312-38 Exam Dumps : Certified Network Defender (CND)

 A TCP null scan attempt is a technique used in network scanning where the TCP packet sent has no flags set. This type of scan can sometimes penetrate through routers and firewalls that filter incoming packets based on certain flags because the absence of flags can prevent the packet from being filtered out. The TCP null scan is particularly useful for identifying open ports on a target system. If a port is open, the target system will not respond to the null scan, but if the port is closed, the system will send a TCP RST packet in response. This scanning method is not supported by Windows because Windows systems typically respond with a RST packet regardless of whether the port is open or closed, making it ineffective for distinguishing between the two states on those systems.

References: The TCP null scan’s ability to bypass certain types of filters and its behavior in response to open and closed ports are documented in various network security resources, including the Nmap documentation and other network security analysis articles12. These sources confirm the effectiveness of TCP null scans in penetrating through filters set up by routers and firewalls and their unsupported status on Windows systems.

Michael would view the firewall log to track employee actions on the organization’s network. Firewall logs are records of events that are captured by the firewall. They typically include details about allowed and denied traffic, network connections, and other transactions through the firewall. By analyzing these logs, network administrators can monitor network usage, detect unusual patterns of activity, and identify potential security threats or breaches.

References: The importance of monitoring firewall logs is emphasized in the EC-Council’s Certified Network Defender (C|ND) program. It is part of the network traffic monitoring and analysis, which is crucial for detecting and responding to incidents on the network123.

In a pull-based mechanism, the client initiates the request to the server to fetch data or services. This model contrasts with the push-based mechanism, where the server initiates the data transfer to the client without a specific request.

In the context of network security and data transfer:

• Pull-based mechanisms allow clients to request updates or data as needed, giving them control over the timing and frequency of the requests.
• This model is commonly used in content delivery networks (CDNs), software updates, and various client-server applications where clients need to periodically check for new information or updates.

References:

• EC-Council Certified Network Defender (CND) Study Guide
• Client-Server Model Documentation and Examples