GSM vs CDMA

[TubsAlwaysWins]

Anyone know how to tell if a phone is GSM or CDMA? I have a verizon HTC One M9 I am trying to sell and I need to know. I know I need a SIM card and based on what i saw that makes it GSM but im not sure

[it_dont_work]

gsm uses sim as far as I know.

 

People still use cdma? I haven;t owned a cdma phone since the god dam 90's

[it_dont_work]

1 minute ago, wrathoftheturkey said:

Sprint? Verizon? Worst and best, both do.

As an aussie, I've only heard of these names and have noi idea what they are. but on a serious note, the only thing cdma is used for here is older emergency service paging systems. All mobiles use either gsm or utms

[it_dont_work]

1 minute ago, wrathoftheturkey said:

dafuq is utms?

3g/nextg/HSDPA

[Drak3]

35 minutes ago, it_dont_work said:

gsm uses sim as far as I know.

 

People still use cdma? I haven;t owned a cdma phone since the god dam 90's

Both CDMA and GSM are compatible with SIM. In terms of quality and reliability, it comes down the implementation by the carrier, and in majority of scenarios, are about equal. CDMA carriers are still CDMA carriers because of how much they invested early on to achieve their network reliability and quality, and how much it would cost to convert to GSM in a short span of time, especially if they want to make the transition smooth.

[Omon_Ra]

28 minutes ago, it_dont_work said:

As an aussie, I've only heard of these names and have noi idea what they are. but on a serious note, the only thing cdma is used for here is older emergency service paging systems. All mobiles use either gsm or utms

That's understandable; Verizon and Sprint in the USA are really the only CDMA carriers in the world. I think there are a couple other small countries that still are dominantly CDMA, but GSM is pretty much the global standard now. Verizon has used SIM cards for certain devices for a while now, my Blackberry 8830 World Edition (~2007) had a SIM card, but that was because it had CDMA and GSM capabilities. 

 

5 minutes ago, Drak3 said:

 CDMA carriers are still CDMA carriers because of how much they invested early on to achieve their network reliability and quality, and how much it would cost to convert to GSM in a short span of time, especially if they want to make the transition smooth.

Nailed it. But I think in Verizon's case, it's also so they could have more control over what devices are on their network (no unlocked devices).

[Drak3]

6 minutes ago, Omon_Ra said:

Nailed it. But I think in Verizon's case, it's also so they could have more control over what devices are on their network (no unlocked devices).

Verizon using CDMA and their carrier locking practices don't have much, if anything to do with each other. They require carriers to have locked bootloaders and firmware designed to exclude non-Verizon carriers to the phones, in order to sell phones that are "supported" by Verizon officially. Both are 100% possible to do with GSM.

[Omon_Ra]

1 minute ago, Drak3 said:

They require carriers to have locked bootloaders and firmware designed to exclude non-Verizon carriers to the phones, in order to sell phones that are "supported" by Verizon officially.

This is exactly what I meant by:

16 minutes ago, Omon_Ra said:

so they could have more control over what devices are on their network (no unlocked devices).

 

[Drak3]

5 hours ago, Omon_Ra said:

This is exactly what I meant by:

 

You forgot this part of your statement:

5 hours ago, Omon_Ra said:

But I think in Verizon's case, it's also so they could have more control

 

[Omon_Ra]

5 hours ago, Drak3 said:

You forgot this part of your statement:

 

I think we're having a misunderstanding, because it seems we're both arguing the same point: Verizon, whether it was intentional or not, by going with CDMA rather than GSM, has enabled them to 'lock down' what phones they can have on their network. Meaning they have more control over the devices on their network; as an example, they do not support 'unlocked' devices.

[Drak3]

6 hours ago, Omon_Ra said:

I think we're having a misunderstanding, because it seems we're both arguing the same point: Verizon, whether it was intentional or not, by going with CDMA rather than GSM, has enabled them to 'lock down' what phones they can have on their network. Meaning they have more control over the devices on their network; as an example, they do not support 'unlocked' devices.

No, we aren't. Use of CDMA doesn't enable carriers to lock down most phones, as they have the physical hardware to run on multiple CDMA and GSM bands, with the only requirement on locked phones being a ROM swap.

 

Verizon completely supports unlocked devices that are compatible with CDMA, and Verizon devices can be unlocked and brought over to other carriers.

[ItsTurbo]

On 12/29/2016 at 11:47 PM, it_dont_work said:

gsm uses sim as far as I know.

 

People still use cdma? I haven;t owned a cdma phone since the god dam 90's

 

Both use a sim card. Verizon and Sprint use CDMA and my friends all have sim cards in their phones. 

[ItsTurbo]

On 12/29/2016 at 11:42 PM, TubsAlwaysWins said:

Anyone know how to tell if a phone is GSM or CDMA? I have a verizon HTC One M9 I am trying to sell and I need to know. I know I need a SIM card and based on what i saw that makes it GSM but im not sure

 

Sprint and Verizon are CDMA, everyone else I know of uses GSM. T-Mobile, AT&T, Cricket, etc.