| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a multicast communication device capable of receiving multicast information from a network interface dedicated to reception. SOLUTION: When a multicast application is started, a terminal 102 that has been moved to a sub network 132 joins a multicast group G at a transmittable I/F, requests a receive-only I/F to join the group G, encapsulates an IGMP(Internet group management protocol) report and transmits the IGMP report to an FA(factory automation) 152 from the transmittable I/F. The FA 152 rewrites the transmission source address of the received IGMP report into its own address and transmits the IGMP report. A multicast routing router 112 that has received the IGMP report performs control so as to construct an information transmission path tree reaching as far as the sub network 132 of the group G. As a result of this, a packet transmitted to the group G by a terminal 101 reaches the multicast application of a terminal 102.</p> |
