Cisco 350-501 Online Practice Questions and Exam Preparation

Cisco 350-501 Online Questions & Answers

• Question 41:

  Refer to the exhibit.

  

  All edge routers are fully meshed via the IBGP and IS-IS routing protocols, and LDP is used for label distribution. The network engineer must protect the TE tunnels and MPLS network from interface flaps and retain label information in the LIB cache for 10 minutes.

  Which action completes the implementation?

  A. Enable the MPLS TTL signaling expiration timer with the timeout set to 10 minutes.
  B. Implement MPLS label protection with a duration of 10 minutes.
  C. Enable signaling synchronization for MPLS traffic engineering with the timeout set to 600 seconds.
  D. Implement LDP session protection with a duration of 600 seconds.
  B. Implement MPLS label protection with a duration of 10 minutes.

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  Explanation

• Question 42:

  Refer to the exhibit

  

  R1 is connected to two service providers and is under a DDoS attack.

  Which statement about this design is true if URPF in strict mode is configured on both interfaces?

  A. R1 drops all traffic that ingresses either interface that has a FIB entry that exits a different interface.
  B. R1 drops destination addresses that are routed to a null interface on the router.
  C. R1 permits asymmetric routing as long as the AS-PATH attribute entry matches the connected AS.
  D. R1 accepts source addresses on interface gigabitethernet0/1 that are private addresses.
  A. R1 drops all traffic that ingresses either interface that has a FIB entry that exits a different interface.

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  Explanation

  Unicast Reverse Path Forwarding (uRPF) in strict mode ensures that packets are received on the interface that the router would use to forward the return traffic. If a packet is received on an interface that is not the best reverse path, the packet is dropped. This helps mitigate IP address spoofing and DDoS attacks.

• Question 43:

  How does Cisco MPLS TE use OSPF extensions to allow for optimized transit between a headend router and a destination router?

  A. Router LSAs share router link advertisements to each router within the MPLS environment so that tunnels can be built bidirectionally.
  B. ASBR Summary LSAs share OSPF domain information so that the two routers know how to reach each other during tunnel setup.
  C. Network LSAs share RSVP information to build the tunnel between the two routers.
  D. Opaque LSAs calculate and establish unidirectional tunnels that are set according to the network constraint.
  D. Opaque LSAs calculate and establish unidirectional tunnels that are set according to the network constraint.

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  Explanation

  Cisco MPLS TE uses OSPF extensions to allow for optimized transit between a headend router and a destination router by utilizing Opaque LSAs. Opaque LSAs allow for the calculation and establishment of unidirectional tunnels that are set according to the network constraint. The tunnels are built bidirectionally by utilizing Router LSAs, which share router link advertisements to each router within the MPLS environment. ASBR Summary LSAs are also used to share OSPF domain information so that the two routers know how to reach each other during tunnel setup. Furthermore, Network LSAs are used to share RSVP information which is necessary for setting up the tunnel between the two routers.

• Question 44:

  Refer to the exhibit.

  

  In the service provider network, routers PE1, PE2, and PE4 have access to the internet and provide access to customer networks. Router PE3 is used for access to other customer systems. In accordance with a new SLA, an engineer is updating settings on this network so that router CE1 accesses the internet via PE1 instead of PE2. Which two tasks must the engineer perform to complete the process? (Choose two.)

  A. On PE1, configure the internet VRF with import route target 102:102.
  B. On PE1 and PE4, configure the internet VRF with import route targets 102:102 and 104:104.
  C. On PE2, configure the internet VRF with import route target 102:102.
  D. On PE2 and PE3, configure the internet VRF with import route target 101:101.
  E. On PE2, configure the CE1 VRF with import route target 101:101.
  A. On PE1, configure the internet VRF with import route target 102:102.
  E. On PE2, configure the CE1 VRF with import route target 101:101.

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  Explanation

• Question 45:

  What causes multicast traffic to permanently stay on the shared tree and not switch to the source tree?

  A. The SPT threshold is set to infinity.
  B. The RP IP address is configured incorrectly.
  C. The RP announcements are being filtered.
  D. SSM range is being used.
  A. The SPT threshold is set to infinity.

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  Explanation

  The SPT threshold set to infinity causes multicast traffic to permanently stay on the shared tree and not switch to the source tree. In multicast routing, the Shortest Path Tree (SPT) threshold determines when a router should switch from receiving multicast traffic on the shared tree to receiving it on a source tree. Setting the SPT threshold to infinity means that the router will always receive multicast traffic on the shared tree.

  https://www.cisco.com/c/en/us/td/docs/ios/solutions_docs/ip_multicast/White_papers/mcst_ ovr.html

• Question 46:

  Refer the exhibit.

  

  Users on a network connected to router R3 report slow speeds when they connect to the server connected to R2. After analyzing traffic on the network, a network engineer identified congestion on the link between R2 and R3 as the cause.

  Which QoS service must the engineer implement to drop traffic on the link when it exceeds a configured threshold?

  A. first-in, first-out
  B. traffic shaping
  C. class-based weighted fair queueing
  D. traffic policing
  D. traffic policing

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  Explanation

  https://www.cisco.com/c/en/us/support/docs/quality-of-service-qos/qos-policing/19645-policevsshape.html

• Question 47:

  Refer to the exhibit.

  

  Tier 1 ISP A purchased several Tier 2 ISPs to increase their customer base and provide more regional coverage. ISP A plans to implement MPLS services in the access layer, with scalability up to 100,000 devices in one packet network and service recovery up to 50 ms. The network architect decided to use different independent IGP and LDP domains and interconnect LSPs that are based on RFC 3107.

  Which two actions must the network engineer perform to meet the requirements? (Choose two.)

  A. Implement BGP inline RR functionality with next-hop-self capabilities on routers R2 and R3.
  B. Implement the IS-IS routing protocol on the access domain.
  C. Implement BGP connectivity between routers R1 and R4 with VPNv4 address family enabled.
  D. Configure three OSPF areas, with Area 0 in the core domain, and Areas 2 and 3 in the aggregation domain.
  E. Implement BGP PIC core functionality on routers R2 and R3.
  A. Implement BGP inline RR functionality with next-hop-self capabilities on routers R2 and R3.
  E. Implement BGP PIC core functionality on routers R2 and R3.

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  Explanation

• Question 48:

  Refer to the exhibit.

  

  What type of configuration is it?

  A. It is configuration that requires OSPF to also be running to have optimized Cisco MPLS TE tunnels
  B. It is configuration that requires a dynamic Cisco MPLS TE path to be configured for the tunnel to run
  C. It is configuration for the head-end router of a Cisco MPLS TE tunnel with segment routing
  D. It is configuration that requires an explicit Cisco MPLS TE path to be configured for the tunnel to run
  C. It is configuration for the head-end router of a Cisco MPLS TE tunnel with segment routing

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  Explanation

  The configuration shown is for the head-end router of a Cisco MPLS TE tunnel with segment routing. This setup involves commands related to segment routing and MPLS traffic engineering tunnels, such as "mpls traffic-eng tunnels", "segment-routing mpls", and "segment-routing prefix-sid-map advertise-local". These commands configure the head-end router to effectively create and manage TE tunnels using segment routing. References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) - Cisco SPCOR Training and Certification.

• Question 49:

  A network engineer is testing an automation platform that interacts with Cisco networking devices via NETCONF over SSH. In accordance with internal security requirements:

  1. NETCONF sessions are permitted only from trusted sources in the 172.16.20.0/24 subnet.

  2. CLI SSH access is permitted from any source.

  Which configuration must the engineer apply on R1?

  A. configure terminalhostname R1ip domain-name mydomain.comcrypto key generate rsaip ssh version 1access-list 1 permit 172.16.20.0 0.0.0.255netconf ssh acl 1line vty 0 4transport input sshend
  B. configure terminalhostname R1ip domain-name mydomain.comcrypto key generate rsaip ssh version 2access-list 1 permit 172.16.20.0 0.0.0.255access-list 1 permit anynetconf sshline vty 0 4access-class 1 intransport input sshend
  C. configure terminalhostname R1ip domain-name mydomain.comcrypto key generate rsaip ssh version 1access-list 1 permit 172.16.20.0 0.0.0.255access-list 2 permit anynetconf sshline vty 0 4access-class 2 intransport input sshend
  D. configure terminalhostname R1ip domain-name mydomain.comcrypto key generate rsaip ssh version 2access-list 1 permit 172.16.20.0 0.0.0.255netconf ssh acl 1line vty 0 4transport input sshend
  D. configure terminalhostname R1ip domain-name mydomain.comcrypto key generate rsaip ssh version 2access-list 1 permit 172.16.20.0 0.0.0.255netconf ssh acl 1line vty 0 4transport input sshend

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  Explanation

• Question 50:

  A company uses PIM-SM multicast with IGMPv2 to stream training videos from a server in one network to hosts in a different network. As the company has grown, the networking team decided to implement SSM to improve efficiency for multicast within Layer 2.

  Which action must the team take to begin the process?

  A. Configure an IGMP querier and implement Cisco Express Forwarding across the network.
  B. Implement PIM-DM to enable the routers on the LAN to identify SSM-capable multicast hosts.
  C. Implement IGMPv3 and deprecate IGMPv2.
  D. Implement IGMPv3 simultaneously with IGMPv2 on the individual links that must support SSM and PIM-DM.
  C. Implement IGMPv3 and deprecate IGMPv2.

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  Explanation