Some operator reflects video phone communication is one-way usable. Video phone View Point8220 dials public network terminal and the communication is normal. When it dials private network terminal. one-way communication is usable.
One View Point8220 with public network address connects Quidway NetEngine40 uplink to core Quidway NetEngine40. Another View Point8220 configures private network address and accesses through VPN office network.
Capture packet when public network uses View Point8220 for private network and public network uses View Point8220 for public network. When public network communicates with public network, there are many packets with H.263 protocol. They are sent mutually. The packet is encapsulated video data. When public network and private network communicate, only private network sends H.263 packet and there is no sent H.263 packet. It indicates that View Point8220 itself does not send video data. According to video communication principle, when public network communicates with public network, they will handled by media gateway. And then media gateway sends commands and View Point8220. Here View Point8220 does not send data, it indicates that View Point8220 does not receive commands of media gateway.
Through check the route from View Point8220 to media gateway is not reachable. The route from device to gateway and gatekeeper is different. But it should be the same. Check upper layer device and it is found that NE40 has another accurate route learnt from OSPF. The operator’s MAN device adds such route ip rou 126.96.36.199 255.255.255.255 NULL0 and imports it into OSPF. View Point8220 connected NE40 learns the route through OSPF. Direct route of View Point8220 and media gateway is not reachable. H.263 video data of View Point8220 cannot be sent.
The devica can dial public network terminal, the route is normal. The company office public network is problematic, especially NAT.
When importing OSPF, it should be noticed.