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CompTIA A+ Certification All-in-One Exam Guide

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and data encryption. But before anyone encounters the on-network security,

there are some measures we can take to reduce the likelihood our network

will be targeted in the first place. Let’s take a look at these practices first,

followed by the methods for securing the network itself.

SSID

The service set identifier (SSID) parameter—also called the network name—

defines the wireless network. Wireless devices want to be heard, and WAPs

are usually configured to announce their presence by broadcasting the SSID

to their maximum range. This is very handy when you have several wireless

networks in the same area, but a default SSID also gives away important

clues about the manufacturer (and maybe even model) of an access point.

Always change the default SSID to something unique and change the

password right away. Configuring a unique SSID name and password is the

very least that you should do to secure a wireless network. Older default

SSID names and passwords are well known and widely available online.

While newer models may come with unique SSIDs and passwords, the SSID

may still leak information about your hardware—and the generated password

may use rules that make it easy to break.

These defaults are intended to make setting up a wireless network as easy

as possible but can cause problems in places with a lot of overlapping

wireless networks. Keep in mind that each wireless access point in a network

needs to be configured with the same unique SSID name. This SSID name is

then included in the header of every data packet broadcast in the wireless

network’s coverage area. Data packets that lack the correct SSID name in the

header are rejected. When it comes to picking a new unique SSID, it’s still

good to think about whether the name will make your network a more

interesting target, or give away details that could help an attacker gain

physical or remote access.

Another trick often seen in wireless networks is to tell the WAP not to

broadcast the SSID. In theory, people not authorized to access the network

will have a harder time knowing it’s there, as it won’t show up in the list of

nearby networks on most devices.

In practice, even simple wireless scanning programs can discover the

name of an “unknown” wireless network. Disabling the SSID broadcast just

makes it harder for legitimate clients to connect. It doesn’t stop bad actors at

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