Cabletron Systems EMM-E6 User Manual

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Using the EMM-E6 Hub View
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Monitoring Hub Performance
General/Error Statistics
The General/Errors statistics windows display the following fields:
Received Bytes
The total number of bytes of data received by this network (channel), module, or 
port since the statistics window was opened or the Reset button was pressed.
Total Packets
The total number of packets of all types received by this network (channel), 
module, or port since the statistics window was opened or the Reset button was 
pressed.
Avg Packet Size
The average number of bytes per packet received by this network (channel), 
module, or port since the statistics window was opened or the Reset button was 
pressed. The average packet size is calculated after each polling interval by 
dividing the cumulative number of bytes received by the cumulative number of 
packets received.
Broadcast Packets
The total number of broadcast packets received by this network (channel), 
module, or port since the statistics window was opened or the Reset button was 
pressed. Broadcast packets have a single address recognized by each station on 
the net: this address is designated in IP form as 255.255.255.255, or in MAC 
hexadecimal form as FF-FF-FF-FF-FF-FF. The ARP and RARP requests sent by 
bridges and routers are broadcast packets.
Multicast Packets
The total number of multicast packets received by this network (channel), 
module, or port since the statistics window was opened or the Reset button was 
pressed. Multicast packets are simultaneously addressed to more than one 
address, but fewer than all addresses.
Collisions 
The total number of collisions recorded by this network (channel), module, or 
port since statistics window was opened or the Reset button was pressed. The 
EMM-E6 counts both receive collisions — those detected while a port is receiving 
data — and transmit collisions — those detected while a port is transmitting data 
(i.e., the port has transmitted one of the colliding packets); however, these counts 
are combined and a single total value is displayed. Collisions of this type (called 
NOTE
Unless you close, then re-open, a window or use the Reset button, statistical counters 
will continue to increment until a value of 2
32
-1 (approximately 4 billion) is reached, at 
which point they will roll over and restart at 0.