| 摘要 |
<p>PROBLEM TO BE SOLVED: To utilize an empty band on an ATM transmission line and to perform a high quality sound transmission in accordance with the number of sound line by a sound compression part's executing a sound compression processing that is altered by a changeover signal from two farm wares and a cell/decell control part for performing a sound encoding system different in the rage of compression. SOLUTION: When a transmission cell is over a maximum transmission capacity and a rejection cell is generated, a congestion information CLP is added to a cell header of a line that occupies the same passage from an ATM network. This congestion information CLP is received by a cell/decell control part 3b of a station B and a line of its passage detects an occurrence of congestion. Then, a line of a passage where congestion of the station B occurs detects a precedence information field of a cell being transmitted to a station A from the control part 3b. If the line is the one of '0' precedence, a low speed changeover request information is added to a changeover request field and a cell that requires a changeover to 8 KzCS-ACELP is transmitted to a station A.</p> |
