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Comprehensive testing of SMSCs is essential for ensuring successful delivery of SMS services

Comprehensive testing of SMSCs is essential for ensuring successful delivery of SMS services


Comprehensive testing of SMSCs is essential for ensuring successful delivery of SMS services

SMS remains a key capability, so simulating realistic end-device traffic over SMSCs and SMS gateways is essential to ensure that service delivery is maintained to the highest standards.

Even with the rise of OTT messaging apps such as WhatsApp, Twitter, and Facebook, SMS texting is here to stay. Statistics show that 98 per cent of all text messages get opened, compared to only 20 per cent of emails that get opened[1]

In fact, up to 63 per cent of users worldwide use the default texting app on their mobile phones over OTT messaging apps1. It’s not just consumers that prefer to use SMS, businesses sent 2.7 trillion text messages in 2020, with 48 per cent of customers preferring direct communication from businesses through text messages, compared to other mobile marketing channels1.

It means that SMS is not a channel that MNOs and other service providers can afford to ignore. Despite the current focus on advanced 5G networks and use cases, simple SMS texting will remain the channel of choice for the majority of consumers and businesses alike.

The portion of the network that handles text message operations is known as the short message service centre (SMSC). It’s responsible for receiving, storing, routing, and forwarding SMS messages to and from mobile devices.

When a user sends an SMS message from a mobile phone it is sent directly to the SMSC, which then sends a message back to the device saying it has received the message, and then sends the original message on to its destination. If the recipient is on the same network, the message travels directly to their mobile device – if the device is off or out of coverage, the message is stored by the SMSC until the recipient is back online, then it is sent.

If the recipient is with another network provider, the message must pass through an SMS gateway, which ensures the rapid transit of SMS messages between users on different networks.

Network providers usually manage their own SMSC(s) and locate them inside their wireless network system. However, it is possible for a network operator to use a third-party SMSC that is located outside the wireless network system. Similarly, business customers may also connect to SMSCs, via the Short Message Peer to Peer (SMPP) protocol. SMPP is an open, industry standard used to provide a flexible communications protocol for the transfer of SMS texts between networks under the TCP protocol. Put simply, SMSCs are essential for providing SMS capabilities.

It also means that testing the reliability, scalability and operational functionality of SMSCs and SMS gateways  is a significant task. Ensuring they continue to deliver is an ongoing operational consideration. As a result, MNOs need to be able to simulate realistic traffic loads, and end-user behaviours. How can you do this?

Emblasoft Evolver is a comprehensive set of tools within a single platform that can simulate end-client behaviour at the protocol level using a full-stack implementation. Parameters can be set and manipulated to simulate customer-specific client behaviour. Emblasoft provides soft client agents that receive and interact with simulated SMS traffic. Tests can be customised and automated, making multiple, iterative tests fast and efficient.

Evolver can also be used to test SMS A2P traffic. For enterprise A to send a message to customer (list) B, requires several parties:

  1. An enterprise wanting to send automated bulk SMS.
  2. SMS platform providers.
  3. MNOs who deliver the message, which is likely to require multiple interconnections between potentially several hundred different operators such as BT, O2, Vodafone, and so on (the customers’ providers).
  4. SMS hubs used by operators and carriers to reach further multiple operators that may be too small to deal with directly.

It, therefore, requires comprehensive testing to validate every step of the way to assure service performance. Different interconnections need to be stress-tested, along with sent/received rates, measuring message volumes and applying active monitoring to detect any issues before they impact the customer.

Emblasoft Evolver enables high-performance, scalable SMS A2P messaging by testing and validating services across the entire core infrastructure.

To find out more about how Emblasoft can help you guarantee SMS QoS now and in the future, visit, or download our white paper on testing SMS A2P, RCS and RBM services here.