An important step in network design is to examine a customer's existing
network to determine how to meet expectations for network scalability,
performance, and availability. Examining the existing network includes learning
about the topology and physical structure, and assessing the network
performance
.
An
understanding of the existing network structure, uses, and behavior, can be
used to determine whether a customer's design goals are realistic.
Potential problems can be documented. Problems include the identification of
internetworking devices and links that must be replaced because the number of
ports or capacity is insufficient for the new WLAN design. The identification
of performance problems can be helpful in selecting solutions to solve problems
and developing a baseline for future measurements of performance.
Most
network designers do not design networks from the beginning. Instead, they
design enhancements to existing networks. A successful network design requires
the existing network to interoperate with the anticipated wireless inclusion.
Some of the areas of the network to investigate include the LAN
infrastructure and topology. The customer wants to be confident that the
systems engineer (SE) or survey engineer is capable of performing this task.
The SE will need to work with someone in the customer’s IT department to
discover the layout of the customer’s network. Generally, it is a good idea to
begin by identifying the LAN topology. It will be helpful if the customer can
provide a logical drawing of the network.
Network topologies differ
among companies. Most companies use a type of star topology for their network,
such as a clustered or a distributed star. The SE should identify where the
components of the network are located. The IT representative should identify
where the servers are located, where the connectivity points are, and where the
cabling is run throughout the building. In many cases, these locations will be
identified on a network map, which can easily be printed or duplicated. If a
network map does not exist, or is out dated, one must be created.