| 摘要 |
The method and apparatus relate to a digital telecommunication system in which information is transferred between terminals (T1-Tn) connected to a telephone exchange for establishing a ring with the aid of loop connection to enable sending data between arbitrarly selected terminals. Each of the terminals includes at least one send channel and one receive channel. A telecommunication system of the kind mentioned can, for example, include a plurality of terminals connected via time multiplexed channels to an exchange of the stored program control type (SPC), in which the switching functions are controlled by software. The terminals may consist of telephone sets, display units etc. Control units and separate computers can also be connected to the exchange. In the known art, setting up of communication paths through the exchange is always done in pairs, i.e. send and receive directions between two subscribers are always connected directly to each other. In accordance with the invention, a transfer with the aid of the exchange is made instead, from an arbitrary terminal to the next terminal in a serial loop or ring irrespective of between which terminals connection is desired. The information from a terminal to another thus goes via all terminals connected to the loop. The loop is set up with the aid of the exchange in such a way that the send output (S) of a preceding terminal being connected to the receive input (R) of the next terminal etc. such that a closed ring is obtained, enabling a terminal anywhere within a PABX to be connected to another optional unit. This also applies if the PABX solution is distributed over a large geographical area. |
