SMS and Data Roaming was build upon the same principles used to enable voice roaming. When you travel abroad and you turn your handset or laptop on, it attempts to communicate with a GSM or 3G network. Your handset maybe re configured to actively choose a preferred network in the visited country, but you can choose your own preferred network via the handset menu. The visited (local) network picks up the signal from your device, notes that you are a visitor and attempts to identify your home network. If there is a data roaming agreement between your home network and the visited network abroad and your network operator allows you to roam, your device will then be able to access data roaming services. In some cases, the visited network may only offer basic data services such as SMS and GPRS – Enabled services, such as e-mail, but not 3G/mobile broadband services (e.g. if the visited operator has not rolled out a 3G network or if the home and visited operators have not yet signed a 3G roaming agreement).
What happens when you send an SMS while abroad?
- When you are abroad and you send an SMS home to a friend, your SMS is managed by the visited operator’s network as well as by your home operator’s network.
- The visited network passes the SMS via dedicated signalling links to your home network.
- Your home network sends the SMS to your friend’s network, which delivers it to your friend’s mobile phone.