| 摘要 |
<p>PURPOSE:To acquire an efficient communication line in a packet exchange network by connecting a call connection request from a terminal equipment to an optional terminal equipment via a termination station of a fixed connection communication line and substituting the selective connection even at a fault of the fixed connection communication line. CONSTITUTION:Packet exchange stations A,B-D are connected mutually via relay lines R1,R2-R4 respectively, a terminal equipment T1 is connected to the station A, a terminal equipment T2 is connected to the station C and a terminal equipment T3 is connected to the station D. Then patterns 1-4 are set by using respectively a fixed connection request signal from the terminal T1 in the fixed connection communication line between the terminal equipment T1 and the stations A-D. When the fixed connection request signal is transmitted from the terminal equipment T1 in the pattern 2, for example, the stations A, B receive it and the communication line with the terminal equipment T1 is set. Then the data transmitted from the terminal equipment T1 is transmitted to the station B and connected selectively to the opposite terminal equipment T2 according to the address information set in the data. If a fault takes place in the relay line R2 between the stations B and C, the station B is connected selectively to the opposite terminal equipment T2 via the relay lines R3 and R4.</p> |
