More on this


http://www.telegraph.co.uk/news/uknews/6702462/Prospect-of-new-telephone-shake-u...

When everything was done by BT, there was a clear and simple system for those places that had migrated to six-figure local numbering (from three and four digit local numbering).


The first two digits of the local NNnnnn number were assigned to one exchange (a block of 10K numbers). If more numbers were needed in that exchange, another 10K block was issued.

You could tell where a number was based by looking at the "N" digits in
(0xxx) NNnnnn
and some exchanges would use several such NNnnnn blocks.

Likewise for Director areas in cities:
(01) NNN nnnn
(0x1) NNN nnnn
the N digits showed the exchange name. A big exchange might have dozens of NNN blocks.

This was in the days before PhONEday.


Then 'cable' arrived, and BT lost control of the numbering process. It was handed to Oftel and then on to Ofcom.

In most places there was only one, occasionally two, cable companies competing with BT.

The cable companies were allocated numbers in 10K blocks, but most chose to cover a wider area than BT with one block of numbers. No longer could you be sure where a number was based.

As the market was opened further, dozens of companies applied for blocks of numbers. Each company was issued with a 10K block of numbers even if they only had a few hundred customers in that area.

So, for the fictitious area (01632) you might have originally had a number of BT exchanges with
- North being 55xxxx and 56xxxx, with a dependent exchange using 51xxxx and 52xxxx;
- East being 61xxxx, 64xxxx, 65xxxx and 67xxxx;
- South being 42xxxx and 46xxxx, with a dependent exchange using 49xxxx, and 40xxxx;
- West being 44xxxx and 45xxxx, with a dependent using 41xxxx; and
- Central being 72xxxx, 73xxxx, 75xxxx and 77xxx, with a dependent using 79xxxx and 70xxxx.

A cable company arrives and is issued 48xxxx, 58xxxx, and 78xxxx which they use anywhere and everywhere within the 01632 area.

Another provider arrives and is allocated 33xxxx, 43xxxx and 53xxxx which they also use across the whole area.

Later, the market is opened up for VoIP and other providers.

Company "A" gets 47xxxx, "B" gets "74xxxx" and so on.

BT needs more capacity in their West exchange but all the 4x blocks are in use. They are allocated 37xxxx for this.

It is getting very hard to tell 'where' within the area, a particular number might be.

More providers arrive and in short order 32xxxx, 33xxxx, 36xxxx, 39xxxx, 54xxxx, 57xxxx, 50xxxx are allocated.

In any area, there are only 79 blocks of 10K numbers available. Those beginning 0x, 1x and 99 cannot be issued.
Those beginning 0x and 1x are allocated as National Dialling Only. They cannot be dialled locally.
Those beginning 99 cannot be issued because of the risk of people ringing 999 by mistake.


A minor company will hold 10 000 numbers even though only a few dozen might be in use. With dozens of companies holding on to one or more blocks in every area of the country, everything is 'allocated' even though very little of it is 'in use'.

That's where it all went wrong. Numbers were previously allocated in 10K blocks per geographical part of a town or city. Nowadays they are issued in 10K blocks per company. This has led to a lot of wastage.

The proposal is to now issue those numbers in blocks of 1000. So for companies only using a few dozen or few hundred numbers in an area, they can immediately return 9000 unused numbers to the pot.

What will happen is that those blocks will be snapped up by yet more companies, and we'll be back to the 'everything allocated, with very little in use' situation within a few years again.

catj wrote on Dec 2^nd, 2009 at 11:00am:

The "conservation" measures, this consultation and any other exercise Ofcom wishes to carry out are necessary because of one thing. That is, the fact that the issuing of numbers in the current manner is totally inefficient. It's not because there is more demand from subscribers (commonly referred to as "consumers") but because of the way in which large blocks of numbers are allocated to providers who only need a few creating unusable wastage.

Telephone numbers are a shared resource and must be managed responsibly. To cut to the chase, continue reading from the "Improving efficiency of number usage" heading below.


This sort of thing really does infuriate me. Putting "conservation measures" in place as a result of the shared resource being used up with threats of having more number changes or an extra code (overlay code) in one particular area is shutting the stable door after the horse has bolted!

And then we have foolish journalists writing stories in national newspapers such as Phone change for London as 020 3 becomes third code.


I'm not too concerned about the loss of the significance of locality of the first few digits within a local number. This still holds good for single BT exchange lines. For others, including those provided in large blocks, for example, for use in offices (i.e. for DDI purposes) there often isn't any significance of where they are within a particular STD area anyway, and this includes those provided by BT.


Improving efficiency of number usage

My thoughts on improving efficiency are that there needs to be a whole new way of allocating numbers. In general terms, I see two types of communications provider with different needs:

1. The main providers such as BT, Virgin Media (ntl:Telewest), Cable & Wireless and so on who operate the bulk of the infrastructure.

2. Smaller providers, typically those operating VoIP services or selling local geographical numbers for redirection.

The first group of providers require many numbers, and in contrast, the second group require very a few.

The large providers need to be able to have allocations of numbers which are consecutive for use with large telephone systems. Those with only a small number of subscribers in an area code should only be given a small number of numbers.


Of course, this all hinges on being able to implement a solution where small providers can have a few numbers, maybe tens or hundreds. What are the technical limitations?

The whole phone numbering system seems archaic to me. There should be one centrally-run database of all the numbers, then they can simply be issued one at a time as they are needed. None of this allocating 10,000 numbers at a time business, which is a hang-over from when numbers referred to a particular exchange. These days, you can port your number from one operator to another, so clearly having an entire block allocated to one provider isn't necessary.

I think the time has come for whole-number dialling anyway. Now mobiles are so ubiquitous, how many people dial numbers with no area code these days? Most regularly-used numbers are saved in a memory somewhere, so rarely actually need to be dialled. This would free up loads of new numbers, as local numbers starting 0 and 1 could be used. This would still allow codes to be used to identify where a number was located. It would also mean companies no longer had "national dialling only" numbers to hide their geographical alternatives to 087/084.

Isn't it funny that we are always hearing stories about the death of the landline, yet landline numbers are running out. That just shows there is serious mismanagement of the numbering system somewhere.

Quote:


The main limitation is the number of digits that need to be dialled before a routing decision is made.

When you dial the first digit, if the digit is 2 to 9 then it is a local number, whereas a 0 says the next digits are going to be an area code, unless the next digit is another zero, then there's going to be a country code instead.

Once you have dialled the area code part of the number, the next two or three or four digits also determine some routing information within that local area.

The digits of a telephone number are referred to (without the zero trunk code) as SABCDEFGHI.
For some small part of London SABCDE is 20 7890 for a number like (020) 7890 nnnn.
For some small part of Birmingham SABCDE is 121  678 for a number like (0121) 678 nnnn.
For some small part of Bedford SABCDE is 1234  77 for a number like (01234) 77nnnn.

In the past, the final routing decision occurs at the E digit. In some SABC area codes already, and in all SABC area codes in the future that decision is going to be made at the F digit level.

That immediately makes the routing database ten times larger.

In the past, you could be sure that all (01234) 77nnnn numbers were using the same provider and were located within the same small geographical area. Now that range will be further split into ten smaller blocks, each potentially a different provider and location.

This has already happened with 08xx and 09xx numbers. With those it can be especially confusing as each small block of numbers might have a different charging structure. Dialling a number that is just one digit different might have a completely different price.

There's certainly quite a few who dial 0207 3xxx xxxx when trying to call the newer (020) 3xxx xxxx numbers.

Less than 45% of London to London calls are dialled using only the eight-figure local number.
More than 55% of London to London calls are dialled using an unnecessary 020 area code, from within the same 020 area.

jrawle wrote on Dec 4^th, 2009 at 10:54pm:


One suspects that mobile companies do not keep records of misdialed calls! Even if they do, I doubt if they break them down according to the local geographic code equivalent to the cell from which the call was made. I am probably not alone in sometimes forgetting that one always has to dial the full number when using a mobile. Furthermore, I am probably also not alone in sometimes forgetting to omit the area code when calling local numbers on a landline when away from home.

As observed previously, Ofcom is probably to blame for making the change from 0171 and 0181 to 020 too simple. Those of us with lists of full (un-punctuated) telephone numbers were able to substitute 0207 and 0208 for 0171 and 0181, as if the one code had replaced the other. There was no extensive spending on a TV advertising campaign to explain that "inner" and "outer" London had been re-united, so as to undo the effect created when it was necessary to explain that they had been split. If Ofcom had been prepared to endure the criticism it would have undoubtedly suffered had it deliberately made that changeover less straightforward  than was necessary, and for causing the additional costs to be incurred, then the present confusion would have been avoided.