| 摘要 |
PURPOSE:To reduce synthetically the cost for a connection channel ineffectively occupies until a conference is held by comparing each connecting distance as far as every participent, and calling participants successively starting from a participation at the shortest distance. CONSTITUTION:When the time of starting a conference is reached, a connecting control circuit 6 compares the charging units ra-rk accumulated in charging registers 101-10n, extracts participent's telephone number NM1 from a telephone number register 71 corresponding to the most inexpensive charging unit, calls participator 51 via a trunk exchange 3 and an exchange network 2, when the participator 51 answers the line is connected to conference trunk 4 and the holding sound is returned to the participant. The same operation as the above is repeated to call participators in order descending in charging unit from and to have participators listen the holding sound. At last, the participator to be charged with the highest charging unit is called, and obtaining answer, the inviter 1 and all the participators are connected to a time switch 8 and a voice bridge circuit 9 to have them start the conference and to have the system start charging. |
