sim unlock

A SIM lock, simlock, network lock, carrier lock or (master) subsidy lock is a technical restriction built into GSM and CDMA mobile phones by mobile phone manufacturers for use by service providers to restrict the use of these phones to specific countries and/or networks. This is in contrast to a phone (retrospectively called SIM-free or unlocked) that does not impose any SIM restrictions.
Generally phones can be locked to accept only SIM cards with certain International Mobile Subscriber Identities (IMSIs); IMSIs may be restricted by:

Mobile country code (MCC; e.g., will only work with SIM issued in one country)
Mobile network code (MNC; e.g., AT&T Mobility, T-Mobile, Vodafone, Bell Mobility etc.)
Mobile subscriber identification number (MSIN; i.e., only one SIM can be used with the phone)Additionally, some phones, especially Nokia phones, are locked by group IDs (GIDs), restricting them to a single Mobile virtual network operator (MVNO) of a certain operator.
Most mobile phones can be unlocked to work with any GSM network provider, but the phone may still display the original branding and may not support features of the new carrier. Besides the locking, phones may also have firmware installed on them which is specific to the network provider. For example, a Vodafone or Telstra branded phone in Australia will display the relevant logo and may only support features provided by that network (e.g. Vodafone Live!). This firmware is installed by the service provider and is separate from the locking mechanism. Most phones can be unbranded by reflashing a different firmware version, a procedure recommended for advanced users only. The reason many network providers SIM lock their phones is that they offer phones at a discount to customers in exchange for a contract to pay for the use of the network for a specified time period, usually between one and three years. This business model allows the company to recoup the cost of the phone over the life of the contract. Such discounts are worth up to several hundred US dollars. If the phones were not locked, users might sign a contract with one company, get the discounted phone, then stop paying the monthly bill (thus breaking the contract) and start using the phone on another network or even sell the phone for a profit. SIM locking curbs this by prohibiting change of network (using a new SIM).
In some countries, SIM locking is very common if subsidized phones are sold with prepaid contracts. It is important to note, however, that the technology associated with the phone must be compatible with the technology being used by the network carrier. A GSM cell phone will only work with a GSM carrier and will not work on a CDMA network provider. Likewise, a CDMA cell phone will only work with a CDMA carrier and will not work on a GSM network provider. Note that newer (2013+) high end mobile phones are capable of supporting both CDMA and GSM technologies, allowing customers to use their mobile devices on any network. Examples of these mobile devices are the Apple iPhone 5c, 6 and newer, Motorola's G4, G5, X Pure, Samsung's Galaxy S6, S7, S8 smart phones, mostly phones based on a Qualcomm Snapdragon chipset or radio.
In some jurisdictions, such as Canada, Chile, China, Israel, and Singapore, it is îllégâl for providers to sell SIM locked devices. In other countries, carriers may not be required to unlock devices or may require the consumer to pay a fee for unlocking.
Unlocking the phone, however, is almost universally legal. Additionally, it is often legal for carriers to force SIM locks for certain amounts of time, varying by region.

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  1. A

    Help, sony xperia 10 III sim unlock.

    Pa help nmn po pano ma open line ung sony xperia 10 III ng anak ko.
  2. S

    Help SIM UNLOCK CODE sa B312-939 po

    B312-939 BAKA LANG NAMAN POMAY IDEA PO KAYO SALAMAT PO.
  3. Z

    Closed Closed Thread

    Meron bang website na legit/recommendation na naa-unlock via GUI lang?
  4. D

    Help Help Sim unlock Samsung Galaxy Tab A

    Mayroon pa puba way to openline yung tablet? Bought from Smart noon pero natapos na warranty and plan so balak na po iopenline para magamit as hotspot. Mabagal po kasi smart dito sa area namin
  5. C

    Help Sim Unlock

    Mga boss pa help naman paano ko ma unlock ung second sim ng phone ko? need kasi ng unlock code may way ba para ma unlock to? Phone: S10+
  6. D

    Help SIM UNLOCK ANDROID?????

    Patulong po mga master. How to unlock alcatel 1c? Ito po imei: 355399090891406
  7. Z

    Kamusta blocking sa sun niyo

    Himala, almost 29Hours na lumipas bago yung huling unblock ko hanggang ngayon wala pang blocking,kahapon nag unblock ako 8:40 PM something ehh sa inyo rin ba nagkaganito except lang dun sa mga di pa talaga nabablock.
  8. B

    J2 pro sim unlock done

    H2 pro sim unlock done By: samkey
  9. P

    Help Openline sim unlock s7

    Pahelp naman po paopenline s7 from canada IMEI 356252075712593 sana po may makatulong salamat po. Student lang po walang pampaopenline
  10. J

    Help Pa sim unlock po

    Unit : Alcatel A30 tablet IMEI: 014899001876993 Carrier: T Mobile from US Sana may makatulong.
  11. D

    Help Pa openline po sony xperia m4 aqua

    mga ma'3am and sir pa openline po sana ng sony xperia m4 aqua po yung sim unlock para magamit sa globe po. brand: Sony Model: E2353 IMEI: 35910006-109732-0 sana po matulungan nyo po ako :)
  12. K

    Help!. how to openline lg g3 international

    How to openline my LG g3 International
  13. I

    Closed Iphone sim unlock

    Hey guys, I was just wondering sino may alam pano mag unlock ng smart locked na iphone hehehhe thankssss
  14. D

    Help Sun cellular sim blocked data connection

    Hello mga ka PHC ask ko lang kung meron din sa inyo na blocked data din yung simcard ng sun? hindi ko na nagamit yung sim ko last saturday ng hapon hanggang ngayon, at kung meron kayo alam na pang unblocked ng sun sim. Daghang salamat ka PHC.
  15. E

    Closed Sim unlock for globe

    Anyone can help to provide SIM UNLOCK CODE procedure for Globe Android phone? Eugene2017
  16. B

    Closed Help sim unlock code

    Mga ser paturo naman po kung sino marunong mag unlock/openline. T-mobile carrier po Nabili ko htc one m7 lollipop 5.0.2 na ask ko lng po kng sino may alam or yung kyang mag generate ng code gamit imei salamat po.
  17. E

    Closed sim unlock

    pa help nmn alcatel sim lock sun model OT 4030E PA help namn po
  18. P

    Closed (HELP) sim unlocking Samsung Galaxy Grand

    Patulong naman po mag sim unlock ng samsung galaxy grand duos Using android application. TIA
  19. O

    JUNE 11 - HELP PO SA SIMBLOCKED.. MGA KUYA AT ATE :(

    MAY SIM CARD AKO NA MGA NAKABLOCK.. NAGTRY NA AKO SA VIA TEXT NG ROAM OFF AT WBTRICK NI KUYA RICHARDRR.. PERO USELESS PARIN.. DI KO NA ALAM GAGAWIN KO DITO KUNG TATAPON KO NALANG MGA TO PARA ATLEAST TANGGAP KO NA.. HUHU SANA MAY MAKAPAG SUGGEST NG ALTERNATIVE WAY NA EFFECTIVE.. SALAMAT SA...
  20. L

    Closed Samsung Galaxy SIV SIM Card Unlocking

    It is tested only on Samsung Galaxy I9505 Instructions: Step 1 : Dial *#0011# Step 2 : press Menu then tap BACK Step 3: press the Menu again the tap KEY INPUT then enter 1, press OK buttonStep 4: press Menu then tap BACK Your are now in the SERVICE MODE MAIN MENU Tap [1]UMTS...
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