The MA5620G encounters a one way audio fault.. That is, the remote end can hear the subscriber of the MA5620G, but the subscriber of the MA5620G cannot hear the remote end.
1. Voice services of other MDUs in the same network segment of the same OLT are normal, and there is no one way audio when calls are made. This indicates that the fault is not caused by network limitation or quality, or the peer gateway.
2. Check configurations of the MA5620G. It is found that configurations are correct and the broadband service is normal. Compare the faulty MA5620G with a normal one. It is found that the faulty MA5620G is configured with ACL rules and references these ACL rules to the upstream PON port.
rule 5 deny ip
rule 10 permit ip source 222.x.x.18 0
packet-filter inbound ip-group 3001 rule 5 port 0/0/1
packet-filter inbound ip-group 3001 rule 10 port 0/0/1
The normal MA5620Gs are not configured with ACL rules. In this case, the fault may be caused by ACL rules. Therefore, delete the preset ACL rules from the PON port. It is found that the voice service is normal, and one way audio is rectified.
1. The quality of the network is poor.
2. The NAT firewall limits the voice service.
3. The peer gateway is faulty.
4. Configurations of the MA5620G are incorrect.
ACL rules of an optical access device are different from that of a DLSAM.
1. The packet-filter command does not take effect on the packets sent from the CPU or reported to the CPU. But the DSLAM filters packets passing a port.
2. Signalings are sent from the CPU and are not filtered by the upstream port by running the packet-filter command.
3. Media streams are provided by the DSP and are forwarded by the LSW without passing the CPU. In addition, media streams are filtered by the upstream port by running the packet-filter command.
4. The packet-filter command takes effect only for the inbound direction of the LSW.
5. Matching principle of the ACL rules referenced by running the packet-filter command is validity-first and configuration-second.
When ACL rules are configured on an optical access device, if the ACL rules are referenced to the upstream port, the device management packets and signalings are not limited, but the media streams are filtered. In this case, be cautions to configure ACL rules.