Understanding the network.pdf - Back to Home

Actually, the purpose of network analysis is twofold. First, in order to implement any
effective monitoring and management system, you need to have an understanding
of how your network functions. Your understanding should encompass the
following:
• WAN link and LAN segment bandwidth utilization
• WAN and LAN protocol usage
• Average and peak utilization network response times
• Network traffic flow patterns between segments, gateways, and servers
• Network application services
• Layer 2 and Layer 3 packet statistics
Through the use of network analysis techniques, you can establish a set of network
performance baselines. Network baseline data is used for a variety of network
management-related tasks. For example, when setting up network monitoring,
baseline data is used for setting management and monitoring probe alarms.
Although default values ("norms") for most monitoring variables exist, these might
not always apply to your network environment. By using network baseline data to
set monitoring alarm thresholds, your network management system will be more
effective and provide more useful information.
The second purpose of network analysis is to resolve network fault conditions and to
improve overall network performance through performance tuning. Performance
tuning is making configuration and design adjustments to the network to improve
its performance based on the results of management and analysis data. Again, here
is where network baseline data is helpful. If the network users complain of poor
network performance, without any performance baseline data it is difficult to
pinpoint a cause. Therefore, instead of identifying the actual problem, additional
resources are implemented which might or might not actually fix the problem. There
are some contexts where additional network resources are needed, but
implementing them without identifying the actual problem you are trying to correct
can sometimes make the problem worse. Throwing money at performance
problems is an expensive approach to resolving them. Your approach to network
analysis depends largely on whether you are determining the network's
performance baseline or resolving a network performance or fault condition.
Tools
Although network management systems and vendor-specific GUI-based
configuration tools are the most commonly associated networking tools for network
data collection and diagnostics, they are not the only tools needed to effectively
manage your network. Packet analyzers or packet sniffers, time domain reflectors,
bit error rate testers, and software tools like ping and traceroute are each valuable
tools that you will at some point need in order to resolve a problem on your network.