Security Solutions

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Customer Needs Assessment
Vulnerability to Attacks
All networks need protection from malware, but your particular vulnerabili-
ties depend to a certain degree on your environment. As you probably noticed
in the descriptions above, users are often implicated in introducing mal-
ware—even if they do so unintentionally. If possible, you should meet with
users and discuss how they use the Internet.
Then consider questions such as these: Are users free to browse the Internet
and download software? Do they need to do so for their jobs? Does your
company have policies regulating use of the Internet? If so, how does it enforce
them? Does the network have content filtering software, or does the company
rely on voluntary compliance? Does your network access control solution
need to support the policies?
The answers to these questions are also relevant to your plans for implement-
ing protections. For example, you might decide that the only way to ensure
that endpoints are reasonably protected against malware is to implement an
endpoint integrity solution.
Viruses and Worms
Viruses and worms can spread rampant through an unprotected network and
cause enormous amounts of damage to vital files and network resources.
Viruses. Viruses are bits of programming code that require a computer file
to act as a host. Viruses spread by inserting copies of themselves into as many
host files as possible, and they spread to other computers when an infected
file is transferred.
Virus code usually includes instructions for destroying programs and docu-
ments on a hard drive. For example, a virus may insert itself into a required
executable file and spread itself to other files as they open. Then, whenever
an infected file is opened, the virus executes a part of its code that erases large
portions of the endpoint’s memory. If spread to a server, viruses can damage
network software and resources while infecting crucial files.
Worms. Unlike viruses, worms do not require computer files to act as their
hosts. Worms propagate themselves by taking advantage of an infected com-
puter's ability to send data such as an email application over a network. For
example, a worm will often send itself as an email attachment. When the
receiving user opens the attachment, the worm is run as an executable and
infects the receiving endpoint.