Landline Phone

These services allow cellphone users to send SMS messages to landline phone numbers just as they would to other cellphones. With a representative service, Sprint's Text to Landline, after the customer has sent off the SMS message to the landline number, the recipient's phone rings with the caller ID of the Sprint customer's cellphone. When they pick up, an automated voice reads the text message and allows for a response via a voicemail or via one of a few canned text messages.

Several operators, including BT, Telefonica and Telecom Italia, have true fixed-wire SMS services. These are based on extensions to the ETSI GSM SMS standards and allow fixed-fixed, fixed-mobile and mobile-fixed messaging. These use Frequency-shift keying to transfer the message between the terminal and the SMSC. Terminals are usually DECT-based, but wired handsets and wired text-only (no voice) devices exist. Messages are received by the terminal recognising that the CLI is that of the SMSC and going off-hook silently to receive the message.

When messages are addressed to a device that lacks the ability to receive SMS, then a text-to-speech gateway is employed. The translated message is then either stored in the subscriber's voice mail-box, or the system places a call direct to the end-point and plays the message.