SMS, Texting, and Messaging in Softphone.Pro: SIP MESSAGE and HTTP API

Recently we proudly announced Softphone.Pro 5.3 and its new features. Inter alia, there is SMS support that expands the possibilities of voice communication by texting and messaging. This article is about protocols, methods, and interfaces by which it's made possible. 


Old but good 

One can hardly call SMS a novelty: the technology appeared in the early 1980s. Nevertheless, it is still commonly used albeit there were several waves of predictions of its imminent demise. There were talks like — communications 2.0, messengers to displace SMS, no one needs it anymore. Anyway, any smartphone in the world fits for SMS by default, though Facebook Messenger to drop SMS support in September. Facebook drops, we find, pal. And what we've found is made via SIP MESSAGE and HTTP API.



There are different ways to send messages from PBX. 

The first one (SIP MESSAGE) is standard and supported by any SIP PBX including Asterisk and FreePBX. In this case you already have everything needed for texting and SMS sending.  

The second way, namely HTTP API, requires an external server and possibly developer involvement; but then it allows not only SMS but as well Whatsapp, Telegram, Viber — whatever.


⚠ NB: as of the date of this article publication Softphone.Pro 5.3 supports SMS sending only. 


To make the picture complete, we shall point SIP SIMPLE also known as RFC6914; SIP MESSAGE is its special case. Both were produced by the IETF and related to Presence and Instant Messaging with the Session Initiation Protocol (SIP). Collectively, these specifications are known as SIP for Instant Messaging and Presence Leveraging Extensions.


Is SIP MESSAGE better than HTTP API?

As noted above, each has advantages. SIP MESSAGE is standard and runs out-of-the-box if a PBX supports such a method. HTTP API capabilities are much broader, there you can implement any idea though it requires some time and resources in terms of development. Should you've got it, you can send messages via any channel — SMS, messengers, you name it. Frankly speaking, as for messengers, we are working on it (oops, announce?).

Replying to the headline — Softphone.Pro 5.3 supports both ways. The only thing required is to choose the most appropriate. Whatever you use, we've prepared the manual for you — here you are.


Not by texting alone 

SMS functionality is the new stage of Softphone.Pro history. Remember, not so long ago it acquired multiple lines and up to 32 SIP accounts support; then appeared nice 50-200% interface scaling, AOD, and transfer features; we also added integration with Jabra and Poly professional headsets as well as a Personal Performance window, that's our concern for agent's work and a contribution to your workflow.

It goes without saying, Softphone.Pro integrates with key CRM software products like Freshdesk and Zendesk, SalesForce and Hubspot, Pipedrive, Zoho CRM, MS Dynamics, Clio — please see the full list in the Settings or on the download page.

By the way, all this splendor might run under your brand: we do White Label for PBX providers and business customers and create individual builds with your logo and corporate colors. 

And that means what? It's time to update and take the best!

To get the latest release, click here.

To know more about White Label, please email us at

Yours truly, softly and phonely, Softphone.Pro 💙

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