| 摘要 |
<p>PROBLEM TO BE SOLVED: To shorter a transfer delay time when quality is revised by sending a packet according to required quality without awaiting a message for reserving a resource when a resource corresponding to the required quality is allowed to reserve. SOLUTION: A transmitter side user terminal equipment 111 sends transmission data of an IP packet to a communication network. Communication modes 121-123 convert a packet into fixed length cells and transfers the cells by ATM communication networks 133, 134 composed of virtual connections 151, 152 or the like set by ATM exchanged 131, 132 or the like. A receiver side user terminal equipment 112 sends a reservation message composed of an RSVP resource reservation protocol to request service quality to the transmitter side user terminal equipment 111. Upon receipt of a reservation message, the communication node, e.g. 122 sets a band width in response to the requested quality to the virtual connection 152. The communication node 122 transfers cells without awaiting an acknowledge of reserving the band width by setting the virtual connection 152 to an ABT/IT service.</p> |
