| 摘要 |
PROBLEM TO BE SOLVED: To provide an IP key telephone set which includes an IP outside line function coping with the number of IP outside lines ranging from a small scale to a large scale and a router function, can executes the functions at a high speed and can be achieved at a low cost. SOLUTION: A CCU 1 includes a packet transfer circuit 10 as hardware, and has the IP outside line function and the router function necessary for the IP outside line function. A CEU 2 also includes a packet transfer circuit 20 as hardware, and has the IP outside line function and the router function necessary for the IP outside line function. The CCU 1 and the CEU 2 are connected in series and interlocked to achieve the IP outside line function and the router function of an IP key telephone set as a whole. A basic block of software for controlling the IP outside lines is operated on the CCU 1, and a block for performing NAT of SIP messages, voices and images is operated on the CEU 2. COPYRIGHT: (C)2010,JPO&INPIT |
