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| 3.5 |  | Isolating Physical Layer Problems |
| 3.5.6 |  | Operational statistics |

A variety of end-station and network device commands can be used to gather operational statistics on a network or on specific component links and devices. These commands have been discussed in section 3.3 and also in 3.4.8 which details CPU statistics over time.

Operational statistics can also be gained from centrally located network analysis software or even dedicated hardware. Simple Network Management Protocol (SNMP) can be used to get each SNMP capable network device to report back to a central monitoring host which is loaded with software to interpret input from network devices. Similarly the Network Analysis Module (NAM), designed for Cisco 6500 series devices can become the nerve center for analysis of network function. The NAM stores operational statistics collected using remote VLAN and port centric or local VLAN Switchport Analyzer sessions for each Cisco switching component of the network. The data can then be compared to historical data. Increasing the level of data capture occurring on network operational statistics, a troubleshooter can gain valuable intelligence on a network. This data can be used to isolate network problems and also to identify under resourced or over utilized links and components within the network.