Method for interface ISDN private automatic branch exchange and local exchange
View Patent ↗A method for interface an IPABX and a local exchange includes the steps of: processing a call originated from an IPABX by a local exchange having one discernible individual by binding a plurality of data transmission lines, that is, a data transmission line trunk group; and processing a call destined to the IPABX through the local exchange. Since the directory number can be managed by a group name, stepping up from the method for fixing the directory number to the line, the expense for the line can be reduced. In addition, the problem of separation between the origination line and the destination line as in the conventional method that the trunk line and the PRI line are together used is settled. Moreover, since there is no need to allocate an additional signaling point, an expense possibly incurred for the allocation of a signaling point and consumption of the signaling point resource can be prevented.
1. A method for interface of an ISDN private automatic branch exchange (IPABX) and a local exchange, comprising:
processing a first call originated from the IPABX by the local exchange by grouping a plurality of data transmission lines to form a data transmission line trunk group; and
processing a second call destined to the IPABX through the local exchange using the data transmission line trunk group.
2. The method of claim 1 , wherein processing the first call includes:
receiving an external connection code from an IPABX subscriber;
transmitting a set-up message to the local exchange after receiving the external connection code;
checking an origination number of the set-up message received by the local exchange;
receiving and translating a called number if the origination number is effective; and
searching a route sequence corresponding to the translated number and a trunk line to route the first call to a local subscriber or to another exchange.
3. The method of claim 2 , wherein, checking the origination number includes checking whether the origination number is identical to a corresponding pre-digit or checking whether the origination number exists.
4. The method of claim 1 , wherein processing the second call includes:
translating an origination number transmitted from a caller by the local exchange;
searching out a first data transmission line connected to the IPABX, and transmitting a ‘data transmission line occupancy request signal’ to a subscriber service processor (SSP) which manages the plurality of data transmission lines, after translating the origination number;
searching a second data transmission line having an idle channel among the plurality of data transmission lines;
establishing the second call to the IPABX with the second data transmission line; and
transmitting a call notification to a final destination terminal.
5. The method of claim 4 , wherein if a pre-digit of the second call is made with only a prefix, the pre-digit is recognized before the origination number is translated, and a destination occupancy request signal is transmitted to the SSP where a final destination line of the corresponding data transmission line trunk group exists.
6. The method of claim 4 , wherein the idle channel searching is performed by one of a sequential method, a circular method and a random method.
7. The method of claim 1 , wherein at least one data transmission line between the local exchange and the IPABX is operated by a trunk line system.
8. The method of claim 1 , wherein the first call, the second call, or both are distributed while being relayed by a plurality of SSPs.
9. The method of claim 8 , wherein the local exchange makes a database for information on the number of allocated lines in the SSP per data transmission line trunk group, data transmission line trunk group information, SSP line information index per data transmission line trunk group, data transmission line trunk group line information, and pre-digit information, for relaying the first call and the second call to the plurality of SSPs.
10. The method of claim 1 , wherein the local exchange sets a group name of the data transmission line trunk group, as to whether a dial tone is to be provided, a digit transmission method, or a charging system.
11. The method of claim 1 , wherein a pre-digit assigned to the data transmission line trunk group includes a prefix or a prefix plus a part of a subscriber's number.
12. The method of claim 11 , wherein a pre-digit including the prefix plus a part of a subscriber's number can accommodate a general subscriber and the IPABX together.
13. The method of claim 1 , wherein the local exchange can register a plurality of pre-digits for one data transmission line trunk group.
14. The method of claim 1 , wherein the local exchange may set up the first or second call or release the first or second call for each channel of a data transmission line.
15. The method of claim 1 , wherein the data transmission line trunk group does not include a signaling point.
16. An interfacing apparatus between an ISDN private switching system and a local exchange, comprising:
an IPABX for originating and terminating a call through a data transmission line connected to the local exchange;
a plurality of SSPs for controlling each of a plurality of sub-systems for an originated call or a terminated call to be distributed;
a switching and number translation processor (SNP) for translating a prefix of the originated call or the terminated call and performing switching in association with the SSP;
a data transmission line trunk group for being assigned a pre-digit including a prefix or a prefix and a subscriber's number, generated by bundling data transmission lines having a same pre-digit among data transmission lines connecting the local exchange and the IPABX; and
a PRI trunk group database for defining a connection relation of data transmission lines linking the IPABX, SSP and SNP.
17. The apparatus of claim 16 , wherein the data transmission line is operated in a trunk line system.
18. The apparatus of claim 16 , wherein the local exchange can register a plurality of pre-digits for one data transmission line trunk group.
19. The apparatus of claim 16 , wherein the pre-digit made with a prefix plus a part of a subscriber's number can accommodate a general subscriber and the IPABX together.
20. The apparatus of claim 16 , wherein the local exchange sets a group name of a generated data transmission line trunk group, as to whether a dial tone is to be provided, a digit transmission method, or a charging system.
21. The apparatus of claim 16 , wherein the data transmission line trunk group database includes a database of the information on the number of allocated lines in the SSP per data transmission line trunk group, a data transmission line trunk group information database, a SSP line information index database per data transmission line trunk group, a data transmission line trunk group line information database, and a pre-digit information database.