UTStarcom iSpirit 3026, Руководство пользователя

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which let the data flow to be transmitted to the backup channel to make sure the device still
works normally. So STP can also avoid a loop when redundancy exists in the network topology.
On one hand, the existence of a loop will bring critical damage to the network; On the other hand,
it is very important to have a backup channel.
1.4.4 ARL table
ARL means Address Resolution Login, it’s the kernel part for transmitting packets in a Layer 2
switch. The iSpirit 3026 switch stores separately for unicast and multicast, named arl and marl
respectively. The hardware searches the arl table and the marl table for the related entry using
the destination MAC address in a data packet, and then outputs the packet to the port identified
by the entry. Table entries can be learned by the switch automatically through data transmission
through input ports, or can be added by network administrators to the arl and marl tables.
1.5 Front Panel
The front panel of the iSpirit 3026 switch have 24 10/100Base-T RJ-45 ports, 2 extendible slots,
ports LED status indicator lights, mode LED indicator lights and mode switches, etc… It’s shown
in Figure1-2.
Figure1-2.The front panel of the iSpirt 3026 switch
1.5.1 10/100Base-T ports
The longest cord length for 10/100Base-T ports is 140 meters. Network devices it can connect
include:
10Base-T compatible devices, such as work stations and concentrators connected
through RJ-45 interfaces using CAT3, CAT4, CAT5 or CAT5E cord;
100Base-TX compatible devices, such as those connected through RJ-45 interfaces