GSM vs CDMA

GSM is the way 'tte go

I remember Japan is CDMA as well. Last time I went there, my 3GS couldn't connect to any of the telcos. And since the 3GS is GSM-only, I assumed their telcos are CDMA.

moonman239 said:

GSM:
1) You can transfer your number to any cellphone by simply popping in a SIM card, assuming the card fits.
2) You can do voice and data at the same time.
3) It's the most widely used technology among all the carriers in the world.
CDMA:
1) You have to get your carrier to add some ID belonging to your cellphone to their database before you can use the phone on their network, unless the phone's already configured to run on that network.
2) You CAN'T do voice and data at the same time without two radios or whatever the iPhone 5 has.
3) Unless your phone can be used over a GSM network, the only other country I can think of that uses CDMA is China.

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So basically, you prefer GSM.

At least here in the US, it can be more a matter of choosing a carrier, not just a protocol. I prefer GSM for mostly those same reasons, but after lots of debate, I left AT&T and got on Verizon -- the US's largest CDMA carrier. In the end, I'd rather have the network that has much wider LTE availability and frequently finishes higher in overall testing performed by Root Metrics, AND is usually listed as the preferred network on opensignal.com in many places throughout the country.

Add to this the fact that the Verizon iPhone 5 is unlocked and capable of operating on GSM networks in a pinch, and it's a convincing argument for me.

Just gotta go with what works best for what you want.

Beeplance said:

I remember Japan is CDMA as well. Last time I went there, my 3GS couldn't connect to any of the telcos. And since the 3GS is GSM-only, I assumed their telcos are CDMA.

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Pretty sure you could get GSM service from NTT Docomo

GSM is the most convenient of all

Why is this even an issue, both Verizon and AT&T iPhones are gsm, it's not like there are any drawbacks to owning a Verizon iPhone like on the old CDMA only iP4.

moonman239 said:

GSM:
1) You can transfer your number to any cellphone by simply popping in a SIM card, assuming the card fits.
2) You can do voice and data at the same time.
3) It's the most widely used technology among all the carriers in the world.
CDMA:
1) You have to get your carrier to add some ID belonging to your cellphone to their database before you can use the phone on their network, unless the phone's already configured to run on that network.
2) You CAN'T do voice and data at the same time without two radios or whatever the iPhone 5 has.
3) Unless your phone can be used over a GSM network, the only other country I can think of that uses CDMA is China.

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Definitely convenient.

However a few things.

With CDMA voice + data is a limit of only the CDMA radio. If you are in a 4g coverage zone (WiMax or LTE) you can do data plus voice.

In general with CDMA you will have less dropped calls, especially when traveling between cellular cells.

CDMA voice quality is superior.

CDMA is more secure.

Hopefully these comparisons become less Relevant in the future and cellular providers move to some sort of a VoIP solution over 4g.

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haddman said:

Why is this even an issue, both Verizon and AT&T iPhones are gsm, it's not like there are any drawbacks to owning a Verizon iPhone like on the old CDMA only iP4.

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Umm you are mistaken. While the vzw ip5 is a world phone with a gsm slot, the vzw is a CDMA network, and they also have a LTE network.

http://en.wikipedia.org/wiki/Verizon_Wireless

SporkLover said:

Definitely convenient.

However a few things.

With CDMA voice + data is a limit of only the CDMA radio. If you are in a 4g coverage zone (WiMax or LTE) you can do data plus voice.

In general with CDMA you will have less dropped calls, especially when traveling between cellular cells.

CDMA voice quality is superior.

CDMA is more secure.

Hopefully these comparisons become less Relevant in the future and cellular providers move to some sort of a VoIP solution over 4g.

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Umm you are mistaken. While the vzw ip5 is a world phone with a gsm slot, the vzw is a CDMA network, and they also have a LTE network.

http://en.wikipedia.org/wiki/Verizon_Wireless

Click to expand...

You're not talking about the iPhone when you say data plus voice in lte zone right? Because when I'm on LTE I still lose a data connection.

SporkLover said:

Definitely convenient.

However a few things.

With CDMA voice + data is a limit of only the CDMA radio. If you are in a 4g coverage zone (WiMax or LTE) you can do data plus voice.

In general with CDMA you will have less dropped calls, especially when traveling between cellular cells.

CDMA voice quality is superior.

CDMA is more secure.

Hopefully these comparisons become less Relevant in the future and cellular providers move to some sort of a VoIP solution over 4g.

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Umm you are mistaken. While the vzw ip5 is a world phone with a gsm slot, the vzw is a CDMA network, and they also have a LTE network.

http://en.wikipedia.org/wiki/Verizon_Wireless

Click to expand...

You can only do LTE + voice if the phone uses separate antennas for it. The Verizon iPhone 5 cannot do this even when connected to LTE unfortunately.

Another thing to add on your list is that GSM is way faster on its 3G than is CDMA on their 3G.

It also doesn't split text messages over 160 letters into 2 or more messages, which sometimes get scrambled in the wrong order.

wordoflife said:

Another thing to add on your list is that GSM is way faster on its 3G than is CDMA on their 3G.

It also doesn't split text messages over 160 letters into 2 or more messages, which sometimes get scrambled in the wrong order.

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mmy iPhone 4 and 3G did the 160 letter things, it's a limit of text messaging.

Ahh yes. I was a bit too open. The iPhone 5 is the exception to simulteonous data and voice because of the lack of an extra antenna. As far as I know, every other CDMA 4g phone has that capability.

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tymaster50 said:

mmy iPhone 4 and 3G did the 160 letter things, it's a limit of text messaging.

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X2. That's a software limitation not a technology limitation. I had dumb phones on sprint that split messages.

I thought that with verizon, the iphone 5 you can just swap sim cards to another iphone5 just as easily, well at least i think its the case for off contract iphones.?????

jmflo571 said:

I thought that with verizon, the iphone 5 you can just swap sim cards to another iphone5 just as easily, well at least i think its the case for off contract iphones.?????

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Changing between Verizon 4g phone is as easy as just switching the sim card, not limited to the iPhone.