Debugging provides the basis for the programmer to correct the logic errors in a
program under development before it goes into production.
Source: Information Systems Audit and Control Association, Certified Information Systems Auditor
2002 review manual, chapter 6: Business Application System Development, Acquisition,
Implementation and Maintenance (page 298).

The following are incorrect answers because they are all suitable methods.
A Delta CRL is a CRL that only provides information about certificates whose statuses have
changed since the issuance of a specific, previously issued CRL.
The Online Certificate Status Protocol (OCSP) is an Internet protocol used for obtaining the
revocation status of an X.509 digital certificate.
A Distribution point CRL or CRL Distribution Point, a location specified in the CRL Distribution
Point (CRL DP) X.509, version 3, certificate extension when the certificate is issued.
References: RFC 2459: Internet X.509 Public Key Infrastru http://csrc.nist.gov/groups/ST/crypto_apps_infra/documents/sliding_window.pdf http://www.ipswitch.eu/online_certificate_status_protocol_en.html
Computer Security Handbook By Seymour Bosworth, Arthur E. Hutt, Michel E. Kabay http://books.google.com/books?id=rCx5OfSFUPkC&printsec=frontcover&dq=Computer+Security+ Handbook#PRA6-PA4,M1

Section: Security Operations

Most stateful packet inspection firewalls work at the network or transport layers. For
the TCP/IP protcol, this allows the firewall to make decisions both on IP addresses, protocols and
TCP/UDP port numbers
Application layer is incorrect. This is too high in the OSI stack for this type of firewall.
Inspection layer is incorrect. There is no such layer in the OSI stack.
"Data link layer" is incorrect. This is too low in the OSI stack for this type of firewall.
References:
CBK, p. 466
AIO3, pp. 485 - 486