Transparent transmission of multicast data for private-line users
Transparent transmission of IGMP messages
In the upstream direction, the service board determines whether to transparently transmit the received IGMP messages according to the VLAN-level IGMP transparent transmission policy and service-port-level transparent transmission policy. If transparent transmission is allowed, IGMP messages are added with the SVLAN tag on the service board and then are transmitted to the control board. After arriving at the control board, IGMP messages are broadcast by the control board within the SVLAN. If transparent transmission is not allowed, IGMP messages are dropped.

In the downstream direction, the IGMP messages transmitted from the network side are broadcast by the control board within the SVLAN and after they arrive at the service board, the service board determines whether to transparently transmit them according to the VLAN-level IGMP transparent transmission policy and service-port-level transparent transmission policy. If transparent transmission is allowed, the service board translates the SVLAN tag to the CLAN tag according to the configuration of the traffic stream and then transmits the messages to users. If transparent transmission is not allowed, IGMP messages are dropped.

Transparent transmission of unknown multicast data
In the upstream direction, the service board determines whether to transparently transmit the received unknown multicast data according to the VLAN-level IGMP transparent transmission policy and service-port-level transparent transmission policy. If transparent transmission is allowed, IGMP messages are added with the SVLAN tag on the service board and then are transmitted to the control board. After arriving at the control board, IGMP messages are broadcast by the control board within the SVLAN. If transparent transmission is not allowed, IGMP messages are dropped.

In the downstream direction, the unknown multicast data transmitted from the network side is broadcast by the control board within the SVLAN and after the data arrives at the service board, the service board determines whether to transparently transmit the data according to the VLAN-level IGMP transparent transmission policy and service-port-level transparent transmission policy. If transparent transmission is allowed, the service board translates the SVLAN tag to the CLAN tag according to the configuration of the traffic stream and then transmits the data to users. If transparent transmission is not allowed, unknown multicast data is dropped.

NOTE:
To prevent the multicast data of the multicast user provisioned with multicast service from being transmitted to the upstream unauthorized multicast sources, make sure that the policy of transmitting unknown multicast data is set to drop. The transparent transmission policies of unknown multicast traffic have the switches of two levels on a service board: the VLAN level and the service port level. When the two switches are both set to transparent transmission, the policy is transparent transmission. When either of the two switches is set to drop, the policy is drop. (Only transparent transmission is supported for connection-oriented traffic and the policy is not configurable in this case.)

Co-existence of IPTV service and transparent transmission of multicast data
Multi-service-port solution
IPTV service and multicast transparent transmission service are carried on two service ports, and the SVLAN of the service port that carries multicast transparent transmission service must not be the MVLAN.

The service port that carries IPTV service processes the received IGMP messages following the flow of processing IPTV service, and forwards the multicast data according to the multicast forwarding entry.

The service port that carries multicast transparent transmission service transparently transmits or drops the received IGMP messages according to the IGMP transparent transmission policy of the traffic stream, and transmits or drops the received unknown multicast data according to the unknown multicast transparent transmission policy of the traffic stream.

Single-service-port solution
IPTV service and multicast transparent transmission service are carried on one service port, whose SVLAN must not be the MVLAN.

When the Access Node receives upstream IGMP messages, it matches the multicast group address in IGMP messages to the programs in the MVLAN. If the group address successfully matches a program, the Access Node processes the messages as IPTV service. If the group address fails to match any program, the Access Node determines whether to transparently transmit the messages according to the IGMP transparent transmission policy of the SVLAN and service port. The Access Node transparently transmits the messages only when the IGMP transparent transmission policy is enabled for both the SVLAN and service port.

If the Access Node receives downstream IGMP messages that carry the MVLAN tag, the Access Node processes the IGMP messages as IPTV service. If the messages carry the SVLAN tag, the Access Node forwards them according to the IGMP transparent transmission policy of the SVLAN and service port. The Access Node transparently transmits the messages only when the IGMP transparent transmission policy is enabled for both the SVLAN and service port.

If the Access Node receives the multicast data of IPTV service, the Access Node forwards the multicast data according to the multicast forwarding entry. If the multicast data is unknown, the Access Node forwards the data according to the unknown multicast transparent transmission policy of the VLAN and service port. The Access Node transparently transmits the data only when the unknown multicast transparent transmission policy is enabled for both the SVLAN and service port.
Our company supply a large of Huawei OSN 3500, MA5683T.