Free Cisco 350-501 Practice Exam with Questions & Answers

In NetFlow export statistics, the BGP next hop information is not included by default. To include the BGP next hop in the export statistics, specific keywords related to BGP next hop must be configured with the version 9 NetFlow entry. This configuration allows for the measurement of network traffic on a per-BGP next hop basis, which is essential for detailed traffic analysis and accounting1. References: Configuring NetFlow BGP Next Hop Support for Accounting and Analysis - Cisco Systems1.

The configuration ip verify unicast source reachable-via any under interface gigabitethernet0/1 on Router 1 ensures that incoming packets have a source IP address that matches an entry in the FIB (Forwarding Information Base), indicating it’s reachable via a real interface. This helps mitigate attacks by dropping traffic with unreachable source addresses. References := Cisco

The IPv4 address family configuration under neighbor configuration-mode must be removed. The exhibit shows the configuration of a BGP neighborship between an ASBR and a directly connected BGP speaker. The ASBR is running Cisco IOS XR. The neighbor is configured with the IPv4 address family, which is not supported on Cisco IOS XR. To establish the BGP neighborship, the IPv4 address family configuration must be removed.

https://www.cisco.com/c/en/us/td/docs/routers/xr12000/software/xr12k_r41/routing/configuration/guide/routing_cg41xr12k_chapter1.html

When implementing traffic shaping on a network, the goal is to control the rate of traffic being sent into the network to avoid congestion. This is done by buffering excess packets and then scheduling them to be sent out at a steady rate.

Option A is correct because traffic shaping requires a queue with sufficient memory to buffer excess packets. When the traffic rate exceeds the configured maximum rate (shaping rate), the excess packets are temporarily stored in the queue until they can be sent out, ensuring a smooth flow of traffic without overwhelming the network1.

Option B is also correct as traffic shaping involves configuring token values in bytes. Tokens are used to represent permission to send a certain amount of data. The token bucket is filled with tokens at a steady rate, and packets can only be sent if there are enough tokens in the bucket. The token values determine the size of the bucket and the rate at which it is refilled, which in turn controls the rate of traffic1.

Option C is incorrect because packet remarking for excess traffic is not a component of traffic shaping. Packet remarking is typically used in conjunction with policing, where packets that exceed the rate limit can be remarked to a lower priority for downstream handling1.

Option D is incorrect in the context of traffic shaping. While a scheduling function is used to handle the packets that are delayed due to buffering, the scheduling itself is not part of the shaping mechanism but rather a function of the queuing system that works alongside shaping1.

Option E is incorrect as it pertains to traffic policing, not shaping. In traffic policing, packets that exceed a certain threshold are discarded or remarked, whereas shaping delays excess packets by buffering them1.

In the context of VPLS (Virtual Private LAN Service) configuration, the engineer should perform additional configurations to enable the virtual switch instance. The correct answer is Option A, which likely involves configuring interface VLAN and associating it with xconnect vfi to establish end-to-end LAN connectivity between customer’s remote offices. This is essential for enabling VPLS, which allows geographically dispersed sites to be connected over a service provider’s network as if they were on the same local area network.

Router R1 establishes TCP connections that are authenticated with an MD5 password. In the context of BGP (Border Gateway Protocol), TCP is used for establishing connections, and MD5 passwords can be used for authentication to enhance security.

 In Cisco Service Provider Network Core Technologies, an EVPN instance can be likened to a VRF (Virtual Routing and Forwarding). A VRF allows multiple instances of a routing table to co-exist within the same router at the same time. Similarly, EVPN provides separation between routing instances which aligns with how VRF operates.

 The ttl-security hops  command sets the maximum number of hops that a BGP message can traverse. In this case, setting ttl-security hops 2 means that the router will accept BGP packets from a neighbor (2.2.2.2) only if the TTL is 253 or more. This is because the default TTL value is 255, and for each hop, the TTL is decremented by 1. Therefore, a packet from a directly connected neighbor would have a TTL of 254 when it reaches the PE router. If the packet has traversed one more router (making it two hops away), the TTL would be 253 upon arrival.