Section: Risk, Response and Recovery
Explanation
Explanation/Reference:
In this step, your main objective is to examine and analyze what has occurred and focus on determining the root cause of the incident.
Recovery is incorrect as recovery is about resuming operations or bringing affected systems back into production Containment is incorrect as containment is about reducing the potential impact of an incident.
Triage is incorrect as triage is about determining the seriousness of the incident and filtering out false positives Reference:
Official Guide to the CISSP CBK, pages 700-704

Acceptance confirms that users' needs have been met by the supplied solution.
Verification and Validation informs Acceptance by establishing the evidence-set against acceptance criteria - to determine if the solution meets the users' needs. Acceptance should also explicitly address any integration or interoperability requirements involving other equipment or systems. To enable acceptance every user and system requirement must have a 'testable' characteristic.
Accreditation is the formal acceptance of security, adequacy, authorization for operation and acceptance of existing risk. Accreditation is the formal declaration by a Designated Approving Authority (DAA) that an IS is approved to operate in a particular security mode using a prescribed set of safeguards to an acceptable level of risk.
Certification is the formal testing of security safeguards and assurance is the degree of confidence that the implemented security measures work as intended. The certification is a Comprehensive evaluation of the technical and nontechnical security features of an IS and other safeguards, made in support of the accreditation process, to establish the extent to which a particular design and implementation meets a set of specified ecurity requirements.
Assurance is the descriptions of the measures taken during development and evaluation of the product to assure compliance with the claimed security functionality. For example, an evaluation may require that all source code is kept in a change management system, or that full functional testing is performed. The Common Criteria provides a catalogue of these, and the requirements may vary from one evaluation to the next. The requirements for particular targets or types of products are documented in the Security Targets (ST) and Protection Profiles (PP), respectively.

Network-based IDSs are usually passive devices that listen on a network wire without interfering with the normal operation of a network. Thus, it is usually easy to retrofit a network to include network-based IDSs with minimal effort.
Network-based IDSs are not vulnerable to attacks is not true, even thou network-based IDSs can be made very secure against attack and even made invisible to many attackers they still have to read the packets and sometimes a well crafted packet might exploit or kill your capture engine.
Network-based IDSs are well suited for modern switch-based networks is not true as most switches do not provide universal monitoring ports and this limits the monitoring range of a network-based IDS sensor to a single host. Even when switches provide such monitoring ports, often the single port cannot mirror all traffic traversing the switch.
Most network-based IDSs can automatically indicate whether or not an attack was successful is not true as most network-based IDSs cannot tell whether or not an attack was successful; they can only discern that an attack was initiated. This means that after a network-based IDS detects an attack, administrators must manually investigate each attacked host to determine whether it was indeed penetrated.
Reference:
NIST special publication 800-31 Intrusion Detection System pages 15-16
Official guide to the CISSP CBK. Pages 196 to 197

Packet filtering firewalls use routers with packet filtering rules to grant or deny access based on source address, destination address, and port.
They offer minimum security but at a very low cost, and can be an appropriate choice for a low- risk environment.

Section: Network and Telecommunications
Explanation/Reference:
HTTP is Port 80.
Reference: MAIWALD, Eric, Network Security: A Beginner's Guide, McGraw-Hill/Osborne Media, 2001, page
135.