The storage of credentials in a central location is referred to as credential management or password vault(PV). Often these tools employ a master credential set (multifactor being preferred) to unlock dataset when needed. Some can even provide auto-login options for apps and websites.
PV offer means to securely store a plethora of credential sets. PVs are often software solutions, sometimes hardware based/local only/cloud storage to generate and store credentials for sites, services, devices, and other secrets. The vault itself is encrypted and must be unlocked to regain access to the stored items. Most PVs use specialized password hashing functions such as PBKDF2 or Bcrypt that add salt and repeat hashing functions many times by key stretching techniques to convert the PVs master password into a reasonably strong encryption key.
Cryptography provides CIA and nonrepudiation(NR) for sensitive info. NR is made possible thru identification and AAAA. It can be established using digital certificates, session identifiers, transaction logs, other transactional and access control mechanisms. NR requires use of PKI cryptosystem.

The OSI layer(s) that best corresponds to the network access layer in the TCP/IP model is the Data Link and Physical Layers. The network access layer in the TCP/IP model is the lowest layer that provides the functions and the mechanisms for accessing and transmitting the data or the information over the physical network or the medium, such as the cable, the wireless, or the optical fiber. The network access layer in the TCP/IP model corresponds to the Data Link and Physical Layers in the OSI model, because they provide similar functions and mechanisms for accessing and transmitting the data or the information over the physical network or the medium, such as:
* The Physical Layer in the OSI model defines and describes the physical characteristics and the specifications of the network or the medium, such as the voltage, the frequency, the modulation, or the connector, and it converts and transmits the data or the information into the electrical, optical, or radio signals, and vice versa.
* The Data Link Layer in the OSI model defines and describes the logical characteristics and the specifications of the network or the medium, such as the addressing, the framing, the error detection, or the flow control, and it establishes and maintains the link or the connection between the systems or the devices, and it transfers and receives the data or the information in the form of the frames or the packets.
The other options are not the OSI layer(s) that best corresponds to the network access layer in the TCP/IP model. The Transport Layer in the OSI model defines and describes the functions and the mechanisms for ensuring the reliable and the efficient delivery and the transmission of the data or the information between the systems or the devices, such as the segmentation, the reassembly, the acknowledgment, or the retransmission, and it corresponds to the Transport Layer in the TCP/IP model. The Application, Presentation, and Session Layers in the OSI model define and describe the functions and the mechanisms for providing the services and the interfaces for the applications or the programs that use the network or the medium, such as the encryption, the compression, the translation, or the synchronization, and they correspond to the Application Layer in the TCP/IP model. The Session and Network Layers in the OSI model define and describe the functions and the mechanisms for establishing and managing the communication and the connection between the systems or the devices, such as the session, the dialogue, the routing, or the addressing, and they correspond to the Internet Layer in the TCP/IP model. References: CISSP All-in-One Exam Guide, Eighth Edition, Chapter 5:
Communication and Network Security, page 535. Official (ISC)2 CISSP CBK Reference, Fifth Edition, Chapter 5: Communication and Network Security, page 536.

Normal outbound traffic has an internal source IP address and an external destination IP address. Traffic with an internal source IP address should only come from an internal interface. Such packets coming from an external interface should be dropped.
Packets with the source-routing option enabled usually indicates a network intrusion attempt.
Router information exchange protocols like RIP and OSPF should be dropped to avoid having
internal routing equipment being reconfigured by external agents.
Source: STREBE, Matthew and PERKINS, Charles, Firewalls 24seven, Sybex 2000, Chapter 10:
The Perfect Firewall.

"publication within the organization" is the goal of the Publication Phase
"write a proposal to management that states the objectives of the policy" is part of Initial and Evaluation Phase "Present the document to an approving body" is part of Approval
Phase.
Reference: TIPTON, Harold F. & KRAUSE, MICKI, Information Security Management
Handbook, 4th Edition, Volume 3, 2002, Auerbach Publications.
Also: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten
Domains of Computer Security, John Wiley & Sons, 2001, Chapter 8: Business Continuity
Planning and Disaster Recovery Planning (page 286).