| 摘要 |
<p>In a system for permitting video telephony, a first client (10) has a first computer (30) including a first microphone and miniature video camera, connected to a first cellular telephone (40). A second client (20) has a second computer (50) including a second microphone and miniature video camera, connected to a second cellular telephone (60). Audiovisual data captured by the first computer (30) are sent via the cellular network to a server (80) which includes a domain name server (DNS). The DNS dynamically allocates an IP address to the first client (10) in dependence upon the telephone number of that client's cellular telephone (40). The telephone number of the second client's telephone (60) is resolved by the DNS if he is connected to the system, otherwise a request for connection is sent to the second client (20). If accepted, a second IP address is allocated to the second client and bidirectional transfer of audiovisual data using the IP protocol can commence via the Internet. <IMAGE></p> |
