As mobile phones accumulate new applications and become more advanced, OTA configuration has become increasingly important as new updates and services come on stream. OTA via SMS optimises the configuration data updates in SIM cards and handsets and enables the distribution of new software updates to mobile phones or provisioning handsets with the necessary settings with which to access services such as WAP or MMS. OTA messaging provides remote control of mobile phones for service and subscription activation, personalization and programming of a new service for mobile operators and telco third parties.
When OTA is used to update a phone's operating firmware, it is sometimes called "Firmware Over The Air" (FOTA). For service settings, the technology is often known as Device Configuration.
Various standardization bodies were established to help develop, oversee, and manage OTA. One of them is the Open Mobile Alliance (OMA).
The OTA mechanism requires the existing software and hardware of the target device to support the feature, namely the receipt and installation of new software received via the wireless network from the provider.
New software is transferred to the phone, installed, and put into use. It is often necessary to turn the phone off and back on for the new programming to take effect, though many phones will automatically perform this action.
Depending on implementation, OTA software delivery can be initiated upon action, such as a call to the provider's customer support system or other dialable service, or can be performed automatically. Typically it is done via the former method to avoid service disruption at an inconvenient time, but this requires subscribers to manually call the provider. Often, a carrier will send a broadcast SMS text message to all susbcribers (or those using a particular model of phone) asking them to dial a service number to receive a software update.
Verizon Wireless in the U.S. provides a number of OTA functions to its subscribers via the *228 service code. Option 1 updates phone configuration, option 2 updates the PRL. Similarly Voitel Wireless that uses Verizon network uses *22890 service code to program Verizon based Voitel wireless phones. Interop Technologies provides a number of nationwide wireless operators in the US with an SS7 Based Over-the-Air device management solution. This solution allows operators to manage wireless device functionality including renumbering handsets, updating phone settings, applications and subscriber data and adjusting PRL to manage cost structures.
OTA by SMS is not limited to cellular network operators. OTA messages may also be generated by third parties and sent directly to the handset. For example, UK VoIP operator aql uses an OTA configuration message to automatically configure the SIP VoIP client on Nokia's E-Series handsets when users sign up for their mobile VoIP service.
To provision parameters in a mobile device OTA, the device needs to have a provisioning client capable of receiving, processing and setting the parameters. For example, a Device Management client in a device may be capable of receiving and provisioning applications, or connecticity parameters.
In general, the term OTA implies the use of wireless mechanisms to send provisioning data or update packages for firmware or software updates to a mobile device - this is so that the user does not have to go to a store or a service center to have applications provisioned, parameters changed or firmware or software updated. Non-OTA options for a user are a) to go to a store and seek help b) use a PC and a cable to connect to the device and change settings on a device, add software to device, etc.
OTA is similar to firmware distribution methods used by other mass-produced consumer electronics, such as cable modems, which use TFTP as a way to remotely receive new programming, thus reducing the amount of time spent by both the owner and the user of the device on maintenance.