ELTEX ESR Series, Руководство пользователя

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ESR-Series. User manual
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2.2 Functions
2.2.1 Interface functions
Table 1 lists interface functions of the device.
Table 1 – Device interface functions
Cable connection polarity detection
(Auto MDI/MDIX)
Automatic cable type detection–crossed or straight.
MDI (Medium Dependent Interface – straight) – cable
standard for connection of terminal devices;
MDIX (Medium Dependent Interface with Crossover –
crossed) – cable standard for connection of hubs and
switches.
Back Pressure
The backpressure routing method is utilized in half-duplex
connections for management of data streams, coming from the
opposite devices, by means of collisions. This method allows to avoid
buffer overruns and the loss of data.
Flow control
(IEEE 802.3X) Flow control allows to interconnect the low-speed and the high-speed
devices. To avoid buffer overrun, the low-speed device gains the ability
to send PAUSE packets, that will force the high-speed device to pause
the packet transmission.
(LAG, Link aggregation)
Link aggregation allows to increase the communication link
bandwidth and robustness.
Router supports static and dynamic link aggregation. For dynamic
aggregation, link group management is performed via LACP protocol.
2.2.2 MAC table functions
Table 2 lists MAC address processing functions of the device.
Table 2 – MAC address processing functions
MAC 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 128K 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.