IPhones support both GSM and CDMA. I always by my iPhone at the Apple store so the unlocked phone supports all networks. If an iPhone is bought at AT&T or T-Mobile, the phones only work on GSM networks. I was on the T-Mobile networks for years and now use Verizon. T-Mobile is GSM and Verizon is CDMA.
Kelly On 1/30/18, M. Taylor <[email protected]> wrote: > CDMA vs. GSM: What's the difference between these cellular standards? > By Brendan Hesse - Posted on January 30, 2018 9:04 am > > If you're in the market for a new smartphone or carrier - or you're simply > interested in cell phone networks - you've likely encountered the acronyms > CDMA and GSM before. But what are they, and how do they affect your phone? > > The two cellular standards function in different regions and allow for > global communication between individuals, and each converts incoming and > outgoing data into radio waves differently. Neither should be a huge factor > when buying a cell phone (unlike 4G and LTE), but it's definitely worth > knowing your stuff, since not all cell phones are guaranteed to work on > both > standard. It depends on where you are, what you're looking for, and who > you're with. > > GSM explained > > The iPhone 7 is a smartphone that typically functions on a GSM network. > GSM stands for Global System for Mobile Communication, and unless you live > in the United States or Russia, this is probably the technology your phone > network uses, given it's the standard system for most of the world. GSM > networks use TDMA, which stands for Time Division Multiple Access. TDMA > works by assigning time slots to multiple conversation streams, alternating > them in sequence and switching between each conversation in very short > intervals. During these intervals, phones can transmit their information. > In > order for the network to know which users are connected to the network, > each > phone uses a subscriber identification module card, or SIM card. > SIM cards are one of the key features of GSM networks. They house your > service subscription, network identification, and address book information. > The cards are also used to assign time slots to the phone conversation, and > moreover, they tell the network what services you have access to. They > store > your address book, too, along with relative contact information. They can > even be used to pass information between phones, if a carrier allows it. > > CDMA explained > > The Google Pixel XL is a smartphone that runs on a CDMA network. > CDMA - or Code Division Multiple Access - is often found in the U.S and > Russia, though GSM is also present in those countries. The Allied Forces > developed the technology during World War II, primarily as a method to > prevent Nazi forces from jamming radio signals. Unlike GSM, CDMA grants > users full access to the entire spectrum of bands, thus allowing more users > to connect at any given time. It also encodes each user's individual > conversation via a pseudo-randomized digital sequence, meaning the voice > data remains protected and filtered so that only those participating in the > phone call receive the data. > Phones on CDMA networks do not use SIM cards. Instead, each phone is built > specifically to work on that carrier's network. What does this mean for > consumers? For starters, it means that phones are tied to a carrier and > their bands, so if you decide to change providers, you'll have to buy a new > phone. > > Is one better than the other? > > Huawei's phones very rarely support CDMA > Not necessarily. Both are the global standards for cell communication. The > major factor affecting call quality is the network itself, not the method > it > uses to transmit information. Of course, there are some things to keep in > mind when it comes time to choose between CDMA and GSM phones. For > starters, > CDMA phones without SIM slots are tied to their carriers, and cannot be > transferred to other networks. A Verizon phone could not be transferred to > Sprint's network, for instance, or vice versa. But sometimes it's not as > cut > and dried as all that - although some Verizon devices do use CDMA, they > also > have an unlocked SIM slot, so could be unlocked for use on other networks. > Sprint is less forthcoming with unlocked SIM slots when its devices do > contain one, but you can usually find ways get your carrier to unlock your > phone when you're done with them. > In contrast, GSM phones are fairly easy to unlock and transfer to other > networks. Additionally, third-party manufacturers often sell phones > designed > for GSM networks, since they don't require access to a specific carrier's > bands. GSM phones will even work in countries with compatible GSM networks. > CDMA networks allow for a greater number of users, meaning their capacity > for communication is greater than that of GSM networks. Moreover, CDMA is > the infrastructure on which all 3G networks are based - for both GSM and > CDMA carriers. However, there's now a third type of network that is quickly > becoming the frontrunner in terms of quality, with many major cell phone > companies quickly adopting it. Dubbed LTE for Long-Term Evolution, the > technology represents an evolved form of GSM, and uses a similar technology > as GSM networks. The new standard boasts enhanced voice quality and > functions as the base of high-speed, 4G data networks. In this case, LTE > does have an edge over the competition in terms of overall speed and > quality. > If you're a U.S. customer and wondering what companies use which type of > network, the split is right down the middle: AT&T and T-Mobile are GSM > carriers, while Verizon and Sprint are CDMA. In truth, picking a new phone > or carrier solely based on what standard it adheres to doesn't necessarily > matter because the services, features, phones, and service quality a > network > offers aren't solely dependent on their network infrastructure. So unless > you have a particular need for choosing one over the other, go with the > carrier that best fits your tastes, needs, and budget. > > Original Article at: > https://www.digitaltrends.com/mobile/cdma-vs-gsm-differences-explained/ > > -- > The following information is important for all members of the V iPhone > list. > > If you have any questions or concerns about the running of this list, or if > you feel that a member's post is inappropriate, please contact the owners or > moderators directly rather than posting on the list itself. > > Your V iPhone list moderator is Mark Taylor. Mark can be reached at: > [email protected]. Your list owner is Cara Quinn - you can reach Cara at > [email protected] > > The archives for this list can be searched at: > http://www.mail-archive.com/[email protected]/ > --- > You received this message because you are subscribed to the Google Groups > "VIPhone" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/viphone. > For more options, visit https://groups.google.com/d/optout. > -- The following information is important for all members of the V iPhone list. If you have any questions or concerns about the running of this list, or if you feel that a member's post is inappropriate, please contact the owners or moderators directly rather than posting on the list itself. Your V iPhone list moderator is Mark Taylor. Mark can be reached at: [email protected]. Your list owner is Cara Quinn - you can reach Cara at [email protected] The archives for this list can be searched at: http://www.mail-archive.com/[email protected]/ --- You received this message because you are subscribed to the Google Groups "VIPhone" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/viphone. For more options, visit https://groups.google.com/d/optout.
