Juniper JN0-231 Exam

This is necessary to ensure that the application firewall can properly identify the application and the correct security policies can be applied before allowing any traffic to pass through.

If the first packet was allowed to pass without first being identified, then the application firewall would not know which security policies to apply - and this could potentially lead to security vulnerabilities or breaches. So it's important that the first packet is held until the application is identified.

Juniper ATP should be configured with C&C feeds that contain lists of malicious domains and IP addresses in order to prevent IP cameras from becoming zombies in a DDoS attack.

This is an important step to ensure that the IP cameras are protected from malicious requests - and thus, they will not be able to be used in any DDoS attacks against the facility.

Junos-host and null are two non-configurable zones that exist by default on an SRX Series device. Junos-host is the default zone for all internal interfaces and services, such as management and other loopback interfaces. The null zone is used to accept all traffic that is not explicitly accepted by other security policies, and is the default zone for all unclassified traffic. Both zones cannot be modified or deleted.

By default, TCP has a 30-minute idle timeout, and UDP has a 60-second idle timeout. Additionally, known IP protocols have a 30-minute timeout, whereas unknown ones have a 60-second timeout. Setting the inactivity timeout is very useful, particularly if you are concerned about applications either timing out or remaining idle for too long and filling up the session table. According to the Juniper SRX Series Services Guide, this can be configured using the 'timeout inactive' statement for the security policy.

The default value of the dead peer detection (DPD) interval for an IPsec VPN tunnel is 5 seconds. DPD is a mechanism that enables the IPsec device to detect if the peer is still reachable or if the IPsec VPN tunnel is still active. The DPD interval determines how often the IPsec device sends DPD packets to the peer to check the status of the VPN tunnel. A value of 5 seconds is a common default, but the specific value can vary depending on the IPsec device and its configuration.

Juniper Networks Technical Documentation: Configuring IPsec VPNs: https://www.juniper.net/documentation/en_US/junos/topics/task/configuration/ipsec-vpn-overview-srx-series.html