Zte ZXDSL 9210 (V3.1), Техническое руководство

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2-5
different VLANs are identified, and the whole-network VLAN interconnection
is possible.
3. Supports the PVLAN mode
Private VLAN (PVLAN) consists of two kinds of ports: Normal VLAN ports
and PVLAN ports. Normal ports may interwork with all same VLAN ports
while a PVLAN port can only interwork with normal ports instead of any other
PVLAN port.
PVLAN ports refer to those ports in PVLAN which cannot interwork with each
other. They are generally used as user ports in actual applications.
Normal ports refer to those ports in PVLAN which can interwork normally with
other ports. They are generally used as uplink ports in actual applications.
2.1.3.4 Multicast Service
Multicast aims to reduce redundant data and save bandwidth. It transmits the same
information to multiple positions at almost the same time. The ZXDSL 9210 (V3.1)
equipment supports the IGMP SNOOPING protocol.
The IGMP Snooping protocol manages and controls multicast groups, and employs the
IGMP messages. IGMP Snooping runs at the link layer. When receiving any IGMP
message transferred between the host and the router, a Layer 2 device will copy it and
transfer it to the CPU. Then, the IGMP Snooping analyzes the information contained in
the IGMP message, and establishes and maintains a MAC multicast address table at
Layer 2. The future multicast messages sent from the router will be forwarded
according to the MAC multicast address table. The IGMP Snooping sends an IGMP
message initiatively to the port only when it has received the “IGMP going offline”
message or the “Aging timer timeout” message from a certain port. Both these
messages are for querying a specific IGMP group. Otherwise, it will not send any
message to the port.
2.1.3.5 Broadband O&M System
The “O&M system” of ZXDSL 9210 (V3.1) consists of three parts: xDSL line test
system, Modem remote management, and M + 1 protection.
1. xDSL line test system