Functional Description; Frame Processing; Address Recognition And Filtering - Allied Telesis AT-MS201 Installation Manual

Product Description

Functional Description

The AT-MS201(ST)/202(SC) Micro Switch functions as an unmanaged dual-
port switch or switch without Spanning Tree and Address Aging support.

Frame Processing

The switch supports store and forward switching at Fast Ethernet full-wire
speed either in 10 or 100 Mbps, half or full duplex mode. Packets entering each
port are stored in buffers. After the full packet is received, it is forwarded or
discarded appropriately depending on its destination address and error status.
This ensures that only error-free data packets destined to another segment
will be transferred across the switch, reducing network load. For example, if
the packet entering from Port 1 is destined to an end station on Port 2, it will
be forwarded if the Frame Check Sequence (FCS) is valid. If the packet from
Port 1 is destined to an end station also attached to Port 1, then the packet is
discarded.
The switch will discard CRC error, misaligned, runt, and oversized packets.
When the packet has dribble bits at the end, the switch will truncate to octet
boundary and check for a good FCS before forwarding.

Address Recognition and Filtering

Up to 8,192 MAC addresses can be stored in the MAC address table. The
switch will learn all new addresses in real-time after power-up with its
address self-learning mechanism. If the source address of an incoming packet
is not found in the Address Table, the switch waits until the end of the packet
to check for good CRC and then updates its MAC Address Table. The switch
forwards multicast and broadcast packets and unicast packets when the MAC
address table size is exceeded.
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