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EtherWAN Managed Switch Users Guide
SWITCHING
Bridging
To learn MAC addresses, a switch reads all packets that it detects on the LAN or on the
local VLAN, looking for MAC addresses of sending nodes. It places these addresses into its
Ethernet Switching table, along with the interface on which the traffic was received and the
time when the address was learned. When the switch receives traffic on an interface, it
searches the Ethernet switching table for the MAC address of the destination. If the MAC
address is not found, the traffic is flooded out all of the other interfaces associated with the
VLAN. If traffic is received on an interface that is associated with VLAN 1 and there is no
entry in the Ethernet switching table for VLAN 1, then the traffic is flooded to all access and
trunk interfaces that are members of VLAN 1.
Flooding allows the switch to learn about destinations that are not yet in its Ethernet
switching table. If a certain destination MAC address is not in the Ethernet switching table,
the switch floods the traffic to all interfaces except the interface on which it was received.
When the destination node receives the flooded traffic, it sends an acknowledgment packet
back to the switch, allowing the switch to learn the MAC address of the node and to add the
address to its Ethernet switching table.
The switch uses a process called aging to keep the Ethernet switching table current. For
each MAC address in the Ethernet switching table, the switch records a timestamp of when
the information about the network node was learned. Each time the switch detects traffic
from a MAC address that is in its Ethernet switching table, it updates the timestamp of that
MAC address. A timer on the switch periodically checks the timestamp, and if it is older than
the value set for
mac-table-aging-time
, the switch removes the node's MAC address from
the Ethernet switching table. This aging process ensures that the switch tracks only active
MAC addresses on the network and that it is able to flush out from the Ethernet switching
table MAC addresses that are no longer available.
The user can configure:
How long MAC addresses remain in the Ethernet switching table
Add a MAC address permanently to the switching table
Prevent a MAC address from ever being registered in the switching table.
To navigate to the
Bridging
page:
1. Click on the
+
next to
Switching
.
2. Click on
Bridging.
Summary of Contents for EX72129A
Page 27: ...27 EtherWAN Managed Switch Users Guide Figure 3 System Information...
Page 31: ...31 EtherWAN Managed Switch Users Guide Figure 5 IP Address...
Page 55: ...55 EtherWAN Managed Switch Users Guide Figure 13 User Privilege Page...
Page 63: ...63 EtherWAN Managed Switch Users Guide Figure 16 Remote Logging Page...
Page 84: ...84 EtherWAN Managed Switch Users Guide Figure 27 Bridging...
Page 99: ...99 EtherWAN Managed Switch Users Guide Figure 41 PoE Port Setting...
Page 101: ...101 EtherWAN Managed Switch Users Guide Figure 43 PoE Power Scheduling...
Page 122: ...122 EtherWAN Managed Switch Users Guide Figure 45 Port Trunking Version 2...
Page 124: ...124 EtherWAN Managed Switch Users Guide Figure 46 LACP Trunking Version 1...
Page 126: ...126 EtherWAN Managed Switch Users Guide Figure 47 LACP Trunking Version 2...
Page 131: ...131 EtherWAN Managed Switch Users Guide Figure 48 STP Ring Global Configuration...
Page 133: ...133 EtherWAN Managed Switch Users Guide Figure 50 Bridge ID Display...
Page 135: ...135 EtherWAN Managed Switch Users Guide Figure 51 Max Age Hello Timer Forward Delay...
Page 144: ...144 EtherWAN Managed Switch Users Guide Figure 55 Enabling MSTP...
Page 146: ...146 EtherWAN Managed Switch Users Guide Figure 57 Bridge ID Display...
Page 155: ...155 EtherWAN Managed Switch Users Guide Figure 64 Port Cost Priority...
Page 163: ...163 EtherWAN Managed Switch Users Guide Figure 67 Ring Settings...
Page 196: ...196 EtherWAN Managed Switch Users Guide Figure 85 Enabling QoS...
Page 212: ...212 EtherWAN Managed Switch Users Guide Figure 101 Removing a Policy Map...
Page 224: ...224 EtherWAN Managed Switch Users Guide Figure 104 SNMP General Settings...
Page 242: ...242 EtherWAN Managed Switch Users Guide Figure 117 LLDP Global Settings...
Page 244: ...244 EtherWAN Managed Switch Users Guide Figure 118 LLDP Ports Settings...
Page 281: ...281 EtherWAN Managed Switch Users Guide Figure 136 Daylight Savings Date Mode...
