One morning, the computers at U.S. Leasing became sluggish. Computer operators were relieved when a software troubleshooter from IBM called several hours later. They were more than happy to let the troubleshooter help them correct the problem. The troubleshooter asked for a phone number for the computers as well as a logon number and password. The next morning, the situation worsened. A call to IBM confirmed U.S. Leasing's suspicionsomeone had impersonated an IBM troubleshooter to gain unauthorized access to the company's system and destroy the database. U.S. Leasing was also concerned that the intruder had devised a program that would let him access the system again even after all of the passwords were changed. Answer the following questions: What are the possible system weaknesses at U.S. Leasing that allowed the imposter to penetrate its internal security system? What techniques might the imposter have employed to breach U.S. Leasing's network? How can U.S. Leasing avoid these types of incidents in the future?