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What is an SMS gateway? Explained here.

When you send an SMS message, do you ever wonder what happens after you hit the Send button? The message goes on a crazy trip, extremely fast, to get to the mobile you were trying to reach. The details of that journey vary a little depending on how you sent the message and the recipient, but most of the messages will travel through at least one SMS gateway to get to their destination.

But what exactly is an SMS gateway anyway? In many respects it’s as simple as the name implies: a gateway. Various mobile carriers all have their own computer systems and networks. In order for SMS messages to travel between networks, it has to leave one carrier’s network and enter into another’s gateway where it then is sorted and sent along its way.

When you send messages from your mobile, your network takes care of all that sorting for you. But you can also send SMS messages via an online SMS provider like fastsms. In those cases, the provider is an SMS gateway too. For example, fastsms has connections with 500 mobile networks in over 200 countries. When you send a message through any of our send options (email, NetMessenger or via our API) we take your message and make sure it gets through to the proper network and reaches its destination. Likewise, if you receive SMS messages, they enter our gateway and our system then delivers them to your inbox.

While that may sound quite simple, logistically and technically speaking it can get quite complicated for a number of reasons. First, SMS gateways need to be able to handle bulk SMS messages. And “bulk” here means millions. It takes significant investment in infrastructure to handle that kind of load. Second, in order to have the connections to all those mobile networks we need to have agreements in place with various networks and other SMS gateways. Third, we also need to develop the software to interface to those various gateways. These include our web-based NetMessenger, API and email to SMS service.

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Connecting via our API

When we created our API we wanted it to be simple to use, yet powerful enough to do everything customers would want to do from within an application. We also know that people have preferences when it comes to programming languages and interfaces. So our API supports four different options developers can choose:


Detailed API documentation, SDKs and a sandbox can be found in our Developer Zone, but you can read the highlights here.

PHP Software Developers Kit (SDK)

According to W3techs.com, “PHP is used by 81.6% of all the websites whose server-side programming language we know.” This made it a perfect choice when we were deciding which languages to include because just about anyone with a website is likely to use PHP.

Our PHP SDK is hosted on GitHub. We give you everything you need to get started using PHP to connect your website or application to our systems. You’ll find the source code and examples to send messages, check messages, account balances, create users and lists, reporting, creating users and other functions.


One of the simplest and most popular ways to connect your application to our services is by using our HTTP API. You can connect using HTTP GET or POST. And by passing the relevant parameters, you can access virtually every feature we offer including importing contacts and inbound message forwarding.


Many enterprise applications, such as Oracle, use XML for importing and exporting data. By most reports XML is still heavily used today all across the web too. Our XML API is a perfect fit for integrating into existing applications that already rely on XML. You can download our DTD files from our Developer Zone and even use a live connection to our API to test out the XML interface. You’ll find lots of examples too, and all the information you need to create a robust integration.


For those who choose to develop in .NET, you can get our .NET SDK from github as well. This is a fairly new addition to our API toolset, but one that Windows developers will find useful. In our SDK, you’ll find all you need to get started easily.


We also have a sandbox, accessible from our Developer Zone. Here you can test out the various function calls and see the appropriate API response. In order to use the Sandbox, you’ll need to have your API token. This allows you to have a secure connection with the API which is required even for running tests in the Sandbox.

In fact, whichever way you access our API you’ll need an API token that you can generate from within your account under the Preferences API section. You only have to do this once and it helps keep your account secure. Instead of entering usernames and passwords, your encrypted API token authorises your application to perform the actions requested.

If you’re still deciding on which SMS gateway you want to use, our Developer Zone is available to everyone, not just account holders. So feel free to check it out by clicking on the link and contact us with any questions or requests. We develop all our own software, so when you talk to us, you’re talking to the people who created the system and understand developer’s needs.

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