Starting SMS Business as an addition to VoIP

We discussed basic principles of VoIP operation in the previous post. Now lets discuss logical continuation: SMS.

SMS or Short Message Service is an integral part of the mobile communications and it has been around for almost as long as mobile calling in the shape of GSM. Despite widespread availability of messaging apps like Whatsapp, Telegram and likes, SMS has not lost its importance due to to several reasons:

1. Widespread availability: Short Message service unlike messaging apps does not rely on data newtork. Instead it uses GSM native infrastructure to transmit messages, and therefore is available (almost) always whenever there is a signal coverage. It is possible to send and receive short messages from/to any phone, it does not have to be a smartphone, and not even the feature phone;
2. Early adoption and integration: since it was there since very beginnings of the GSM networks, the users are well accustomed to use it, SMS came as an integral part of the phones so the users usually identify messaging with SMS;
3. Backing from carriers: SMS is quite good revenue source from mobile operators, so they are interested to keep it up and running. Unlike messaging apps which are able to use Wifi networks and avoid charges, in the case of Short Messaging operators are in control of the traffic, and apply per-usage fees which sometimes can be surprisingly high.
4. Security: The often forgotten aspect of the SMS messaging is guaranteed delivery to the intended device. Let's illustrate this by example: if you take the SIM card out of the phone and insert different SIM card, you are no longer the same user, i.e. you cannot receive messages sent to this user anyway, since the identity of the recipient has left the phone along with the SIM card. It is opposite with messaging apps like Whatsapp and Telegram - you usually need to prove your identity (phone number) only once, when registering the app. If you later take the SIM card out of the phone, messages can still be sent/received to the same user as if nothing was changed. This feature of the SMS is ofter used in One Time Password applications, as discussed in this previous post. 

Given the above list, what are the applications of SMS for VoIP operators? Lets see some of the possibilities:

1. Offer VoIP users logical addition- short messaging. Many DID number providers now offer DID numbers which are also SMS enabled. That means that along with voice, VoIP operators now can offer also SMS.
2. Application to Person or A2P: these are automatically generated messages of different types. One example above was mentioned: one time passwords or OTPs. Different service providers use SMS for automatic order confirmations, notifications, etc. All of these usually happen without human intervention, and do not require reply, therefore this case even does not require SMS enabled DID numbers.
3. Marketing: SMS based marketing is very widely used in many countries: sending out bulk SMS campaigns, setting up polling, voting, sending out discount vouchers, etc. SMS marketing is in some aspects very similar to email marketing, but with some notable exceptions: it has higher cost per message, however, it is known that it will be read with much higher probability unlike with email which can easily end up in spam filter or be moved to bin without reading. These cases can make use of two-way messaging by use of SMS enabled DIDs. Toll free SMS DID numbers are popular new addition (e. g. 1-800 numbers in USA) where people can send toll free messages similarly like it was with voice calling. SMS can be great addition to call centers.

These are few areas where VoIP operators can start with SMS utilizing their existing customer base and knowledge of the operations in telecommunication industry.

In one of the next articles we will discuss pieces needed to set up SMS operation: equipment (like ESME) and protocols (like SMPP or HTTP).

UPDATE 2019-03-01: See newest entry about Types of SMS Services Small Operators can offer.