Documentation is essential in today’s increasingly complex networks. It provides vital information
that can greatly reduce network downtime. It also provides verification that the network
is operating correctly.
Baseline information on a network is information about the normal operating conditions of a
network. This baseline is used to determine whether a network configuration is set up in the manner
expected and whether it is operating normally. Some of the specific components of the network
baseline are the network configuration tables, the network topology diagrams, the endsystem
configuration tables, and the end-system topology diagrams.
Network configuration tables show the key configuration parameters that are in place on the
network devices. Some typical items included in a network configuration table are device name,
flash memory DRAM, IOS/CatOS, interface number, MAC address, speed, duplex, VLANs,
trunking, IP address, subnet, subnet mask, and routing protocol. Although these are some of the
standard items in a network configuration table, each table will vary based on a device’s type
and on the design of the particular network. In most cases this information is stored in a spreadsheet
or database format, but hard copies should be regularly printed so that information will
always be available in the event of a problem or failure.
Network topology diagrams are graphical representations of the network components, and
in most cases they contain a subset of the data maintained in the network configuration tables.
The topology diagrams are meant to make the network administrator better able to visualize the
path across the network. Some standard items that go into a network topology are device name,
connections between devices, interface name, VLANs, trunking, IP address, subnet mask, and
routing protocols. As is true for the network configuration tables, hard copies of network topology
diagrams should be regularly printed to ensure that information is always available when
the network goes down.