Application firewalls target Layer 7 of the OSI. The main advantage of an application firewall is its ability to understand specific applications and protocols. Packets are not decrypted until Layer 6, so Layer 7 can see the entire packet. Other firewalls can only inspect the packet, not the payload. It can detect if an unwanted application or service is trying to bypass the firewall by using a protocol on an allowed port, or if the protocol is being used in a malicious manner.

Each IPSec VPN device will have at least one security association (SA) for each secure connection it uses; the SA, which is critical to the IPSec architecture, is the device’s need to support IPSec connections over VPN connections This is a record of the configuration that needs to be in place.

War Dialing is the indiscriminate and repeated act of cracking dial-ups in search of dial-up lines, such as those for non-public internal networks. It automatically scans a list of telephone numbers, usually dialing all numbers in the local area code, and searches modems, computers, bulletin board systems, and fax machines.

〇：IP Session Restriction via Media Gateway

The VoIP Media Gateway translates Internet Protocol (VoIP) voice over time division multiplexing (TDM) voice to and from. As a security measure, the number of calls through the Media Gateway should be limited. The Media Gateway is vulnerable to denial-of-service attacks, hijacking, and other types of attacks.

×：Identification of Rogue Devices  

Incorrect, as rogue devices on both IP telephony and data networks need to be identified.

×：Implementation of Authentication

Incorrect because authentication is recommended for both data and voice networks.

×：Encryption of packets containing sensitive information

Incorrect because sensitive data can be transmitted over either voice or data networks and must be encrypted in both cases. Eavesdropping is a very real threat for VoIP networks.

Sender Policy Framework (SPF) is an email verification system that detects email spoofing and prevents spam and malicious email. Attackers typically spoof e-mail addresses to make recipients believe that the messages come from a known and trusted source. SPF allows network administrators to specify which hosts can send mail from a particular domain by implementing SPF records in the Domain Name System (DNS). The e-mail server is configured to check with the DNS server to ensure that e-mail sent from a particular domain was sent from an IP address authorized by the administrator of the sending domain.

Ethernet is a way of communication used for local area networks; LANs and such communicate over Ethernet. In other words, most communication is now done over Ethernet.

Circuit switching is a dedicated communication channel through a network. The circuit guarantees full bandwidth. The circuit functions as if the nodes were physically connected by cables.

〇：VLAN

Virtual LANs (VLANs) allow logical isolation and grouping of computers based on resource requirements, security, or business needs, despite the standard physical location of the system. Computers in the same department configured on the same VLAN network can all receive the same broadcast messages, allowing all users to access the same types of resources regardless of their physical location.

×：Open Network Architecture  

Open network architecture is wrong because it describes the technology that can configure a network; the OSI model provides a framework for developing products that operate within an open network architecture.

×：Intranet

Incorrect because an intranet is a private network used by a company when it wants to use Internet and Web-based technologies in its internal network.

×：VAN  

Incorrect because a Value Added Network (VAN) is an electronic data interchange (EDI) infrastructure developed and maintained by a service bureau.

Matrix is not a network topology. Ring, mesh, and star are network topologies.

IEEE 802.11 is one of the wireless LAN standards established by IEEE.

〇：How routers are centrally managed and control packets based on the controller’s instructions 

Software-defined networks (SDN) are intended to facilitate centralized management of routing decisions and to separate the router’s logical functions of passing data between the routing decision and the interface and making its mechanical functions.SDN architecture is a scalable, a programmable, and is intended to be a standard method of providing router control logic. Therefore, the correct answer is “a way for routers to be centrally managed and control packets based on the controller’s instructions.

×：Mapping between MAC and IP addresses.

ARP table.

×：Updating the routing table in a dynamic way.

Explanation of dynamic routing.

×：A method in which routers communicate with each other to update the routing table when an event occurs.

This is an explanation of routing control in case of communication failure.

〇：3-tier architecture

The 3-tier architecture clearly distinguishes the three layers: the client has the user interface responsible for input and displaying results, and the server has the functional process logic responsible for data processing and data storage for accessing the database. The user interface role is generally handled by the front-end web server with which the user interacts. It can handle both static and cached dynamic content. The functional process logic is where requests are reformatted and processed. It is typically a dynamic content processing and generation level application server. Data storage is where sensitive data is held. It is the back-end database and holds both the data and the database management system software used to manage and provide access to the data.

×：2-tier architecture

Two-tier, or client/server, is incorrect because it describes an architecture in which a server serves one or more clients that request those services.

×：Screened Subnets

A screen-subnet architecture is for one firewall to protect one server (basically a one-tier architecture). The external, public-side firewall monitors requests from untrusted networks like the Internet. If one layer, the only firewall, is compromised, an attacker can access sensitive data residing on the server with relative ease.

×：Public and Private DNS Zones

Separating DNS servers into public and private servers provides protection, but this is not the actual architecture.

〇：Unified Threat Management

Unified Threat Management (UTM) appliance products have been developed to provide firewall, malware, spam, IDS / IPS, content filtering, data leak prevention, VPN capabilities, and continuous monitoring and reporting in computer networks.

Since this question asks for a definition of Unified Threat Management that is unfamiliar or not even mentioned in the course material, it is inefficient to buy and study a new book just to get this score. To avoid ending up with “I don’t know = I can’t solve it,” be sure to develop the habit of choosing a “better answer.

If you think in terms of the classification Concepts/Standards > Solutions/Implementation Methods, ISCM (NIST SP800-137) and centralized access control systems are the former, while Unified Threat Management and cloud-based security solutions are the latter. Therefore, it is still better to bet on unified threat management and cloud-based security solutions.

×：ISCM (NIST SP800-137)

Because continuous monitoring in the security industry is most commonly Information Security Continuous Monitoring ISCM (NIST SP800-137), which enables companies to gain situational awareness, continuous awareness of information security, vulnerabilities, and threats to support business risk management decisions , is incorrect.

×：Centralized Access Control System

Wrong because a centralized access control system does not attempt to combine all of the security products and capabilities mentioned in the issue. A centralized access control system is used so that its access control can be enforced in a standardized manner across different systems in a network environment.

×：Cloud-based security solutions

Cloud-based security solutions include security managed services that allow an outsourced company to manage and maintain a company’s security devices and solutions, but this is not considered a cloud-based solution. The cloud-based solution provides the infrastructure environment, platform, or application to the customer so that the customer does not have to spend time and money maintaining these items themselves.

The data link layer or Layer 2 of the OSI model adds a header and trailer to the packet to prepare the packet in binary format in local area network or wide area network technology for proper line transmission. Layer 2 is divided into two functional sublayers. The upper sublayer is logical link control (LLC), which is defined in the IEEE 802.2 specification. It communicates with the network layer above the data link layer. Below the LLC is the Media Access Control (MAC) sublayer, which specifies interfaces with the protocol requirements of the physical layer.

〇：TLS is an open community version of SSL.

Secure Sockets Layer (SSL) and Transport Layer Security (TLS) are cryptographic protocols used to protect communications by encrypting segments of a network connection. SSL is a proprietary protocol and TLS was developed by a standards body, making it an open community protocol.

×：TLS is an open community version of SSL. SSL is a proprietary protocol and TLS was developed by a standards body, making it an open community protocol. x: The SSL protocol can be modified by developers to extend its capabilities.

This is incorrect because SSL is a proprietary protocol developed by Netscape. This means that the technical community cannot easily interoperate and extend SSL to extend to its functionality.

×：SSL is an open community protocol while TLS is a proprietary protocol.

The meaning and matching are reversed.

×：SSL is an extended version and backward compatible with TLS.

Wrong, since TLS is actually more extensible than SSL and is not backward compatible with SSL.

〇：For early detection or enclosure in the event of an attack.

Attackers will conduct an investigation before launching a substantial attack. In such cases, a vulnerable network can provide preventative information such as where the attacker is accessing the network from. This is because only an attacker would have the incentive to break into the network. Vulnerable network domains, such as honeypots, make this kind of intrusion easier and clarify the attacker’s behavior. Thus, the correct answer is “to detect or enclose them early in the event of an attack.” will be

×：Debugging environment for when a system outage occurs in the current environment.

The answer is not to intentionally create a vulnerable environment. It is only the result of creating an environment that is vulnerable.

×：Aiming to prevent regressions due to old vulnerabilities.

Even if it is an old vulnerability, it should be addressed and there is no point in allowing it to remain.

×：A special environment for running a product with a low version that is no longer supported.

It is not an answer to intentionally create a vulnerable environment. It is merely the result of creating an environment that is vulnerable.

There are many different types of distributed denial of service (DDoS) attacks; there is no IPSec flood; UDP flood, SYN flood, and MAC flood are all distributed denial of service (DDoS) attacks.

〇：OSI reference model

The OSI reference model is a seven-layer classification of network communication. The concepts of application communication and session are separated, which would be clearly communicated based on the OSI reference model. Therefore, the correct answer is “OSI reference model.

×：TCP/IP model

The TCP/IP model is a layer design that is closer to the concept of a system than the OSI reference model; in the TCP/IP model, the application layer, presentation layer, and session layer of the OSI reference model are represented by a single application layer.

×：Data link model

There is no such model.

×：Biba model

Biba model is one of the security models that indicates that data cannot be changed without permission.

A captive portal is a mechanism that restricts communication with the outside world until user authentication, user registration, and user consent are performed when a terminal connects to the network.

〇：LAND attack

A LAND attack is an attack that penetrates firewalls that block bad requests; it is similar to the Fraggle attack, but it sends a request to the firewall with the sender as the target of the attack. This is a blind spot because the firewall, which is supposed to protect the inside of the system, is used for the attack.

×：Teardrop

Teardrop is an attack that halts the system by forging the offset of IP packets before they are split.

×：Christmas Tree Attack

A Christmas tree attack is an attack in which a packet is sent with a number of flags (URG, ACK, PSH, RST, SYN, FIN) and the response is observed.

×：CHARGEN attack

CHARGEN (port 19) is a protocol that returns an appropriate string.