"GEO-Mobile Radio Interface Specifications". Basically these are
standards for satellite phones, roughly analogous to GSM (and much of
GMR is derived from GSM). Much of the spec is available at:
http://www.etsi.org/WebSite/homepage.aspx
The stub article at Wikipedia has more links:
http://en.wikipedia.org/wiki/GEO-Mobile_Radio_Interface
The encryption algorithm (apparently a stream cipher, and apparently
the bit that's been broken) in either version is proprietary and not
one of the publically available bits.