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ESR Series Routers Operation Manual
2.2.2
Functions for MAC address processing
Table 2.2 lists MAC address processing functions of the device
Table 2.2
—
MAC address processing functions
MAC address
table
MAC address table sets the correspondence between MAC addresses and device
interfaces and is used for data packet routing. Routers support table capacity up to
16K of MAC addresses and reserve specific MAC addresses for the system use.
Learning mode
MAC address table may contain either static addresses or addresses learnt during
data packet transition through the device.
Learning involves registration of packet source MAC addresses with their binding
to ports and VLANs. Afterwards, this data is used for incoming packet routing.
Registered MAC address lifetime is limited. Administrator may adjust this setting.
If destination MAC address specified in the packet that was received by the device
is not listed in the table, this packet will be sent further as a broadcast packet
within L2 segment of the network.
2.2.3
Second-layer functions of OSI model
Table 2.3 lists second-layer functions and special aspects (OSI Layer 2).
Table 2.3
—
Second-layer functions description (OSI Layer 2)
VLAN support
VLAN (Virtual Local Area Network) is a solution used for splitting a network into
separate segments on L2 level. VLAN utilization allows to increase the operation
stability for large networks by splitting them into smaller networks, isolate
diversified data traffic by type and solve many other tasks.
Routers support various VLAN management methods:
–
VLAN based on data packet tagging according to IEEE802.1Q
–
VLAN based on device ports (port-based)
–
VLAN based on utilization of data classification policies (policy-based)
Spanning Tree Protocol
(STP)
1
The main task of Spanning Tree Protocol is to exclude redundant network links and
convert network topology into the tree-like structure. Common areas of protocol
application involve the prevention of network traffic loops and establishing of
redundant communication links.
1
In the current firmware version, this functionality is supported only by ESR-1000 router.
