| 摘要 |
1. Apparatus (3) for routing telephone calls comprising: input means (130) operable to receive an input signal representative of a user generated call number defining a user selected call destination (2); signal generating means (131) operable to prefix the input signal with a prefix signal representative of a selected prefix code defining at least a network connection route selected from a plurality of available routes to the user selected call destination; memory means (134, 135) operable to store a decision table containing predetermined data for determining prefix codes corresponding to a plurality of respective call destinations; selecting means (133) operable to obtain said selected prefix code corresponding to said user selected call destination by addressing the memory means; output means (132) operable to output an output signal corresponding to the input signal prefixed by the prefix signal; receiving means (137) operable to receive a wireless broadcast signal of updating information, and updating means (136) operable to update the predetermined data stored in the decision table in accordance with the received updating information, wherein the updating means is operable to update the predetermined data in the decision table with updating information including network ID data identifying for a respective call destination a preferred route calculated by a control centre from which the updating information is broadcast in use; and wherein the memory means further includes a network table for obtaining the prefix code from the network ID. 2. Apparatus as claimed in claim 1 wherein the updating information comprises a set of updated predetermined data defining an updated decision table. 3. Apparatus as claimed in any preceding claim wherein the broadcast signal is a radio signal, and the receiving means includes an antenna (9) and receiving circuitry (138). 4. Apparatus as claimed in any preceding claim wherein the memory means includes first and second memory areas operable to store respective first and second decision tables (135, 134), the apparatus further comprising designating means (140) operable to selectively designate only (135) one of said first and second memory areas as an active memory addressable by the selecting means and to designate the remaining one (134) of the memory areas as an inactive memory which is non-addressable by the selecting means, whereby the selecting means is operable to address the decision table in the active memory and the updating means is operable to update the predetermined data stored in the inactive memory, and wherein the designating means is operable to designate as the active memory the memory area for which updating has most recently been completed. 5. Apparatus as claimed in any preceding claim wherein the memory means is further addressable with time period data representative of a time period within which the input signal is received, whereby for each call destination the predetermined data defines a plurality of prefix codes corresponding to a plurality of respective time periods. 6. Apparatus as claimed in claim 5 further comprising clock means (139) operable to provide said time period data to the selection means according to current local time. 7. Apparatus as claimed in claim 6 wherein the updating information includes clock resetting data and wherein the apparatus comprises clock resetting means (136) operable to reset the clock means. 8. Apparatus as claimed in any preceding claim, comprising means (30) for determining the user selected call destination used by the selecting means in addressing the decision table based on the first received digits of the user generated call number. 9. Apparatus as claimed in claim 8, wherein the input means is arranged to store the sequentially received user generated call number digit by digit in a buffer (19) until the selection means has selected the selected prefix code on the basis of the first received digits and until the output means has output an initial portion of the output signal representative of both the prefix code (50, 51, 52) and the stored first received digits, the output means being thereafter operable to output a remaining portion of the output signal representative of sequentially received further digits of the user generated call number without said further digits being stored in the buffer. 10. Apparatus as claimed in any of claims 1 to 8, wherein the input means is operable to store all of the digits (53) of the sequentially received user generated call number in a buffer (19) while the selection means selects the selected prefix code, and the output means is operable thereafter to output the output signal. 11. Apparatus as claimed in any preceding claim wherein the prefix code includes a customer identification field (52) containing user specific identification data. 12. Apparatus as claimed in any preceding claim wherein the prefix code includes a charging information field (51) containing charging information for identifying a control entity to be billed by a network provider corresponding to the selected network connection route. 13. Apparatus (100) as claimed in any preceding claim wherein said input means comprises connection means (13) for connection via an external cable to at least one of a telephone and a facsimile machine to receive said input signal therefrom. 14. Apparatus as claimed in any of claims 1 to 12 formed unitarily with a telephone set (102). 15. Apparatus as claimed in any of claims 1 to 12 formed unitarily with a facsimile device (103). 16. Apparatus as claimed in any preceding claim wherein said receiving means comprises decoding means (138) operable to decode broadcast signals from a pager system transmitter. 17. Apparatus as claimed in claim 16 wherein the receiving means and decoding means are responsive to radio pager transmissions in accordance with the POCSAG standard. 18. Apparatus as claimed in any of claims 1 to 12 formed unitarily with a mobile cellular telephone (120). 19. Apparatus as claimed in claim 18 wherein the receiver is constituted by a receiving circuit (124) of the mobile cellular telephone which further comprises a message handling circuit (121) operable to receive updating information via a message broadcast facility of a cellular telephone system in which the mobile cellular telephone is operable. 20. Apparatus as claimed in any preceding claim comprising detecting means (25) operable to detect whether connection to the user selected call destination has been possible via the selected network connection route in response to the output signal, and default means (S23) operable when such connection is detected not to be possible to output a default output signal defining a default route to the user selected call destination. 21. Apparatus as claimed in any preceding claim wherein the predetermined data defines prefix codes predetermined by a remote entity (7) to provide network connection at minimum cost. 22. A method of controlling routing of telephone calls comprising: collecting route information from a plurality of service providers having respective network connection facilities: compiling a set of preferred routes between call originating terminals and call destinations based on the collected route information; preparing for a group of user terminals in a common geographical area a set of predetermined prefix codes for use in prefixing user generated call numbers to define the preferred network connection routes; broadcasting to the routing apparatus associated with said terminals the predetermined data by means of a wireless broadcast signal; storing the predetermined data in the routing apparatus; and operating the terminals and the routing apparatus in accordance with the predetermined data to make telephone connection between the terminals and the call destinations via the preferred route, wherein the predetermined data prepared at the control centre and broadcast to the routing apparatus comprises network ID data identifying for a respective call destination a preferred route calculated by the control centre; and wherein the routing apparatus obtains the prefix code for routing the telephone connection by using a network table (32) stored in the routing apparatus to obtain the prefix code from the network ID. 23. A method as claimed in claim 22 wherein the preferred routes are determined on the basis of least cost. 24. A method as claimed in any of claims 22 and 23 wherein the wireless broadcast signal is broadcast by a radio pager transmitter, including the step of updating the stored predetermined data by a transmission from the radio pager transmission at a time when pager transmission traffic is off peak. 25. A method as claimed in any of claims 22 to 24 wherein at least one of said service providers is an Internet service provider (152) having Internet connection facilities (150) and wherein at least one of said predetermined prefix codes defines a network connection route via the Internet. 26. A method of operating a radio paging system comprising: transmitting radio paging signals by operation of a transmitter to radio pager devices in accordance with user demands for pager messages; identifying an off peak period in which spare capacity exists in the transmitter operation due to fluctuation in user demand; and transmitting telephone call routing information during an off peak period by operation of the transmitter to telephone call routing devices adapted to receive, store and subsequentially use the call routing information. 27. A control centre (7) for use in controlling the routing of telephone calls comprising: means for collecting route information from a plurality of service providers having respective network connection facilities; means for compiling a set of preferred routes between call originating terminals and call destinations based on the collected route information; means for preparing a set of predetermined p |
