JN0-232 Sample Questions Answers

When a new packet arrives that does not match an existing session, the SRX performs full flow-based processing. After ingress zone determination, the firewall must know the destination zone to evaluate security policies.

The SRX determines theegress zone by performing a route lookupon the packet’s destination IP address.

The routing decision identifies the outgoing interface, and the zone associated with that interface becomes theegress zone.

Session lookup (Option A) happens first but is only useful for existing sessions.

Destination port (Option B) is used for application identification, not zone determination.

Ingress zone properties (Option D) cannot determine the egress zone.

Adding interfaces (Option A):An interface must be assigned to a security zone before it can pass traffic. By default, interfaces are in the null zone and cannot send or receive traffic.

Exception traffic (Option B):Security zones define host-inbound-traffic settings, which determine what types of management or control-plane traffic (SSH, ICMP, SNMP) are permitted.

Routing instances (Options C and D):Security zones arespecific to a routing instanceand cannot include interfaces from multiple instances. Therefore, interfaces in the same zone cannot belong to different routing instances.

Correct Statements:A and B

License Requirement (Option B):NextGen Web Filtering (NGWF) is a licensed feature on SRX devices. Without a license, the service cannot operate.

Local vs. Cloud Lists (Option C):NGWF checkslocal block/allow lists first. If the URL does not match locally, the request is then checked against the Juniper cloud database.

Option A:Incorrect, since the cloud is only consulted if the URL is not in the local list.

Option D:Incorrect, as NGWF requires a valid subscription/license.

Correct Statements:NGWF requires a license, and it checks local lists before cloud lookup.

Themanagement functional zoneon SRX devices is a special predefined zone with unique characteristics:

It isautomatically created(Option C) and cannot be deleted.

It is used specifically formanagement-related traffic(Option A), such as SSH, Telnet, web management (J-Web), SNMP, and other control-plane services.

It does not contain revenue (data) interfaces (Option B is incorrect). Interfaces must be explicitly configured into user-defined zones.

The management zone can be referenced in policies if inter-zone communication involving management traffic is needed (Option D is incorrect).

Correct Statements:A and C

Default assignment:All logical interfaces are placed in thenull zone by defaultuntil explicitly assigned to a user-defined security zone (Option A is correct).

Removal from null zone:Once an interface is assigned to a security zone, it is removed from the null zone (Option D is correct).

No traffic acceptance:The null zone is a discard zone; it cannot be configured to accept any traffic (Option C is incorrect).

Policy behavior:Traffic rejected by a security policy is dropped according to the policy action. It is not forwarded to the null zone for logging (Option B is incorrect).

Correct Statements:A and D

In Juniper SRX flow-based packet processing, theflow moduleis responsible for security functions such as screening, session management, NAT, and policy enforcement. The processing order is critical:

Screens are applied before any session lookup.This ensures that packets are inspected for anomalies, floods, or protocol violations before consuming resources for session management. Examples of these screens include TCP SYN flood protection, ICMP flood protection, and port scanning protection.

After screening, thesession lookupoccurs. At this point, the firewall checks whether the packet belongs to an existing session in the session table. If a matching session is found, the packet bypasses policy evaluation and is forwarded according to the session state.

If no existing session is found, the packet continues throughroute lookup, NAT processing, and security policy evaluationbefore a new session is created.

Thus,screening occurs before the session lookup, protecting the system early in the flow process. This design ensures efficiency by dropping malicious or malformed traffic before allocating session resources.

From the exhibit, the content filter configuration is as follows:

Match Conditions:

Application:HTTP

Direction:download

File-types:exe

Action:

block

notification log

Analysis of Options:

Option A: Incorrect. The configuration specifies thedownload direction, not upload. Uploads of .exe files are unaffected.

Option B: Correct. Because the rule applies todownloads, .exe files will be blocked when users attempt to download them over HTTP.

Option C: Correct. The notification { log; } statement ensures that an entry will be added to the SRX device’s log when the action is triggered.

Option D: Incorrect. No configuration for sending e-mail notifications is shown in the rule. Only logging is specified.

Correct Statements:B and C

Option B:Correct. Interfaces in the same security zone must belong to the same routing instance; zones cannot span multiple routing instances.

Option D:Correct. A security zone can contain multiple interfaces, allowing grouping of similar trust levels (e.g., multiple LAN subnets in a trust zone).

Option A:Incorrect. An interface can belong to only one zone at a time.

Option C:Incorrect. Interfaces within the same zone cannot be split across routing instances.

Correct Statements:Interfaces in the same zone must share the same routing instance, and a zone can contain multiple interfaces.

Static NAT:Provides a one-to-one bidirectional mapping between internal and external IP addresses. When configured, the translation automatically applies in both directions (Option A is correct). It does not use Port Address Translation (Option C is incorrect).

Destination NAT:Allows external clients to access internal resources by translating the destination address. It supportsport forwardingso specific services (e.g., HTTP on port 80) can be forwarded to an internal host (Option D is correct). It does not require equal-sized address ranges (Option B is incorrect).

Correct Characteristics:Static NAT is bidirectional, and Destination NAT supports port forwarding.

SRX Series devices providecontent securityfeatures that rely on advanced identification mechanisms. File identification is not based merely on file extensions (which can be easily spoofed), but instead ondeep inspection techniques:

AppID (Application Identification):AppID is part of the AppSecure suite, allowing the device to classify applications and content regardless of port or protocol. This enables the SRX to detect applications and their related content for enforcement.

Protocol-based file type identification:The SRX can recognize and identify file types embedded withinHTTP, FTP, and e-mail (SMTP, IMAP, POP3) protocols. This providesaccurate content inspection and filtering, independent of file naming conventions.

Why not the others?

File extensions (Option A) are not reliable for content security, so SRX does not use them.

ALGs (Option D) are used for protocol handling, such as SIP or FTP control channels, not for content identification.

Security Director (Option B):A Junos Space application that provides a centralized interface for managing, monitoring, and maintaining multiple SRX firewalls.

Juniper Secure Analytics (Option A):Focuses on SIEM/log analysis, not centralized firewall management.

Identity Management Service (Option C):Provides user identity integration for policy enforcement, not a management UI.

Secure Connect (Option D):A VPN client solution, not a firewall management platform.

Correct UI:Security Director

Multiplerouting instances(such as virtual routers or VRFs) can be configured on an SRX to provide separation of routing tables. This enables:

Maintaining separation of routing information (Option B):Different departments, tenants, or customers can have their own independent routing domains for security and isolation.

SNMP monitoring (Option A) is unrelated to routing instances.

Routing protocols (Option C) can be run inside each instance, but the purpose of multiple instances is separation, not general routing protocol management.

Simplifying interface configuration (Option D) is not a function of routing instances.

Correct Purpose:To maintain separation of routing information for security purposes.

Afeature profilein a UTM (Unified Threat Management) configuration defines how a specific UTM feature should operate. Examples include:

Anantivirus feature profilethat specifies the type of scanning to perform (streaming or full file-based).

Aweb filtering feature profilethat defines filtering methods, categories, and actions.

Anantispam profilethat defines how spam detection and actions are performed.

Feature profiles do not directly apply to traffic or policies. Instead, they arereferenced inside a UTM policy, and then that policy is applied to a security policy.

Therefore, a feature profile’s purpose is todefine the operation of a specific UTM feature.

When two networks use the same private IP address ranges, conflicts occur. The solution is to use address translation techniques on the SRX:

NAT (Network Address Translation):Translates private IP addresses to another IP range, enabling connectivity between overlapping private networks.

PAT (Port Address Translation):Extends NAT by allowing multiple private IPs to share one or a few public IPs using different port numbers. This is especially useful when there is a limited pool of public IP addresses.

Other options:

IDP (Option A):Intrusion Detection and Prevention, unrelated to address overlap.

BGP (Option C):A routing protocol, but it does not solve overlapping IP addressing problems.

Correct Features:NAT and PAT

Global policies (Option D):Evaluated before zone-based policies. They allow centralized control and can apply across all zones. Perfect for Internet-to-private traffic that must be enforced before other rules.

Routing policy (Option A):Controls routing decisions, not traffic forwarding/security.

Default policy (Option B):Denies all traffic by default, but cannot be customized for early evaluation.

Zone policy (Option C):Zone-based policies apply after global policies and are limited to specific zone pairs.

Correct Policy Type:Global policy

Intra-zone traffic:On SRX devices, traffic between interfaces in the same security zone is allowedwithout requiring a security policy(Option C is correct). Policies are only evaluated for inter-zone traffic.

Junos-host functional zone:This zone is a predefined functional zone that allows administrators to apply policies controlling access to the SRX firewall itself, such as SSH, HTTP, or SNMP traffic (Option D is correct).

Null zone:This zone is a predefined discard zone. Interfaces placed in the null zone drop all traffic. It does not allow policy logging of dropped control plane traffic (Option A is incorrect).

Management functional zone:This is used to define management interfaces, not the “functional zone” as stated in Option B (incorrect wording).

Correct Statements:C and D