| 摘要 |
A fax network for communicating fax transmissions over either a conventional public switched telephone network or a digital (frame relay) network based on a telephone number of a destination fax machine. If the destination fax machine can be serviced by the digital network, a faxjack intercepts the phone digits on the telephone link, and redirects the call to a local point-of-presence, which is preferably located near the local exchange carrier. The POP receives information related to the desired fax transmission from the faxjack, and accesses a destination POP via the digital network. The destination POP is local with respect to the destination fax machine, and the destination POP attempts to contact the destination fax machine to ascertain if a fax session is allowable. If so, the destination POP notifies the source POP, which then notifies the faxjack, thereby allowing the fax session to start. The source POP packetizes the analog fax data received from the sending fax machine, and sends the fax data as packets over the digital network to the destination POP. The destination POP unpacketizes the data, and sends the fax data using a standard protocol and a standard local telephone link to the destination fax machine. Each of the POPs also has the capability to spoof the faxjack in order to maintain the fax session. |
