Firewalls tend to give a false sense of security. They can be very hard to bypass but they need to be properly configured. The complexity of configuration rules can introduce a vulnerability when the person responsible for its configuration does not fully understand all possible options and switches. Denial of service attacks mainly concerns availability. Source: HARRIS, Shon, All-In-One CISSP Certification Exam Guide, McGraw-Hill/Osborne, 2002, Chapter 3: Telecommunications and Network Security (page 412).

Explanation/Reference:
Explanation:
Computer-generated evidence normally falls under the category of hearsay evidence, or second-hand evidence, because it cannot be proven accurate and reliable. Under the U.S. Federal Rules of Evidence, hearsay evidence is generally not admissible in court. Best evidence is original or primary evidence rather than a copy or duplicate of the evidence. It does not apply to computer-generated evidence. Direct evidence is oral testimony by witness. Demonstrative evidence is used to aid the jury (models, illustrations, charts).
References: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 9: Law, Investigation, and Ethics (page 310).
ROTHKE, Ben, CISSP CBK Review presentation on domain 9.

This is another matter of common sense, the CISSP exam has many situations like this. Its not a good practice to have Permanent documents in your e-mail, this is because you don't know if your -mail is always backed up, and maybe the document must be available in a corporate repository. There is not problem to have Copies, draft or temporary documents in your e-mail. The important ones for the company are the
Permanent documents.

Section: Mixed questions