A system and method for providing telephony services, such as caller ID, voice mail, selective call forwarding, and the like, to a remote subscriber, typically located outside the provider's regional territory. The system can include customer premise equipment (CPE) selectively connectable to a remote...http://www.google.com.hk/patents/US6411704?utm_source=gb-gplus-share專利 US6411704 - System and method for providing telephony services to remote subscribers
