目前,纵横制小交换机的应用在我国比较普遍。但是,近几年来,随着市话事业的发展,各大、中城市相继开办了半自动、全自动接续业务。很多分机用户占上出中继线后,可以直接进行半自动或全自动长途接续,可避开总机话务员的监视,直接将电话拨往外地,甚至拨向国外,给单位带来较沉重的经济负担。鉴于上述情况,服务等级就成为随着市话业务的发展而提出的一个新的服务性能。 At present, the application of crossbar switch is more common in our country. However, in recent years, with the development of the local dialect business, large and medium-sized cities have successively set up semiautomatic and fully automatic splicing businesses. Many extension users account for the trunk, you can direct the semi-automatic or fully automatic long-distance connection, to avoid the operator attendant monitoring directly to the telephone dialed to the field, or even dialed abroad, to bring a heavier economic burden on the unit. In view of the above, the service level has become a new service performance as the local telephone service is developed.