Iridium Satellite said it plans to offer push-to-talk service to the Department of Defense by the end of the year and to other customers during 2006.

Iridium's P2T solution is designed to let hundreds of users worldwide join a talk group secured by end-to-end encryption. Iridium users wanting to use the P2T service must upgrade their 9505 and 9505A phones with new software and a P2T ancillary device.