cell phone # porting

I have a good guess now of how cell phone number porting is implemented. Had a number transferred from AT&T to Sprint. The phone actually came with a randomly assigned number and a matching MSID (mobile station id), but Sprint told me to re-program the phone with the desired number and a new non-matching MSID in the area code of the desired number.

The porting process was as follows:

  • Immediately, random number stops working, new Sprint-assigned MSID works as phone number!
  • Within minutes, AT&T cuts off connection and accounts access to old number, which ceases to work.
  • Hours later, MSID stops working as phone number, old number now rings new phone.

The fact that the MSID works as a phone number during porting and remains in the phone’s settings, must mean that it is in fact the true “phone number” identifier for the phone. The phone just gives out its stored “phone number” for the purpose of outgoing calls. I’m guessing every carrier has a pool of phone numbers in each area code to give out, and there is a static allocation database somewhere. During porting, Sprint assigns a new number from its own pool, which becomes the MSID. Then AT&T (who owns the old number) changes its databse to forward calls to the old number on to Sprint, instead of processing them internally. Finally, Sprint changes its database to take those incoming calls and forwards them to the assigned MSID.

When you get a new line, a number from the carrier’s pool is assigned so no forwarding is needed, and that must be why the MSID matches the phone number in that case.

Now, if I were to port again to a third carrier, what would they do? Maybe they’ll look up the number and discover they should talk to AT&T?

Here’s some real information which I haven’t read but maybe corroborates or discounts what I wrote. http://www.syniverse.com/pdfs/GuidetoWNP6thedition.pdf


  1. News flash: Bling Bling is played out
    October 7th, 2007 | 16:59
  2. hot thang
    October 24th, 2007 | 14:44

    theory-there is a smis number in settings-however
    I decided to call this phone number it belongs to a person
    has voicemail the whole nine

    Is it possible that this person has access to my phone
    ie, conspiracy theory she is a third number on a phone plan
    i believe only belongs to me and my significant other? if
    so how would I know if this third party is listening to my calls?

    meaning-she knows about me and i dont know about her?
    if this is too far out-or even believable how would i know if
    someone is listening in on my calls

  3. jobsamarin
    November 19th, 2008 | 22:49

    I hope the answer’s will be understandable and that I can beneft from this.


  4. becky
    December 8th, 2008 | 15:52

    i have the same problem. Did u get any info? Please forward to me thanx, becky

  5. November 27th, 2009 | 7:15

    It is always refreshing to read your posts
    check out this video on youtube about cellphone spy: http://www.youtube.com/watch?v=pa8xW-AQGHA
    thanks again and best regards

  6. May 28th, 2010 | 10:27

    It’s usually free. You also control your number after a new bill was passed back in 2004 by President Bush. As long as you pay your bill you are good to port to a new carrier. This website give a timeline for number ports with all the major carriers and prepaids


  7. June 17th, 2010 | 2:26

    i am sorry , i have no idea about this, who can tell me something more?oh…

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