How to use your phone in South Korea

If you are trying to use your phone in South Korea (Korea from now.), you would have found out that it's not as easy as it is in other countries. While all you have to do in other countries is to get a SIM, swipe in, and talk it's not the case in Korea.

Before we get started, there is a requirement for your phone to be used on Korean networks.


Your phone should meet either standard.

CDMA 800Mhz / UMTS (WCDMA,3G,whatever you call it.) 2100Mhz

If you're on Verizon, Sprint PCS (not NEXTEL), Alltel, USCC, etc your phone should not have a problem since they all utilize CDMA 800Mhz along with the 1900Mhz band.


However, if you're on AT&T, T-Mobile, Unicel, and other GSM providers you should check if your phone has 3G capability and right frequency. (Some phones on AT&T and T-Mobile do have 3G capability but only have 850/1700 or 1900Mhz support.)



Congratulations to those of you who own the 'right' phone.

There are two ways to use your phone in Korea.


1.Roam
2.Get the authentication

I'm not going to talk about how to roam in this article since you don't even have to look in to your phone's manual to do that. You phone has the necessary frequency(ies) for Korea roaming? Bring it, it's going to work simultaneously.


Now, the authentication process. You might wonder why this process is needed as you will recall how it works in other countries.

Korean telecommunication system is very closed inside. It did not have any other network than CDMA 800Mhz before it was 2004, when SK Telecom and KT (former KTF) commercially launched UMTS 2100Mhz network.

Although their networks use USIM, their networks run whitelist database. That is, while operators in other countries only blacklist stolen handsets so people can use phones from other providers and countries freely. It's not the case in Korea. Korean providers ONLY allow phones branded and sold by them to be registered on their networks.


If you want to use the phone on Korean networks, you have to get the authentification. Again, Korea is one of the most 'closed' countries.


There are two ways.

1.Radio Research Agency (RRA from now.)
2.Private companies

RRA costs less (KRW 360,190) but takes longer time and energy (five weeks and you have to go visit them yourself. No package, no pick-ups, no door to doors.).

Private companies, on the other hand takes shorter time and energy (one to two weeks and you can send your phone in by postal services) but costs more (KRW 500,000).


If you choose to do it via private companies, you can visit http://kes.co.kr or any company on your preference.


If you want to do it with RRA, you can visit http://rra.go.kr.

I'm not sure if either organisations have English speakers. Hope they do but if they do not, you can always leave a comment or email me for help.

Korean IMEI Issues

If you live in a country with GSM based networks, (which will cover most of you) you should know how easy to get a new phone. Buy one, take the battery cover off, and slip a SIM in then you're good to go.

Well, this doesn't apply to South Korea. There are three kinds of networks here.

CDMA, WCDMA, and iDen.

CDMA and iDen has nothing much to talk about IMEI's. What is wrong with WCDMA IMEI is that all of the providers are whitelisting IMEI's. They only allow phones with IMEI's in their database to be registered on the network.

To make it easier, if you bring a WCDMA (or 3G) phone to South Korea and put a Korean SIM into your phone it would NOT work.

Now, if you roaming then your phone would work but local SIM's do not work with your phone even it has supported frequencies, etc or I can say technologicaly suitable, Korean networks would not welcome any foreign phones.

Quite stupid huh.. But believe me they've been doing this for more than 10 years. (including time when they only had CDMA networks. they whitelisted ESN's.)

Got Samsung Glyde

Here it is. My new toy called Samsung Glyde. It's also called SCH-U940 if you like it this way.

It's now connected on SK Telecom network. Voice call, SMS enabled. All of the other function including MMS, IM, web browser - gone.

I surfed the web a little and I've found out that they've got a new update for this phone, version BI29 which adds widget shortcuts and white color scheme.

Mine still has old BF25 with Croix scheme and shortcuts. I'm considering about getting an update. The thing is... How the hell am I going to get it? I'm in South Korea and as far as I know.. no Verizon store exists here.


I'll figure it out anyway.. (of course... in different way than sending the phone back to the states, paying fifty bucks.)