[ Thanks to S.Ramaswamy for this link.
]
“Networks are funny places where all sort of things happen in a
matter of microseconds. Domain name service lookups are answered,
and data blocks traverse the network as part of file-sharing
protocols (such as SMB and NFS) while packets make their way from
the Internet to your web browser. At any moment a network printer
could go haywire and start broadcasting an endless stream of
address resolution requests, or an NFS client could send mangled
data to its server wreaking havoc on your work.”
“If you’ve done any systems administration work, you have
probably seen these problems and dozen of others. Debugging them
requires experience, as well as the right tools to diagnose what
has gone wrong and to help determine what to do about it.”
“One of the most valuable tools in diagnosing a network
problem, besides the manuals that come with all of your networking
gear, is a network protocol analyzer.”