| 摘要 |
A clearinghouse is used to determine caller location for VoIP calls. The clearinghouse maintains (i) a first correlation between a first IP address and a first ISP and (ii) a second correlation between a second IP address and a second ISP. The clearinghouse receives the first IP address from a VoIP service provider (VSP). The first IP address is a source address of a request from a VoIP telephone to set up a call, received by the VSP from the first ISP. The clearinghouse references the first correlation and queries the first ISP with the first IP address. The clearinghouse then receives from the first ISP a location associated with the first IP address. The clearinghouse transmits this location to an entity such as the VSP or, for a 911 call, perhaps a PSAP. The clearinghouse may select the PSAP based at least in part on the location.
|
