Apparatus and methods using a first service provider such as a WAN cellular service provider to initiate a communications exchange between a plurality of communications units and a second service provider such as WLAN service provider to provide enhanced communications services to the units has been...http://www.google.fr/patents/US20020101858?utm_source=gb-gplus-shareBrevet US20020101858 - Communication services through multiple service providers
Communication services through multiple service providers
Numéro de demande: 09/773,825 Numéro de publication: US 2002/0101858 A1 Date de dépôt: 31 janv. 2001 Brevet délivré: US6879584 ( Date de délivrance 12 avr. 2005)
