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UK phone numbers recognition

Discussion in 'Internet Control Panel (ICP)' started by HAL9000, Jun 11, 2013.

  1. HAL9000

    HAL9000 Member

    trueCall Model:
    trueCall Call Blocker + Recorder
    Continental Europe
    The trueCall Blocker distinguishes phone numbers.
    Because I don't live in the UK, I would like to know how some numbers are composed.
    For example, I've noticed that numbers beginning with 07 are categorized as Radiopaging.

    Could someone explain to me the recognition criteria for the following categories:
    - Special service
    - Mobile Phone
    - Business caller
    - Payphone

    And what is exactly the difference between a "Number unavailable" and a "Withheld number caller"?
    I understand that a "Withheld" is a call with suppressed caller ID and I suppose that an unavailable number was incorrectly transmitted. Is this accurate?
    If so, how does trueCall distinguish this difference? Are withheld numbers transmitted, but tagged to not be displayed?
  2. Top Cat

    Top Cat Administrator Forum Volunteer

    trueCall Model:
    trueCall Classic + Extra + Recorder
    Englishman in Wales!
    07 are typically mobile phones, pagers are rare beasts in these days of mobile SMS. I don't know that a pay phone can be distinguished from any other phone in that STD area. Business callers are either using their standard STD code, or have "non-geographic" 0845 (etc) numbers, 08xx and 03xx are further subdivided into a confusing array of free, low rate, national rate, and premium rate services. This should at least give you some pointers, I'm sure it can be pinned down with a web search.

    A typical racket perpetrated on unsuspecting users is to call a line from a premium rate number (the call costs are shared between the phone company and the line holder), but only ring the line briefly. The naive user thinks they just missed a call and might use their phone ring-back or 1471 to call back. The call connects, but the scammer has a computer which plays the ringing tone down the line, so the caller doesn't realise he has connected, and is clocking up a premium-rate bill listening to a ringing tone.

    Number unavailable comes from PABX systems that do not support CLI, and may possibly also come from ex-directory lines (not sure). There are special codes sent to trigger these displays.
    db1 likes this.
  3. db1

    db1 Member

    trueCall Model:
    trueCall Classic + Extra + Recorder
    BT line - in God's own county
    • 01... and 02... can be interpreted into geographic area codes e.g. 0113... is Leeds, 01274... is Bradford, Bingley, Shipley or Cleckheaton. (all above local to me, basically a greater contiguous area than Bradford alone) 020... are London with only 0203.. 0207.. 0208.. in use, 0238.. is Southampton, 0239.. is Portsmouth, 024.. is Coventry, 028.. is Northern Ireland, 029.. is Cardiff. There can be more granularity in the data, such that you can tell which company is the service provider, except that number porting makes some number information incorrect.
    • 03.. are non geographic
    • 04 is reserved for future use
    • 05.. are corporate, with some legacy special services
    • 06 is reserved
    • 07.. are mobiles with 070.. and 076.. being personal numbering services and radiopaging at higher or fixed per call costs.
    • 08.. are "Special services" usually costly and a complex structure, but some are freephone nos.
    • 09.. are "Premium rate services" i.e. mega-costly e.g. adult services, unlikely to be calling you. Anyone presenting an 09... caller_iD is almost certainly a scammer or confidence trickster.
    • 01 02 03 are now charged at the same rate, but geographic number call costs in the past were based on distance in 4 bands. Payphones are embedded in the 01.. and 02.. space but signally differentiates them and are charged at different rates (and many cannot receive calls back)
    • 01534.. Jersey, 01481.. Guernsey, Alderney, 01624.. Isle of Man. The Channel Islands and Isle of Man are charged as different rates to geographic calls.
    • 0300... 0500... 0800... 0808... are free to the caller.
    • 0845.. was charged as a "local rate call" anywhere in the country, as was 0345.. . 0870.. was a "National rate call", but real geographic call costs came down leaving them at a higher rate but less than special service rates. These are often including in "inclusive calling packages" (weekends, evenings and weekends or anytime). The definition of evening varies with service provider. Often the called company took a cut of the costs split with the provider. 0345 has been cleared of the profiteering and all existing 0345 numbers are either in use or unallocated, any with a corresponding 0845 number are reserved for that corresponding number to be switched.
    • For landlines the 0845.. 0870.. calls can often be included in a call package.
    • For mobiles they are not in inclusive packages, meaning that many calls from mobiles to 0500.., 0800.., 0808.. that would be free from a landline are chargeable calls. those that are free depend on the mobile service provider
    See the ofcom website http://ofcom.org.uk, more specifically http://stakeholders.ofcom.org.uk/telecoms/numbering/
    or http://www.ofcom.org.uk/static/numbering/ (quite technical with regularly updated, sometimes weekly, downloadable files .xls comma delimited text and .pdfs)
    or even The National Telephone Numbering Plan (PDF quite technical)
    Top Cat likes this.
  4. db1

    db1 Member

    trueCall Model:
    trueCall Classic + Extra + Recorder
    BT line - in God's own county
    Number unavailable usually comes from PABX systems, in particular those with ISDN data lines into the switch. But can result from the connections between some service providers and the predominate provider BT (once upon a time part of the GPO and in those days the only government owned POTS provider). BT still control far too many landlines IMHO. But no mobiles.

    Ex directory numbers were often set such that by default they withhold caller_ID. This is an option, but is not the default for new ex-directory numbers. Number unavailable from these only occurs with extremely old rural switches/exchanges which are becoming rare, often coinciding with broadband not spots.

    When analog mobiles first appeared they were only in the 0860.. and 0836.. number spaces. These were eventually migrated by inserting a 7, but the analog system was switched off a while ago. Some people may still have 07860.. or 07836.. numbers which they have retained, admittedly with newer handsets so that they have numbers allocated to them from the time that Cellnet and Vodafone were the only mobile providers.

    There is a set of data extremely similar to caller_ID of which the calling number should match the caller_ID. This is used for billing purposes and is retained within the network(s) BUT is released to the emergency services so that a true caller number is presented on calls to 111, 112, 999 etc.

    Good PABX switches, often with a significant amount of direct dial to extension traffic should present correct caller_ID, but can be set legitimately to display, a reception, switchboard operator or a call hunt group number.
  5. Top Cat

    Top Cat Administrator Forum Volunteer

    trueCall Model:
    trueCall Classic + Extra + Recorder
    Englishman in Wales!
    It is worth mentioning that the definition of "evening" (for inclusive call plans) was shifted from 6pm to 7pm, the cynical view being that people wouldn't notice and continue to make calls from 6pm!

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