IP-COM G3210P, Руководство пользователя

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Advanced Settings
Tip:
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Each VLAN has a corresponding MAC address table. The same MAC address can be
added into different VLANs.
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The MAC address entry in the Static Address Table cannot be added to the Filtering
Address Table.
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Once VLAN mode is toggled, all current settings will be cleared.
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A certain port in the static MAC address table can receive packets whose source
MAC address matches its corresponding VLAN ID; Packets whose destination MAC
address matches the corresponding VID can only be forwarded to the corresponding
port.
2 STP
The Spanning Tree Protocol (STP) is a network protocol that ensures a loop-free topology
for any bridged Ethernet local area network. The basic function of STP is to prevent bridge
loops and the broadcast radiation that results from them. Spanning tree also allows a
network design to include spare (redundant) links to provide automatic backup paths if an
active link fails, without the danger of bridge loops, or the need for manual
enabling/disabling of these backup links.
Spanning Tree Protocol (STP) is standardized as IEEE 802.1D. As the name suggests, it
creates a spanning tree within a network of connected layer-2 bridges (typically Ethernet
switches), and disables those links that are not part of the spanning tree, leaving a single
active path between any two network nodes.
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STP protocol packets
To implement spanning tree function, switches in the network transfer BPDUs between
each other to exchange information. BPDUs carry the information that is needed for
switches to figure out the spanning tree.
The network topology is determined by BPDU transmission among devices. There are two
types of BPDUs in the original STP specification
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Configuration BPDU: Configuration BPDU (CBPDU), used for Spanning Tree
computation and spanning tree topology maintenance.
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Topology Change Notification (TCN) BPDU, used to announce changes in the
network topology
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Basic concepts of STP
1
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Bridge ID
The bridge ID contains both numbers combined together - Bridge pr MAC, in which