators

British Telecom

BT Cellnet

Colt

Energis

NTL

Orange

Scottish Telecom

Telewest

Vodafone

Equipment Suppliers

Nortel

Siemens

Trade Organisations

Federation of the Electronics Industry (FEI)

Federation of Small Business (FSB)

Telecommunications Managers Association (TMA)

Corporate Users

Association of Social and Community Alarms Providers (ASAP)

British Broadcasting Corporation (BBC)

Central Computer and Telecommunications Agency (CCTA)

Individual Users

David Bickell

Henryk S Matysiak

Andrew Taylor

Annex B

Responses

Question 1

B1 The first question posed by the consultation document was whether

customers would, on balance, benefit if the use of type 3 presentation numbers, subject to sufficient safeguards, were to be permitted?

B2 This question evoked a generally cautious response. There was a recognition that the introduction of type 3 presentation numbers would produce consumer benefits but also an awareness that without adequate safeguards public confidence in the reliability of CLI information could be placed at risk.

B3 The most common response was that type 3 presentation numbers could be made available but only in a limited set of circumstances. Primarily it should be restricted to corporate users within the far-end breakout scenario. The requirements of a particular user for this type of presentation numbers should be closely examined and should only be permitted where it can be demonstrated that there are no alternative solutions based on type 1 or 2 presentation numbers.

B4 There was no support at all for making type 3 generally available – say to single line ISDN residential users.

B5 Consumer groups were generally more concerned about the potential loss of public confidence in CLI than any other group of respondents but even network operators recognised that a measured and cautious approach was required.

Question 2

B6 The second question was about the effectiveness of the draft Special Arrangements agreement and how it might be improved to maintain customer confidence in the authenticity of the CLI numbers presented?

B7 The draft Special Arrangements agreement was generally welcomed although there was a view that the penalties for non-compliance with its terms should be more explicitly described.

B8 One operator made the case for an additional section obliging the subscriber to notify the network operator of any changes to number allocations where those numbers were in use as presentation numbers.

B9 One respondent thought that the agreement should recognise a role for equipment suppliers in making sure that subscribers should be informed as to how their equipment should be configured to translate numbers from a private network numbering plan to a valid CLI number.

B10 Reaction was mixed to the proposal that, provided consent was obtained, the requirement that linked presentation numbers and network numbers be allocated to the same person or legal entity, should be relaxed.

Question 3

B11 The third question was about which safeguards are desirable or essential to maintain customer confidence in the authenticity of CLI information.

B12 The safeguards prompted most discussion and the widest set of reactions. Most network operators tended to the view that the proposals were too onerous and that contractual arrangements backed up by existing legal constraints and new class licence obligations should suffice. The counter view was that the full range of proposed safeguards should be adopted but that in addition one or two needed strengthening. To take the individual proposals in turn:

Annex C

Indicative questions

Q1(a) What is the name and nature of the applicant’s business? Please give the address of its Registered Office and its Company Registration Number.

or

Q1(b) If the applicant is not an incorporated company what is its name and the nature of its activities? What is the address of its head or main office and charity registration number if applicable.

Q2 Describe the architecture of the applicant’s telecommunications network, including the number of switches and separate sites, its spatial extension and extensions served.

Q3 Are least-cost routing and multiple breakout features implemented in the applicant’s network?

Q4 If so, approximately how many outgoing calls are made over these network features are made in an average week?

Q5 What is the applicant’s current practice on the display of outgoing CLI?

Q6 What, if any problems, have been encountered in the exercise of the applicant’s current CLI practice?

Q7 Does the applicant currently use either type 1 or type 2 presentation numbers on outgoing calls?

Q8 What, if any disadvantages, has the applicant encountered in its use of type 1 or 2 presentation numbers?

Q9 Assess how an inability to connect outgoing calls would act to the public detriment?

Q10 Give a reasoned explanation of why the applicant should be allowed to deploy type 3 presentation numbers and why no alternative solution is viable.

Q11 Indicate the numbers that the applicant wishes to use as type 3 presentation numbers. Evidence will be required that the numbers have either been allocated to the applicant or that the applicant has written consent for their use as presentation numbers from persons who can supply evidence that the numbers have been allocated for their use.

Q12 Supply the name, official title and contact details of an individual who will carry responsibility for the implementation and exercise of the organisation’s CLI practices.

Annex D

A Special Arrangements contract

1. The subscriber hereby undertakes to the network provider that any number provided for display will be:

2. The subscriber will:

3. By entering into this contract the subscriber confirms that he has taken appropriate technical advice that the equipment comprised in his/her system has been correctly configured to convert a private network address to a valid CLI in public form.

4. In entering into this agreement the subscriber recognises that any failure on his or her part to fully comply with its terms may lead to the network provider withdrawing the special arrangement without further notice and irrespective of any contrary contractual obligations.

Annex E

Proposed class licence condition

Calling Line Identification

Where Apparatus comprised in the Applicable Systems is capable of forwarding a Number to a public telecommunication system by means of which the Network Termination Point of the Licensee's system may be identified the Licensee shall ensure that any such Number forwarded for identification and display purposes is:

Annex F

Types of presentation number

F1 Three types of presentation number are identified in the Code of practice for network operators in relation to customer line identification display services and other related services. Although this Statement is primarily concerned with type 3 presentation numbers it will be helpful to describe all three types.

F2 Presentation numbers can be categorised on the basis of whether they are network or user provided; in other words is the CLI number applied at local exchange level by a network operator or is it delivered along access lines by the caller's own equipment. Where the CLI comes from will have a bearing on the degree of verification, or network testing, it will be subject to.

F3 The three types are:

type 1 – network provided (NP)

• a network provided presentation number which is stored in the network and applied to an outgoing call at the local exchange by the network operator;

• because the number is applied by network equipment there is no need for it to be verified each time a call is made – instead the level of authenticity will depend on the checks made by a network operator before a subscriber is allowed to use a particular presentation number;

type 2 – user provided, verified and passed (UPVP)

• a user provided number is not applied at the local exchange but is forwarded by the user's own equipment;

• type 2 presentation numbers typically identify a caller’s extension number behind a digital, Direct Dialling In (DDI), switchboard;

• although the number is provided by a user's swithchboard the network operator can check that it falls within the range and length allocated to a particular subscriber – in this way the authenticity of the CLI is maintained;

type 3 – user provided, not verified (UPNV)

• in common with type 2 presentation numbers, these are forwarded by a user's equipment – the difference is that network checking procedures are replaced by a special arrangement between the subscriber and the network operator in which the subscriber undertakes only to provide an authentic calling party number.

Glossary of terms

Anonymous call rejection – a service which prevents calls from being connected or put through where a caller has withheld CLI

Caller display – on fixed lines a subscription service (but generally free on digital mobile networks) which displays the number from which a call has been made – it requires a caller display unit with a screen, either on the telephone or as a separate attachment

Calling line identification – a network facility that enables the number of the line from which a call is made to be identified

Direct Dialling In (DDI) – a switchboard’s capability to route an incoming call to the extension dialled without the intervention of an operator

Far-end breakout – a feature of private networks that routes a call made to a public network number to breakout on to a public network as close to that number’s line as possible

Network number (NN) – a number allocated by a telephone company which identifies the line from which a call has been made, usually the same as the directory number

Network Provided (NP) number – a number stored in the network and applied as the CLI of an outgoing call – it can be either a network or a presentation number

Originating network – the network to which a caller who makes a call is directly connected

Presentation number – a number chosen by a caller to which return calls may be made

Special arrangement – an agreement between a subscriber and a public network operator whereby the subscriber undertakes to provide for CLI display purposes only authentic calling party numbers which are not checked by the public network

TDPD (the Telecoms Data Protection Directive) – European Parliament And Council Directive of 15 December 1997 concerning the processing of personal data and the protection of privacy in the telecommunications sector (97/66/EC). A Directive that applies the general principles of the Data Protection Directive within the field of telecommunications

Terminating network – the network to which a customer who receives a call is directly connected.

Transit network – a network through which a call passes, but which is neither the originating network nor the terminating network for that call.

UPNV (User Provided, Not Verified) number – a number that is supplied by a user which identifies a NTP and has not been subjected to screening or editing by the network.

UPVP (User Provided, Verified and Passed) number – a number whose most significant part is network provided and whose least significant part is supplied by a user and successfully checked by the network for length and range

Withheld – where a caller has chosen not to allow a CLI to be presented to the person being called