A network allows a person who does to have physical access to your computer (they are not sitting in front of it) to gain access all the same. If your computer is connected to a network, other people can connect to your computer.
A person who gains unauthorised access to a computer system is often called a hacker.
Preventing Unauthorised Access
For example, by keeping office doors locked.
Use a Username and Have a Good Password
For this to be effective passwords must be chosen that are not easy to guess. Passwords should be a random combination of lowercase letters, uppercase letters and numbers (and symbols if this is allowed):
- ‘Weak’ passwords: password, 123456, david, 27dec1992
- ‘Strong’ passwords: s63gRdd1, G66ew$dQ, gdr298783X
Always Install and Use a Firewall
You can read about firewalls in the Networking Hardware section.
Securing Your Data
The best way to protect data is to encrypt it...
For example, if Alice wants to send important, personal messages to Bob, she must go through the following steps...
The key is usually a very long, random number.
(So maybe Alice will visit Bob and give him a copy of the key on a memory stick or floppy disc).
The encrypted message now looks like a jumble of random letters and numbers.
She can use a public network like the Internet, since, even if it gets stolen, the encrypted message cannot be read or understood without the key.
Bob can now read the original message from Alice.