As part of planning a baseline, the devices and ports of interest must be
identified.
Ports of
interest include those network device ports that connect to other network
devices, servers, key users, and anything else considered critical to the
operation. By narrowing the ports polled, the results will be concise and
network management load will be minimized. Remember that an interface on a
router or switch can be a virtual interface, such as a switch virtual interface
(SVI).

After the ports have been initially identified a method to track and
document future network changes should be established. Without a tracking
method, reports will become inaccurate. A report may indicate that a backbone
port on a particular device is performing fine, when in fact the device
connected to that port is not a router, but a PC, due to an undocumented
change.
One method to track the ports of interest is to use the port
description fields on devices to indicate what is connected. If backbone Router
A is connected to switch port 1/1 on the main campus, the port description on
switch port 1/1 should be configured for the device (Router A) on the other
end. The port description can then be used for adding clarity to the reports
created from the baseline and performance monitoring.