Juniper Security, Specialist (JNCIS-SEC) JN0-335 Exam Dumps: Updated Questions & Answers (November 2025)

AppQoS is a service that allows you to prioritize and manage the quality of service (QoS) for different types of applications on SRX Series devices. AppQoS uses application signatures to identify and classify the traffic, and then applies QoS policies to assign bandwidth, priority, and scheduling parameters to the traffic. AppQoS can help you optimize the performance of critical applications, such as VoIP, and ensure that they get the required bandwidth and latency in a congested network12. In this scenario, you can use AppQoS to prioritize the VoIP traffic over other traffic and guarantee its QoS on the SRX Series device at the branch office. References:

Understanding Application Quality of Service

Configuring Application Quality of Service

The infected host cloud feed is a list of IP addresses that have been identified as compromised or infected by malware. The feed is updated by Juniper ATP Cloud based on the detection of malicious activity from the hosts, such as contacting known command-and-control servers. When a host on the network reaches the configured threat level threshold, its IP address is automatically added to the infected host cloud feed and blocked from communicating with any other hosts on the Internet. The other feeds are not relevant for this situation. The command-and-control cloud feed is a list of IP addresses that are known to be used by malware for remote control and communication. The allowlist and blocklist feed is a user-defined list of IP addresses that are either allowed or denied by the SRX Series device. The custom cloud feed is a user-defined list of IP addresses that are associated with a specific category or threat level. References:

Infected Hosts: More Information

Juniper’s Attacker IP feed bolsters threat protection with SecIntel

ATP Appliance and SRX Series Threat Level Comparison Chart

The SRX Series device will drop packets from the infected hosts with a threat level of 8 and no log message will be generated. This is because the security intelligence profile “ATP_Infected-Hosts” has a rule “Rule-1” that matches packets with a threat level of 8 and the action is to block and drop them. There is no log option specified in the action, so no log message will be generated. Options A and B are not correct because the rule only matches packets with a threat level of 8, not 8 or above. Option C is not correct because the action is to drop, not permit, the packets. References: The answer can be verified from Juniper’s official documentation on security intelligence available on their website. Here are some relevant links:

Security Intelligence Feature Guide for Security Devices

security-intelligence | Junos OS

Configure the Security Intelligence Policy on the SRX Series Device

Referring to the SRX Series flow module diagram shown in the exhibit, application security is processed at the Services ALGs stage. Application Layer Gateways (ALGs) are software components that enable the SRX Series device to provide application-level security for specific protocols and applications1.

ALGs inspect the application layer payload of packets and perform various actions, such as modifying the payload, opening pinholes, creating sessions, applying security policies, and enforcing application-specific behavior12.

ALGs are required for protocols and applications that embed IP address information or port numbers in the application layer data, that open secondary connections, or that are dynamically assigned ports1. Some examples of protocols and applications that require ALGs are FTP, SIP, H.323, RTSP, PPTP, and DNS2.

ALGs are configured as part of the security policy and are applied to the traffic that matches the policy criteria. ALGs can also be enabled or disabled globally or per zone12.

References:

1: Application Layer Gateways Overview

2: Application Layer Gateways Feature Guide for Security Devices

After JSA receives external events and flows, the data goes through the following steps in the event and flow pipeline 1:

Event and flow collection: JSA accepts event logs and flow records from various sources by using different protocols and methods. The data is parsed and normalized into a JSA-usable format.

Event and flow processing: JSA applies rules, custom properties, and anomaly detection to the data. The data is also coalesced, filtered, and forwarded as needed. The data is stored in an asset database and an Ariel database for further analysis and reporting.

Event and flow correlation: JSA analyzes the data for patterns that indicate malicious activity or policy violations. JSA generates offenses, alerts, and notifications based on the correlation rules and building blocks.

Event and flow response: JSA responds to the offenses and alerts by taking active measures such as blocking IP addresses, quarantining hosts, or updating reference data. JSA also provides investigation and remediation tools for analysts to handle the incidents. References:

1: JSA Events and Flows | Junos OS | Juniper Networks

The session table is a limited resource for SRX Series devices. If the session table is full, any new sessions will be rejected by the device. The aggressive session-aging mechanism accelerates the session timeout process when the number of sessions in the session table exceeds the specified high-watermark threshold. This mechanism minimizes the likelihood that the SRX Series devices will reject new sessions when the session table becomes full1. To perform aggressive session aging, you need to configure the following parameters1:

early-ageout –During aggressive session aging, the sessions with an age-out time lower than the early-ageout threshold are marked as invalid. The early-ageout configuration specifies the timeout value, in seconds, that will be applied once the high-watermark value is met. For example, if you set the early-ageout to 30 seconds, any session that has been inactive for at least 30 seconds will be aged out when the high-watermark is reached2.

high-watermark –The device performs aggressive session aging when the number of sessions in the session table exceeds the high-watermark threshold. The high-watermark configuration specifies the percentage of how much of the session table can be allocated before applying a more aggressive age-out timer. For example, if you set the high-watermark to 90 percent, the device will start aging out sessions more aggressively when the session table reaches 90 percent of its capacity3.

Therefore, the correct statements are B and D.

References: Understanding Aggressive Session Aging high-watermark early-ageout

References: Unified Security Policies, Understanding Security Policy Elements, Anyone with good understanding of Unified Security Policies (SRX)

The vSRX is a virtual firewall that offers the same features as the physical SRX Series firewalls, but in a virtualized form factor. It supports next-generation firewall (NGFW) capabilities, networking, and automated lifecycle management. It also integrates with cloud orchestration tools and software-defined networking (SDN) solutions1

The vSRX supports VMXNET3 vNICs, which are optimized for performance in virtualized environments. VMXNET3 vNICs offer enhanced networking features such as jumbo frames, hardware offloads, and multicast filtering2

The vSRX runs on Linux as the base OS, which provides a stable and secure platform for the Junos OS and the firewall functionality. Linux also enables the vSRX to leverage the native hypervisor drivers and APIs for better performance and compatibility3

References: 1: vSRX Virtual Firewall | Juniper Networks US 2: vSRX Virtual Firewall for VMware - TechLibrary - Juniper Networks 3: vSRX Overview - TechLibrary - Juniper Networks

 Juniper ATP Cloud is a cloud-based service that provides advanced malware detection and prevention for the network. It uses machine learning to find and block both known and unknown cyberthreats, analyzing files and network traffic looking for signs of malicious behavior. One of the methods that Juniper ATP Cloud uses to identify zero-day threats is dynamic analysis, which is the process of executing suspicious files or code in a sandbox environment and observing their behavior and network activity. Dynamic analysis can uncover zero-day malware threats and malicious connections, including botnets and command-and-control servers hiding in encrypted traffic, by detecting anomalous or malicious patterns. Dynamic analysis is complemented by other methods, such as static analysis, which examines the file structure and content without executing it, and machine learning, which uses artificial intelligence to classify and predict threats based on previous data and models. References:

[Juniper Advanced Threat Prevention Products] 1

[Juniper Advanced Threat Prevention Datasheet] 2

[Juniper Advanced Threat Prevention | NetworkScreen.com] 3

[Introduction to Juniper ATP Cloud | ATP Cloud | Juniper Networks] 4

[JUNIPER ADVANCED THREAT PREVENTION CLOUD SERVICES DESCRIPTION] 5

Adaptive Threat Profiling is a feature that allows SRX Series Firewalls to generate, propagate, and consume threat feeds based on their own advanced detection and policy-match events. This feature enables you to configure security or IDP policies that, when matched, inject the source IP address, destination IP address, source identity, or destination identity into a threat feed, which can be leveraged by other devices as a dynamic-address-group (DAG). With adaptive threat profiling, the Juniper ATP Cloud service acts as a feed-aggregator and consolidates feeds from SRX across your enterprise and shares the deduplicated results back to all SRX Series Firewalls in the realm at regular intervals. SRX Series Firewalls can then use these feeds to perform further actions against the traffic. This feature allows you to find systems running applications that increase the risks on your network and ensure these systems are processed through IPS and Juniper ATP Cloud for malware and virus protection1. References:

Adaptive Threat Profiling Overview and Configuration

Adaptive Threat Profiling Overview

Juniper Launches Adaptive Threat Profiling, New VPN Features

Juniper Networks Answers Who and What is On the Network with Risk-Based Access Control Capabilities and New VPN Application

Adaptive Threat Profiling Overview | SD Cloud