SureM Voice services

SureM provides automated calling service which sends messages in voice to subscribers.

There are two types of voice services; TTS (Text to Speech) and ACS (Automated-calling service).

1. TTS(Text to Speech)

Text-to-speech reads out the content of the message into machine-synthesized audible speech.

Service Flow


How to Use:
  • Pricing:Different for each countries and is charged per second.
  • Options:Different languages and voices to choose from.

※ Please contact us for consultation.

2. ACS(Automated-Calling Service)

Automated-calling service plays recorded speech in any languages to the recipients.

Service Flow

serviceflowIn a case of delivering verification code: Fail to delivery verification code through SMS

Benefits of ACS
  • A subscriber can still receive the verification code when a text message cannot be delivered.
  • A subscriber is given a choice to make to receive a voice call instead of a text message.
  • Speech can be recorded in different languages to suit the recipients that makes it much easier and more convenient for the recipients.
How to Use
  • Pricing:Different for each countries and is charged per second.
  • Options: Choose the language of speech for different countries.

※ Please contact us for consultation at


What is two-factor authentication (2fa) ?

What is two-factor authentication?

Two-factor authentication (2FA) is a second level verification process when accessing your account. The first level commonly is a simple combination of login+password and for the longest time, that was the only method used by various websites and applications.

Over the past few years, people have become more and more aware of cybersecurity and various websites and services are now introducing multiple levels of identification to protect their customers.

The general idea is that the 1st level of verification is to simply confirm that the entered username exists by providing the password matching it. The 2nd level serves as identity verification – the person who entered the username and password IS indeed the owner of the device/account and has the right to take any actions with it.

What types of 2fa exist?

The most commonly known and used methods are :

  • SMS codes (receiving on your mobile phone)
  • Applications auto-generating the codes (e.g. Google OTP)
  • Passcode cards or other similar forms of pre-approved code lists (used by the banks, for example)


How does 2fa work?

Every time you log in to the account you receive a new code, which is where the name came from – OTP (one-time passwords). Usually, most websites offer an option between the two – either using SMS authentication or an app.

With SMS you must follow the instructions given and enter your existing phone number to receive SMS on it (often the same mobile number that was used upon registration is required). NOTE: some people try to use virtual numbers for registration and following 2fa but it is never a good idea (and we will explain in the next blog post why).

If you prefer using an app, something like Google OTP, the procedure is even easier – the first time you register and use the app follow the instructions to connect it with your account on the website. Once connected, every time you log in, the app will generate a random code that has to be entered.

If you have any questions on 2fa via SMS, feel free to contact SureM managers at

Complete Guide to Korean promo / advertisement SMS

In this digital age, more and more people are concerned with the issues of cyber-security and protection of personal information. For companies in the IT-business, as well as any other enterprise, communicating with their customers using the modern technological tools and applications, this subject is extremely hot.

All the countries are introducing strict policies in terms of SPAM prevention to protect their citizens from constant disturbance by the unwanted flood of advertisement messages, and the corporations from highly expensive lawsuits.

South Korean laws (namely, Korean Telecommunications Policy on Spam Prevention, 2014) contain some general guidelines on sending promotional traffic to Korean mobile phone users. The main points to consider are (ref. to picture below) :

  1. Header (광고) – in Korean it means “ad, advertisement” and serves the purpose of notifying the handset users that the message they received is of promotional nature. Whether or not the message itself is written in English, Chinese or any other language – the Header has to be attached by the Sending company in Korean.
  2. Compulsory opt-out – at the bottom of the message, an opt-out option has to be added, so that any handset user could unsubscribe from getting any more promotional messages in the future.

Promo SMS copy

To ensure high delivery rate, the best option is to consult with the SMS provider before sending the traffic. You may contact our specialists to receive full consultation regarding sending promotional messages to South Korea ( and not only)



2-way SMS

2-way SMS service – a combination of MT and MO services, allowing the CLIENT to transmit messages and receive replies from the End User.

The service is provided through a virtual number, issued by the provider. Depending on the destination country, virtual numbers can be presented by long codes, short codes or standard phone numbers.


  1. Short code : 114, 4565,.. (usually up to 5-6 digits)
  2. Long code : 0133-xxxx-xxx (Korea) (special virtual number, does not look like a real phone number; issued by designated entity in each country)
  3. Standard phone number : 7-914-xxx-xx-xx, 82-10-xxxx-xxxx (in some countries Mobile carriers provide numbers similar to standard mobile numbers)

2-way service is widely used for various purposes:

  • Advertisement opt-out (unsubscribing)
  • Customer care lines (*with TOLL-free numbers)
  • Polls and surveys
  • Marketing campaigns



SureM 2-way SMS service flow

Korea : mobile number verification (본인 인증)

When signing up for almost any mobile app / online store / banking service in South Korea, every user is required to go through mobile phone number verification process.

There are 2 types of verification : general verification and advanced verification.

  1. General Verification (일반 본인인증)

General verification consists of 1 level check – simply confirming that the phone number is used by the person, registering for the service. The information required is only mobile phone number.

By entering the code received via SMS, verification process is completed.


left image : enter phone number / right  image : enter code received by SMS

This type of verification is mostly used by online stores, music libraries etc.

2. Advanced verification (고급 본인인증)

The goal of advanced verification is to confirm that the legal owner of the phone number is indeed in possession of it and can use it for account registration. The information required for advanced verification :

  • Full name (as stated in contract with mobile carrier SKT, KT, LGU+)
  • Date of birth (y or yyyymmdd)
  • Choose Male / Female checkbox
  • Choose Korean / Foreigner checkbox
  • Choose carrier (SKT, KT, LGU+) -> enter mobile phone number
    • Enter code received via SMS


Advanced verification is commonly used by banks, public institutions, hospitals etc – any organizations, where the service involves higher level personal information required for its provision.

To know more about mobile number verification in Korea and get a quote please contact our managers at

Sending SMS to South Korea

  • Guarantee the highest success rate for the traffic sending to Korea
    • (1)We have accumulated full NPDB of three mobile operators for 17 years of experience
      • In Korea, there is Number Portability service provided by main three operators
      • E.g. 010-1234-5678 number, originally belonging to KT can switch to another operator (SKT or LGU+)
      • Fast transmission to the connected operator based on all NPDB information
        (NPDB : Number Portability data base)
    • (2)Supporting messages receipt without blocking from the SPAM policy
      • On 2014, Offered Guideline about transmission of advertising message
      • On 2015, the policy has been revised for filtering SPAM (Enforced on October 2015)
        • ·Policy enforcement to prohibit changing sender ID randomly
        • ·Service implementation to block sending message with stolen number
      • =>We provide a guideline to the customer to send a message which is fitted in the government policy
      • <In case of sending SMS with unavailable sender id or
        sender id which is not match to the numbering plan in Korea >[Failure of Detailed rules] [Proper examples]
    • (3)Possible to send to the minor operators
      • Transmission to the phones connected with KT Powertel , Ann Phone and Internet Phone
      • Numbering system according to the kind of service
        • ·SKT, KT, LGU+ : +82 – 10 – XXXX – YYYY
        • ·Internet phone : +82 – 70 – XXXX – YYYY
        • ·Seoul Landline/ Internet phone : +82 – 2 – XXXX – YYYY
        • ·Other destinations Landline / Internet phones : +82 – 31 – XXX – YYYY
          • ※Other destinations: Gyeonggi (31), Incheon (32), Gangwon (33) and Chungnam (41), Daejeon (42),
            Chungbuk (43), Sejong (44), Busan (51), Ulsan (52), Daegu (53), Gyeongbuk (54), Gyeongnam (55),
            Jeonnam (61), Gwangju (62), Jeonbuk (63) and Jeju (64)
        • ·KT Powertel : +82 – 13 – XXXX
    • (4)Tracing the reason of failed message and issuing weekly report for increasing success rate
      • Delivery rate improvement 70% -> 96%
        • ·The actual successful delivery rate is considered as 100%
          because the failed message of 4% is caused by the reasons below.
        • ·The reason of Failure : Invalid phone numbers or handset power off
      • Delivery rate improvement grounds (failure cause analysis and response)
        • ·Sender ID regulations compliance guide
        • ·Solution for Number Theft Protection Service
        • ·Error code status for non-existent numbers
        • ·Special solution for multilingual messages that are delivered incorrectly
  • Supporting to send messages in multi-language and higher quality service only in Korea
    • (1)All languages supported
      • You may send messages in English, Japanese, Chinese etc.
      • Full multilingual coverage (send messages in any language to any country of the world).
      • [Other company] [SureM]
      • [Other company] [SureM]
      • [Other company] [SureM]
    • (2)Unlike any other A2P providers, we can deliver 140 byte SMS to Korean handsets!
    • (3)Individual 1:1 Customer Management service (with designated Account Manager)
      • Your personal Account Manager is always ready to assist on any possible enquiries and provide the information on successfully transmitted, non-transmitted messages, delivery rate and total indicators in a report, based real-time monitoring system and provide consultations based on the data.
    • (4)Weekly reports
      • Transmission details, delivery rate information provided