Accessing Hub Features

Interpreting Device Status

 

Figure 12-4. Hub Global Counters

 

The counters are described in the following table.

 

Table 12-2. Global Counters

 

 

Counter

Description

 

 

Total Packets

Total number of packets (including bad packets, broadcast packets, and multicast

 

packets) received.

Total Octets

Total number of octets of data (including bad packets) received on the network.

 

This object can be used to estimate Ethernet utilization.

Broadcast Packets

Messages sent to all users on the network.

Multicast Packets

Multicast packets are delivered to a subset of users on the network, as opposed

 

to Broadcast packets, which are sent to all users.

 

 

Collisions

When two or more devices attempt to transmit a message on a cable at the same

 

time, interfering with one another's transmissions. The number of collisions

 

should be proportional to the number of packets transmitted over time and the

 

number of nodes operating on the network.

CRC/Alignment Errors

The Cyclic Redundancy Check (CRC) is a code typically placed at the end of the

 

frame or packet to ensure the integrity of the data within the frame.

 

Alignment Errors are the number of instances where the CRC method was used

 

to correct a packet whose bits were misaligned because of timing errors.

Fragments

Total number of packets received that were less than 64 octets in length and had

 

a bad Frame Check Sequence (FCS).

 

 

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