DATABASE CONTROL ISSUES: SECURITY, BACKUP AND RECOVERY, CONCURRENCY - Fundamentals of Database Management Systems - page 295

Intercepted
Communications

Supply Chain
Partner
Computer

Company Offices

Computer

Damaging
Hardware Customer

Computer

Computer
Virus

Database

“Hacker”
Computer

“Unauthorized
Access”

Stealing Disks
or Computers

F IGURE 11.1
Data security breaches

Unauthorized Computer Access One method of stealing data is gaining unauthorized
access to a company's computer and its data. This can be accomplished in a variety
of ways. One is by ''hacking'' or gaining access from outside the company. Some
hackers are software experts who can exploit faults in a company's software. Others
use stolen identification names and passwords to enter a computer looking like
legitimate users. Indeed, as we suggested earlier, some data thieves actually are
legitimate users: company employees who have authorized access to the company's
computer system but are intent on stealing data they are authorized to see or
breaking into databases for which they do not have access. In all these cases, data
is ''downloaded'' or copied and used illicitly from then on.

Intercepting Data Communications Intercepting data communications is the computer
version of the old concept of '' wiretapping .'' While data may be well protected
in a company's computers, once it is transmitted outside the company it becomes
subject to being stolen during transmission. Some data transmission media are more
subject to interception than others. Tapping a simple ''twisted-pair'' telephone line
or a coaxial cable takes skill but is feasible. When data is bounced off satellites it
is also subject to interception. On the other hand, the light pulses going fiber-optic
transmission lines cannot be tapped.

Stealing Disks or Computers Can disks or even computers (with data on their hard
drives) be stolen? That would have been difficult years ago when all computers were