Pass the Juniper JNCIS-SEC JN0-336 Questions and answers with Dumpstech

The correct answer is B. ESP. In IPsec, the security protocol responsible for encrypting protected traffic is Encapsulating Security Payload (ESP). Juniper defines ESP as the IPsec protocol used for encrypting the IP packet and authenticating its contents. In practical SRX VPN design, ESP is the normal protocol selected when confidentiality is required because it can provide encryption, packet integrity, authentication, and anti-replay protection depending on the configured IPsec proposal.

Option A, SHA-1, is incorrect because SHA-1 is an authentication/hash algorithm, not an IPsec security protocol and not a payload encryption mechanism. Option C, AH, is incorrect because Authentication Header validates packet source and integrity but does not encrypt payload data. AH is therefore unsuitable when the requirement explicitly says payload data must be encrypted. Option D, PFS, is incorrect because Perfect Forward Secrecy is a key-exchange property used during Phase 2 rekeying; it strengthens key independence but does not itself encrypt packets. In Junos IPsec configuration logic, the security protocol decision is between ESP and AH, and encryption requires ESP. Reference topics: IPsec VPN, ESP, AH, IPsec security protocols, payload confidentiality, IPsec proposal design.

The correct answers are B and C. In Junos route-based IPsec VPNs, the default proxy ID is broad: local 0.0.0.0/0, remote 0.0.0.0/0, and service any. This default behavior allows routed traffic entering the secure tunnel interface to determine what is protected by the VPN rather than requiring a narrow policy-based encryption domain. Juniper’s IPsec VPN configuration guidance also states that proxy IDs are used in Phase 2 negotiations, and that a proxy ID mismatch is one of the common causes of Phase 2 failure. For interoperability with some third-party VPN peers, Juniper notes that proxy IDs may need to be manually configured to match the peer.

Option A is wrong because proxy IDs can override default route-based behavior when manually configured, especially when a peer requires specific local and remote protected subnets. Option D is wrong because proxy IDs are not created during IKE Phase 1. Phase 1 builds the secure IKE channel; proxy IDs belong to Phase 2/IPsec SA negotiation, where the peers agree on traffic selectors for encrypted traffic. Reference topics: IPsec VPN, route-based VPNs, proxy IDs, Phase 2 negotiation, traffic selectors, third-party VPN interoperability.

The correct answers are C and D. The exhibit shows ESP encrypted bytes = 0, ESP decrypted bytes = 0, encrypted packets = 0, and decrypted packets = 0. That means no traffic is successfully passing through the IPsec tunnel. Juniper’s show security ipsec statistics command displays ESP encrypted/decrypted packet and byte counters, so zero values on these counters indicate that the tunnel is not successfully carrying protected ESP traffic.

Option C is also correct because the output shows ESP authentication failures and ESP decryption failures. Since ESP is the IPsec protocol responsible for encrypted payload handling, failures in ESP authentication/decryption point to an ESP/IPsec Phase 2 mismatch or incorrect configuration, such as mismatched authentication algorithm, encryption algorithm, keys, proposal parameters, or incompatible negotiated SA settings. Juniper’s IPsec overview explains that Phase 2 negotiates the IPsec SA used to authenticate traffic flowing through the tunnel, so ESP-related failures belong to the IPsec/ESP configuration path rather than AH.

Option A is wrong because the AH counters and AH authentication failures are zero; the evidence is not pointing to AH. Option B is unsupported because the output does not show peer reboot behavior. Reference topics: IPsec VPN, ESP statistics, Phase 2/IPsec SA negotiation, ESP authentication failures, ESP decryption failures.

The correct answer is B. ip-notify. When administrators want visibility without enforcement impact, ip-notify is the correct IP action. Juniper Security Director documentation defines IP Notify as an IP action that does not take any action against future traffic but logs the event. That is exactly the requirement in the question: traffic matching the IDP condition must not be blocked, closed, or rate-limited until administrators have reviewed the events and decided whether enforcement is appropriate.

Option A, ip-block, is wrong because it blocks future packets matching the IP action rule. That would immediately impact traffic. Option C, ip-connection-rate-limit, is wrong because it limits the connection rate and therefore changes traffic behavior before administrators complete evaluation. Option D, ip-close, is also wrong because it closes matching future sessions by sending reset packets to the client and server, which is disruptive. In a safe evaluation or tuning phase, the proper approach is to log and observe first, then move to stronger actions such as block, close, or rate-limit only after the detected condition has been validated. Reference topics: IDP IP actions, ip-notify, event logging, non-disruptive evaluation mode, IDP policy tuning.

The correct answers are A and D. Preparing Active Directory for JIMS requires creating limited-permission service accounts and assigning those accounts to the required Active Directory groups. Juniper’s JIMS deployment guidance states that you must create service accounts so JIMS can read from the defined directory services and identity producers; if PC probing is used, a service account is also required for that function. The same JIMS documentation includes a section named Configure Limited-Permission User Accounts, followed by Add Limited Permission User Accounts to Active Directory Groups.

Option A is correct because the JIMS preparation workflow commonly uses limited-permission accounts for event log access and PC probe access. Juniper identifies accounts such as JIMS-EventLogRemoteAccess and JIMS-PC-Probe in the Active Directory group-membership procedure. Option D is correct because those limited accounts must be added to the proper AD groups, including Event Log Readers and the groups required for remote management or PC probe operation.

Option B is wrong because the tested preparation requirement is not three limited-access accounts. Option C is wrong because JIMS should not be prepared by adding a broad full-access account; the course objective is least-privilege identity collection. Reference topics: JIMS, Active Directory preparation, limited-permission service accounts, Event Log Readers, PC probe account.

The correct answers are B, D, and E. Security Director device onboarding depends on management reachability and valid administrative access. Juniper’s device discovery documentation states that Junos Space discovers network devices using SSH, with optional ping and SNMP, and connects to the physical device to retrieve running configuration and status information. It also explains that device authentication uses administrator login credentials, SSH credentials, SNMP settings, or keys depending on the discovery method.

Option E is required because Security Director must target a reachable management IP address or hostname. Juniper’s discovery-profile workflow explicitly uses the target IP address, hostname, IP range, or subnet to locate devices. Option D is required because invalid username/password or insufficient privileges prevent discovery and management; Juniper’s device-management guidance identifies credentials as required input for discovering devices. Option B is required because onboarding uses SSH, so the correct SSH service and port must be reachable. Juniper’s device access procedure explicitly includes a Port field for the SSH connection.

Option A is wrong because chassis serial number is not the normal troubleshooting field for Security Director discovery. Option C is wrong because active security policies do not determine whether Security Director can initially discover and onboard the device. Reference topics: Security Director, device discovery, SSH access, management IP reachability, authentication credentials.

The correct answer is D. exempt. In Junos IDP, the exempt rulebase is specifically used to prevent selected traffic from triggering known false-positive detections. Juniper’s IDP documentation explains that exempt rules can be configured when an IDP policy generates false positives for a particular attack object, source, destination, or traffic pattern. The exempt rulebase lets the administrator exclude matching traffic from attack detection while still allowing the rest of the IDP policy to inspect other traffic normally.

Option A, IPS, is wrong because the IPS rulebase is the main inspection rulebase used to detect and act on attacks. It is where attack objects and actions are commonly applied, but it is not the rulebase designed to eliminate false positives. Option B, monitor, is not the correct false-positive elimination mechanism. Monitoring can help observe behavior, but it does not exempt traffic from matching an attack object. Option C, signature, is wrong because signatures are attack-detection patterns, not a rulebase type used to suppress false positives. The operational correction for noisy or irrelevant matches is to create an exempt rule for the specific trusted source, destination, or attack object. Reference topics: IDP rulebases, exempt rulebase, false-positive tuning, attack objects, IPS inspection.

The correct answers are A and D. Juniper documentation describes domain PC probing as a supplement to event-log reading. When a user logs in to the domain, the domain controller event log normally provides the user-to-IP mapping. If that IP address-to-username mapping is not available from the event log, JIMS initiates a domain PC probe to the endpoint to obtain the active username and domain. JIMS can also use probes to determine a device’s status after the logged-in state expires, so the operational idea is not blind periodic probing; it is used to resolve or validate identity state when normal event-log information is missing or stale.

Option D is correct because the result of identity collection is reported back to SRX Series devices. JIMS generates reports containing IP address, username, and group relationship information, keeps a list of reports communicated to SRX devices, and sends those reports so SRX devices can create authentication-table entries for identity-aware policy enforcement. Options B and C are wrong because the tested PC-probe behavior is not “every 30 seconds” or “every 60 seconds.” Those values confuse PC probing with other timers or query intervals. Reference topics: JIMS, domain PC probing, event-log identity mapping, SRX authentication table, identity-aware security policies.

The correct answer is D. maintaining a centralized authentication table. Juniper Identity Management Service, or JIMS, is used with SRX Series Firewalls to collect user-identity information from identity sources such as Microsoft Active Directory, domain controllers, and Exchange servers, then provide that identity data to SRX enforcement points. Juniper describes JIMS as storing IP address, username, and group-relationship information in its cache and generating authentication entries used for user-based or group-based access control on SRX firewalls. Juniper’s Identity-Aware Firewall documentation also states that the authentication table contains the IP address, username, and group mapping information used as the authentication source.

Option A is wrong because JIMS is not an email-encryption service. Option B is wrong because malicious-code logging belongs to security inspection features such as antivirus, IDP, or ATP workflows, not JIMS. Option C is wrong because network data encryption is handled by technologies such as IPsec VPN or SSL/TLS, not identity management. JIMS exists to centralize identity-to-IP mapping so identity-aware security policies can match users and groups instead of relying only on source IP addresses. Reference topics: Identity-Aware Security Policies, JIMS, authentication table, user-to-IP mapping, group-based policy enforcement.