Hacker News Reader

Comment by rmc | Hacker News Reader

No I don't think so. Everwhere else on the world is GSM. That confused me when I first read about USA mobile phones, I wondered what this CDMA thing was.

View on HN

No. CDMA is used also outside the US.

* KDDI, Japan's #2 carrier: http://en.wikipedia.org/wiki/KDDI (20-21M users)

* China Telecom http://en.wikipedia.org/wiki/China_Telecom (216M users)

Also others in India too. For instance.

Also, Iraq. Thanks, Darrell Issa!

There are GSM networks in the rest of the world yes, but that is not the only technology outside the US. There are CDMA networks in other countries as well. See: http://en.wikipedia.org/wiki/Cellular_frequencies#Other_Regi...

It's on a different frequency and uses a different communication protocol.

There are a few Verizon phones that are "world phones" meaning they can operate on CDMA and GSM, so you can take them out of the country with you.

I've brought my CDMA phone with me a few times and more or less got by on wifi for data needs (I wasn't going to pay the ridiculous international call fees anyway, last time I did that with my iPhone a 20 minutes of calltime and a few emails cost me over $150!)

While it seems not technically right, e.g. CDMA seems to be used here and there around the world, I am reassured in my opinion that if you intend to use your cell phone/modem not exclusively on your home operator's network, you'd better stick to GSM.

Thanks for your links, retroafroman and dboyd! That's exactly what I needed.

Worldwide CDMA coverage: http://www.cdg.org/worldwide/

Looking at their map, it's highly misleading, implying there's CDMA 3G coverage in a bunch of places where there is no, or minimal coverage. (They're a trade body promoting CDMA -- what would you do in their shoes?)

CDMA2000 aka EV-DO isn't compatible with W-CDMA, aka UMTS -- the 3G standard used just about everywhere -- and has about 10% of the market worldwide:

https://secure.wikimedia.org/wikipedia/en/wiki/Comparison_of...

Here's a list of CDMA2000 operators. You'll notice a lot in the Americas, especially the USA, plus others scattered elsewhere:

https://secure.wikimedia.org/wikipedia/en/wiki/List_of_CDMA2...

And here's the giant table of UMTS (aka W-CDMA) operators worldwide:

https://secure.wikimedia.org/wikipedia/en/wiki/List_of_UMTS_...

If you're American and don't have a passport, then by all means get a Verizon iPhone 4. But if you expect to travel widely it'd be much more sensible to get a GSM/UMTS iPhone 4, even if it means putting up with AT&T at home. (More sensibly, buy an unlocked one from Apple on a trip to, say, the UK or Ireland: claim back the VAT and buy a micro-SIM on the network of your choice and you're golden.)

> They're a trade body promoting CDMA -- what would you do in their shoes?

I would either tell the truth or quit the job. I take my professional code very seriously.

Very misleading. It highlights Ireland as a CDMA country (there's a trial apparently) However if you had a CDMA mobile phone, it won't work in Ireland.

Reply on news.ycombinator.com