PROLiNK H52201 User Manual - Manual (Page 32)

PROLiNK Hurricane 5200C/5201 ADSL2+ Modem / Router
User Manual
Page 32 of 59
8.7 IGMP PROXY CONFIGURATION
Multicasting is useful when the same data needs to be sent to more than one hosts. Using
multicasting, as opposed to sending the same data to the individual hosts uses less
network bandwidth. The multicast feature also enables you to receive multicast video
stream from multicast servers.
IP hosts use Internet Group Management Protocol (IGMP) to report their multicast group
memberships to neighboring routers. Similarly, multicast routers use IGMP to discover
which of their hosts belong to multicast groups. Hurricane 5200C/5201 supports IGMP
proxy that handles IGMP messages. When enabled, this modem/router acts as a proxy for
a LAN host making requests to join and leave multicast groups, or a multicast router
sending multicast packets to multicast group on the WAN side.
When a host wishes to join a multicast group, it sends IGMP REPORT message to
Hurricane 5200C’s IGMP downstream interface. The proxy sets up a multicast route for the
interface and host requesting the video content. It then forwards the Join to the upstream
multicast router. The multicast IP traffic will then be forwarded to the requesting host. On a
leave, the proxy removes the route and then forwards the leave to the upstream multicast
router.
The IGMP Proxy page allows you to enable multicast on WAN and LAN interfaces. The
LAN interface is always served as a downstream IGMP proxy, and you can configure one
of the available WAN interfaces as the upstream IGMP proxy.
„ Upstream: The interface that IGMP requests from hosts (LAN) is sent to the
multicast router.
„ Downstream: The interface data from the multicast router are sent to hosts (LAN)
in the multicast group database.