1Telephone numbers belong to people and businesses and they need to be treated as a national resource. Oftel took over responsibility for the UK Numbering Scheme from BT in 1994. This means that Oftel now makes plans for the future use of numbers and allocates numbers to telephone companies to allow them to provide service to their customers. To help us make the right decisions, we are committed to consulting all those with an interest - residential customers, business users and the telecommunications industry.
2 All area codes changed on 16 April 1995. This change to the Numbering Scheme offers many new opportunities for the development of services. But we want to make sure numbers are used in a way that best meets customers' needs.
3 This booklet is about 'geographic' or 'fixed' telephone numbers: the ordinary phone numbers we are familiar with at home and at work.
4 There are two typical patterns for geographic telephone numbers in the UK. Large cities (like London, Bristol and Edinburgh) have short area codes and long local numbers. The code and number are made up of digits. Every area code has an 0 in front of it. This is known as the national dialling prefix: it tells the telephone network that this is a nationally-dialled, and not a locally-dialled, call.
5 Smaller cities, towns and rural areas (like Cardiff, Elgin and Sandy) have longer area codes and shorter local numbers.
6 When you call someone in another area code you must dial the prefix 0, the area code and the local number - this is known as full national dialling.
7 When you call a person with the same area code, you usually dial only their local number - this is known as local dialling. But you can dial the full national number if you prefer. Your call will be connected and the charge is the same either way.
8 Telephone numbers are used by the telephone companies to decide how calls should be sent through their networks and to set the charge for the call.
9 People often use the area code to work out how much they can expect to pay for the call and to identify the place they are calling. It may be particularly useful in some cases to identify numbers for services in the local area, such as plumbers and electricians
10 Businesses often use numbers in their telephone equipment to work out the most efficient way of routing calls (for example looking at the code to decide whether it would be cheaper to send by Mercury or BT).
11 The UK has one of the most dynamic tele-communications markets in the world. Over 150 telephone companies are now competing to offer new products and services which customers want. All these companies need numbers.
12 Much of the recent growth has been for special services (such as freephone and premium-rate) and mobile services. This trend is expected to continue.
13 The arrival soon of new Personal Numbering services will also increase demand for numbers. Numbers for these services - known as 'numbers for life' - identify you rather than your phone. Calls are able to reach you wherever you choose, using the same number: whether you are at home, in the office, on the move using a mobile phone or even in your holiday hotel.
14 Developments in technology mean that in future many of our day-to-day services such as entertainment, banking, shopping, education and information will be available over telephone networks to your home, place of work, schools or libraries. These new services will all need numbers.
15 In addition to this growth in brand new services, there continues to be a heavy demand for 'number hungry' geographic services which currently use 01 numbers. Most of this demand is coming from the workplace. Businesses who used to have just one phone number, with all calls routed through a switchboard, are now putting in individual numbers for each extension so that people working there can be called directly (Direct Dialling In). This can increase a company's needs from one or two numbers to hundreds or thousands. Even small businesses usually have at least two numbers - one for phone and one for fax.
16 People at home are also likely to be using new services which need more numbers. Faxes at home and computers with modems linking them to the phone network are becoming more common. Also, some telephone companies now offer different ringing (and a different number) for each member of a household. This allows you to recognise whether an incoming call is for you by the sound of the ringing. If this service becomes popular, an average household's demand for numbers will rise.
17 A major step towards meeting this demand for new numbers was the National Code Change. Since 16 April 1995 (PhONEday), all geographic numbers have area codes which begin 01. The change separated codes beginning 02 to 09 for other uses and created a total of eight thousand million (8 000 000 000) new numbers behind these other codes.
18 This extra capacity will allow UK customers to enjoy access to many new services and will minimise the need for future number changes. It also gives us an opportunity to use numbers in a more meaningful way: so you can tell easily from the first few digits the type of service you are calling and, to some extent, the likely cost.
19 Under this new Numbering Scheme numbers beginning 04 can in future be used for mobile services; 07 for Personal Numbering services; and 08 for special services such as freephone, services charging national calls at local rate and some information services.
20 Using 04, 07 and 08 in this way will provide an extra 3 000 million numbers for mobile, personal numbering and special services while 03, 05, 06 and 09 will remain in reserve for future use by new services.
21 We will be consulting further in the future on:
22 But what about the pressures for more fixed geographic numbers? Numbers beginning 02 have been set aside to give additional geographic capacity. But no decisions have been taken on how 02 numbers should be used.
23 The present geographic scheme - now using 01 numbers - was designed by the Post Office in the 1950s and is based around 638 areas, each of which has a code. With the exception of London and some other major cities, all these areas are of similar size. This means that the same quantity of numbers - in theory 800 000 numbers - is available in rural areas (eg Bodmin 01208) as in some urban areas (eg Bolton 01204). The Appendix explains the history of geographic numbers in more detail.
24 Only about half of the numbers behind each area code are in fact used (around 400 000). This is because of technical factors and potential demand for particular groups of numbers (see the Appendix for more details).
25 The effect of this poor usage of numbers and standard area size is that, although there are around 650 million potential numbers, only a small proportion of these are actually used. Most codes have relatively few numbers in use and will never run out. But some other codes, mainly in urban areas, may need more numbers to satisfy growing customer demand. Some current estimates indicate that of the total of 638 up to seven code areas - Belfast, Cardiff, Inner London, Outer London, Portsmouth, Reading and Southampton - may need more local numbers over the next five years.
26 These estimates represent a worst case picture. It is important to realise that more rigorous management of the numbering resource by Oftel, combined with the opening up of new ranges and the introduction of number portability (where you can keep your number if you change telephone companies), are likely to reduce the demand for new 01 numbers.
27 The rest of this booklet sets out a strategy to make more geographic numbers available. Using new 02 numbers gives some exciting opportunities. And there are also ways of making sure we always have more 01 numbers available in any areas that might need them. We are looking for your views on our strategy
28 In putting together our ideas in this booklet we have tried to take account of the things about telephone numbers and changes to numbers that are important to people.
29 There used to be a close link between distance and charging. People have grown to expect that when they dial a number with the same area code as theirs, they are charged at the 'local rate'.
30 This is becoming less important because:
31 There is little information on the importance of local dialling. We know that, while businesses often make a lot of national calls, residential customers have traditionally dialled mostly local calls.
32 This pattern is starting to change as national calls get cheaper and special services (for example freephone) grow in popularity. Also, calls to mobile phones use national dialling. More and more people are finding they dial longer numbers as a routine part of their phone use.
33 Oftel is commissioning market research to find out more about people's views on the use and importance of local dialling and the significance of area codes. The results will be available this summer and, together with the responses to this document, will help with future decision-making on geographic numbers.
34 Nobody wants unnecessary changes to codes or to numbers. But we need to remember that gradual change and evolution have always been a feature of numbering in the UK, and indeed elsewhere. The modernisation of telephone exchanges and other developments have meant the need for some changes for some people. The important thing is to plan carefully so changes are kept to a minimum.
35 When changes need to happen, they can be made easier for everyone by changed number announcements which remind you about a change if you dial the old number after the change has been made.
36 An additional feature of the National Code Change was the nine-month period of parallel running before PhONEday when you could use either the old number or the new 01 number. This gave businesses the chance to reprogram equipment, reprint stationery and change adverts at a time that suited them.
37 Oftel is committed to the introduction of number portability. This will allow you to keep your old telephone number if you decide to change your local telephone company. This should lead to the more efficient use of numbers by telephone companies and delay the time when more numbers need to be made available.
38 The National Code Change increased the maximum number length in the UK to the national dialling prefix 0 plus ten digits - the same as the US and Germany. Although international rules will allow numbers to increase by another three digits in January 1997, Oftel does not intend to make people change to longer numbers. The eight thousand million extra numbers created by this year's change will give the UK plenty of numbers for the foreseeable future.
39 Oftel believes there are two different approaches in which the future demand for geographic numbers could be met. These are:
Under this approach, the demand for geographic numbers would continue to be met for the foreseeable future by using 01 numbers. 02 would be kept in reserve until it is needed.
Under this approach, 02 numbers would be used at an early stage to introduce a new geographic scheme across the UK which would provide an alternative to 01 numbers. Existing 01 numbers would not change and new 01 numbers would be available for those who want them. There would still be a need to 'make 01 stretch' but to a much lesser extent than if 02 were not used.
These two approaches are described in more detail in the following pages, looking first at the possibilities for the new 02 range.
40 There is a third approach available. This would involve introducing 02 codes only in the few areas that might otherwise run out of 01 numbers. Although this might seem attractive at first sight, we think it may well not be the best solution. This is because:
For these reasons Oftel proposes not to use this third approach. Do you agree with our proposal?
41 If we could plan a geographic scheme for the UK from scratch, we would be unlikely to produce the areas now in use in the 01 codes. They cover small areas and do not reflect the size of population. The availability of 02 under the new Numbering Scheme provides an opportunity to create a coherent, flexible structure which better reflects customer demands and which will make new tariffs covering wider areas easier to understand. Eight hundred million new 02 numbers would be available.
42 Under this approach, the UK would be divided up into areas large enough to reflect population demand but small enough to give geographic meaning. The 02 codes would be 'laid on top' of the 01 codes. In other words, both an 01 and 02 code would be available in each area.
43 There would be a choice between 01 and 02. The 02 numbers would cover wider areas than 01 numbers. It would still be possible to tell what a call costs from its 02 code; but the 02 tariff may be different from the 01 tariff. Businesses which have offices across a region could benefit from having numbers within the same 02 code. Also, 02 numbers could be portable across the wide area, helping people who move house or businesses outside a town but within the same region.
44 If we are to avoid the inefficiencies of the 01 codes, 02 will need to follow a different pattern. The new 02 codes will need to reflect demand more accurately by taking account of population density, level of economic activity and growth trends. It will also be important to make sure that the 02 codes cover a geographic area that is understandable to users.
45 Using 02 numbers offers some important new opportunities. First, unlike 01 codes, it would be possible with a new scheme to be flexible about the boundaries between codes. So if, for example, there was a new 02 code for the Midlands and one for East Anglia, someone living on the boundary of these two regional areas could opt for either code.
46 Second, because 02 codes would generally cover larger areas, fewer 02 area codes would be needed and codes could be shorter. If, for example, the UK were to be covered by ten or fewer 02 codes then each code would only need to be 0 plus two digits long ( 021, 022 and so on). It would also greatly increase the amount of local numbers available: with a 0 plus two-digit code there would be 8-digit locally-dialled numbers which would provide eighty million numbers in each area (compared with eight million within the 0171 London area). To give greater geographic meaning, some of the codes could be expanded to 0 plus three digits (0211, 0220 and so on) which would be similar to the short area codes used in the United States and France.
47 Third, the UK would be able to break free of the old 'Post Office' numbering and charging structure. Telephone companies would be freer to introduce innovative charges at competitive rates, for business and residential users. More people would benefit from greater choice.
48 One possible drawback would be the existence of two types of geographic number in an area. If you had an 02 number and you wanted to ring a friend nearby who also had an 02 number, you would just dial the local number. If you wanted to ring another local friend who had an 01 number you would have to dial the full national number. However, as time goes by, people with 02 numbers would be able to dial local numbers to more people over a wider area than those with 01 numbers.
49 We propose that the following guiding principles be followed in setting up a new 02 geographic structure for the UK.
50 Oftel believes that many customers would welcome the opportunities available from the introduction of this sort of scheme. Others who preferred 01 numbers would be free to continue with them - no one would have to change unless they chose to. The availability of 02 numbers would reduce demand for 01 numbers and postpone the date at which more 01 numbers might be needed. However, action to make more 01 numbers available in a few of the areas under pressure would still need to be taken. We would propose to follow the approach explained in the next Section Making 01 Stretch.
Q Do you agree that 02 should be used now for a new geographic numbering structure?
If so, do you agree with the principles set out in paragraph 49? In particular let us have your views on using ten or fewer short 02 area codes - and on the possible boundaries for those areas.
51 Oftel wants to make sure that people can still have 01 numbers if they choose. As we discussed in paragraph 25, most 01 codes have relatively few numbers in use and will never run out. But there may be a few places - more if we do not make use of 02 - where we will need ways of providing additional 01 numbers. We want to do this in a way that causes as little disruption as possible
52 There is enough scope to use 01 codes for a long time. Because of PhONEday, sixty 01 area codes are now free and over two hundred more codes will become free over the next two years. And it is possible to make more efficient use of the 01 numbers already available.
53 We propose to follow a step-by-step approach when more numbers are needed in an area. This approach will make sure that we first take actions that cause least disruption to customers. We would take one step at a time as and when necessary.
54 Our first step would be to make sure that numbers are managed efficiently by the telephone companies. The Appendix at the end of the booklet explains that only about 40% of the available numbers are generally used. Our aim here would be to introduce measures to encourage the use of as many of the numbers available in a code area as possible before any other change is considered. We would only introduce these measures in areas where potential shortages had been identified.
55 This means making sure that telephone companies make more efficient use of the numbers they already have before more numbers are given to them. In areas of potential 01 shortages, the telephone companies would be expected to use at least 60% of the numbers allocated to them. In particular we would expect them to:
56 Oftel would not normally expect to allocate more numbers to telephone companies who do not follow the conservation measures described above in areas of shortage. Oftel would not allocate blocks of 01 numbers to telephone companies for non-geographic services such as paging, mobile and personal numbering services. Oftel would also take appropriate action to move existing services from 01 numbers to 04 or 07. In addition, where it is appropriate, the take up of numbers in other number ranges would be encouraged.
Q What are your views on these conservation measures? Can you suggest others?
57 Where these conservation measures are not able to provide enough numbers to satisfy demand, we would look at the practicalities of making the code for the area shorter and the local number longer.
58 Here the full national number would stay the same but the digit at the end of the code would move to become the first digit of the local number. In the example below, the code would change from 01447 to 0144 with the 7 becoming the first digit of the local number. National calls to the area would be unchanged but if you lived there and wanted to make a local call you would need to add 7 in front of the number.
59 Disruption is limited because there is no apparent code change for people dialling in from outside (using the full national number). But parallel running and changed number announcements might be difficult in some instances. This change would provide about three hundred thousand more numbers in any local area. In the example, seven-digit local numbers beginning 70, 71 and 79 could now be used; these were unavailable before as six-digit numbers because local numbers beginning with 0, 1 or 9 cannot be used - as explained in the Appendix. All local numbers would begin with the same digit (7 in the example). Different digits (eg 3 in the example) cannot normally be used because adjacent codes (eg 01443 in the example) may not be free.
60 At a later date, a second 01 code could be introduced if more numbers were needed. The code would provide another million numbers for the area. In the example below, the additional code 0199 6 is used. Local dialling between the codes would be available for all customers because old numbers would begin with one digit and new numbers with a different digit - in the example 6 and 8.
61 Step 2 will not always be feasible, so then we would consider a new code for the area. This involves changing to a shorter area code and extending the local number. This is the way 01 number shortages have mostly been dealt with up to now. On PhONEday five cities - Bristol, Leeds, Leicester, Nottingham and Sheffield - changed this way. In the example below, the code changes to 0118 with a 9 added to local numbers.
62 This increases available numbers in an area from eight hundred thousand to eight million. It is fairly easy to understand and it maintains local dialling and the charging arrangements for local calls. All telephone companies and their customers are treated equally.
63 However, because it involves a code change it is disruptive - particularly for businesses. Cost and inconvenience can be reduced by having long periods of parallel running before the change, and number announcements afterwards.
64 Sometimes it may be possible to consider creating more numbers by dividing a code into two. This option would use a new 01 code for half the people in the area; local numbers would stay the same. In the case of two numbers in the example below (01596 222 000 and 01596 777 000), one would stay 01596 222 000 while the other would change to 01739 777 000.
65 This doubles the available numbers and only half of any community needs to make a change. But it risks some customer confusion and misdialling. Also, it is not usually easy to make a simple division within the old code area. We would only consider it in an area which has two clearly distinct communities.
Q We have proposed a step by step approach, ranked so that the options which were least disruptive to customers come first. Do you agree with the steps we have proposed and the order we have put them in? Are there any other steps - ways of creating more local 01 numbers - which we should consider?
66 It is clear that there will continue to be a demand from customers for 01 numbers into the foreseeable future. In the vast majority of cases this demand can be met within the existing arrangements. However we recognise that up to seven code areas may run out of numbers over the next five years unless action is taken now.
67 We believe that the use of 02 for a new national scheme would divert demand away from 01 numbers. We would also use conservation measures to make sure that telephone companies make best use of the numbers available. The introduction of number portability - keeping your number when you switch between operators - will help increase number efficiency. Only when these factors had been fully exploited would we move on to the additional measures described in paragraphs 57 to 65.
68 It is important that all those with an interest in telephone numbers - residential customers, business users and the telecommunications industry - let us have their views. The deadline for comment is 25 August 1995 and ways of responding are shown on the inside front cover. Once we have considered all the responses, and taken account of relevant market research, we intend to publish policy proposals in the autumn.
In the early days, before phones became commonplace, it was sufficient to have a few thousand numbers associated with a place name to identify an area. Whitehall 1212 was a well known example. Local numbers could be reused in other geographic areas providing a different place name was used.
When automation allowed callers to make trunk calls between different areas without the help of a human operator, it became necessary to simulate the place names by groups of digits, now known as area codes. Further development of telecommunications systems allowed callers to make international calls using a few digits to identify a country, followed by an area code and then the local number.
Although introduced primarily to allow callers to identify the party being called, numbers were found to have other uses. Telecommunications systems can examine a number of digits to work out how a call is to be routed through various switching centres. Where the charge for a call varies with the distance, area codes can be used in price lists to show the tariff for a call from one area to another.
When trunk service was first automated in the UK in the form of Subscriber Trunk Dialling (STD), existing place names for the geographic areas were abbreviated into meaningful letter/figure combinations to create a relatively friendly user-to-network interface. For example, Cambridge was given the code CA3 and the code LE2 was allocated to Leeds. However, because telecommunications systems recognised only the equivalent numerical information Cambridge was processed as the code 223 and Leeds as 532.
However, this policy of using letter/figure combinations proved to be very short sighted a few years later when International Direct Dialling became available, because there was not an international standard for the association between letters and numbers on dials and keypads. Many foreign countries do not use the English alphabet at all, and those that do have various other number/letter associations. The UK therefore moved to All Figure Numbering (AFN) The consequences of this course of events can be seen in the haphazard structure of codes in the UK Numbering Scheme.
For most areas with 01 numbers a four-digit code is followed by a six-digit local number, making ten digits in all. For example the code for Reading is 1734 followed by six-digit local numbers. Simple arithmetic suggests one million numbers should be available in each area. But this is not the case, as the table below shows:
Total potential numbers in each 01XXX 1 000 000 100% area code Cannot use local numbers beginning with 0 because 0 is the -10% prefix for national dialling Cannot use local numbers beginning with 1 because 1 is the first digit in a set of short access codes such as 100 (operator) -10% and 192 (directory enquiries) Telephone companies have built their networks using blocks of 10 000 numbers irrespective of demand in any part of an 01 code. These 10 000 number blocks are the 'currency unit' of number management. Also, some numbers in a block may be reserved -20% in case a company direct- dialling-in(DDI) needs extra numbers A block of 100 000 numbers is usually set aside for future expansion from six to seven digit local dialling, using the initial digit of that block (see Step 3 in -10% Making 01 Stretch where 9 has been set aside - paragraph 61) Numbers that have been in use but then become spare are not reused straight away to reduce the risk of unwanted calls; local -10% numbers beginning 99 need to be protected to avoid mistaken calls to the '999' service Numbers available 400 000 40%
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