Cisco 642-885 Online Practice Questions and Exam Preparation

Cisco 642-885 Online Questions & Answers

• Question 71:

  Which field in the IPv6 header can be used to set the DSCP value?

  A. Flow Label
  B. Type of Service
  C. Traffic Class
  D. Precedence
  E. EXP
  C. Traffic Class

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  Traffic Class The Traffic Class field is an 8 bit field that is used to signify the importance of the data contained within this specific packet. With IPv4, this information was signified with the TOS field and supported both IP precedence and Differentiated Services Code Point (DSCP). The Traffic Class field used with IPv6 supports DSCP solely; this specification uses the first 6 bits to indicate the Per Hop Behavior (PHB) of the contained data; these PHB's are defined in RFC 2474 and its additions.

• Question 72:

  Refer to the exhibit.

  

  R5 is configured as the RP for the PIM-SM domain for AS 1020. If R3 and R4 are correctly configured, which Cisco IOS-XE configuration should be done on R5 to configure it as a PIMv3 BSR router?

  A. ip pim send-rp-announce loopback 0 scope 16 int gi1/3 , gi 1/4 ip pim sparse-mode int gi 1/1 ip pim bsr-border
  B. ip pim rp-candidate loopback 0 int gi1/3 , gi 1/4 ip pim sparse-mode int gi 1/1 ip pim bsr-border
  C. ip pim rp-candidate loopback 0 int gi1/3 , gi 1/4 ip pim sparse-mode ip pim bsr-border
  D. ip pim send-rp-announce loopback 0 scope 16 int gi1/3 , gi 1/4 ip pim sparse-mode ip pim bsr-border
  B. ip pim rp-candidate loopback 0 int gi1/3 , gi 1/4 ip pim sparse-mode int gi 1/1 ip pim bsr-border

• Question 73:

  Which two specific characteristics categorize traceroute in an IPv6 routing environment? (Choose two.)

  A. Traceroute can show the path to reach any destination IPv6 address.
  B. Traceroute returns an error for a link-local IPv6 address.
  C. Traceroute is based on ICMPv6 Type 1 (Destination Unreachable) reply packets to determine the network path.
  D. Traceroute is based on ICMPv6 Type 3 (Time Exceeded) reply packets to determine the network path.
  E. Traceroute is based on ICMPv6 Type 2 (Packet Too Big) reply packets to determine the network path.
  F. Traceroute for IPv6 implements a backwards compatibility option to provide a detailed report in environments running dual-stack.
  A. Traceroute can show the path to reach any destination IPv6 address.
  D. Traceroute is based on ICMPv6 Type 3 (Time Exceeded) reply packets to determine the network path.

• Question 74:

  An SP core is running PIM on the network. Multicast groups in this network are in the 232.0.0.0/8 range. Which command enables multicast routing operations without using an RP?

  A. ip pim autorp
  B. ip pim ssm default
  C. ip pim bidir-enable
  D. ip pim register-source
  B. ip pim ssm default

• Question 75:

  DRAG DROP

  Select and Place:

  

  

• Question 76:

  

  Given the IPv6 address of 2001:0DB8::1:800:200E:88AA, what will be its corresponding the solicited-node multicast address?

  A. FF01::1:200E:88AA
  B. FF01::1:FF0E:88AA
  C. FF01:0DB8::1:800:200E:88AA
  D. FF02::1:FF0E:88AA
  E. FF02::1:200E:88AA
  F. FF02:0DB8::1:800:200E:88AA
  D. FF02::1:FF0E:88AA

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  IPv6 nodes (hosts and routers) are required to join (receive packets destined for) the following multicast groups: ꞏAll-nodes multicast group FF02:0:0:0:0:0:0:1 (scope is link-local) ꞏSolicited-node multicast group FF02:0:0:0:0:1:FF00:0000/104 for each of its assigned unicast and anycast addresses IPv6 routers must also join the all-routers multicast group FF02:0:0:0:0:0:0:2 (scope is link- local). The solicited-node multicast address is a multicast group that corresponds to an IPv6 unicast or anycast address. IPv6 nodes must join the associated solicitednode multicast group for every unicast and anycast address to which it is assigned. The IPv6 solicited-node multicast address has the prefix FF02:0:0:0:0:1: FF00:0000/104 concatenated with the 24 low-order bits of a corresponding IPv6 unicast or anycast address (see Figure 2). For example, the solicited-node multicast address corresponding to the IPv6 address 2037::01:800:200E:8C6C is FF02::1:FF0E:8C6C. Solicited-node addresses are used in neighbor solicitation messages

• Question 77:

  Which two statements regarding Auto RP operations and implementations are correct? (Choose two.)

  A. Candidate RPs send RP announcements to the 224.0.1.39 multicast group, and the mapping agents send RP discovery messages to the 224.0.1.40 multicast group
  B. Every PIM-SM router must be configured with the RP mapping agent IP address
  C. Candidate RPs learn the IP address of the mapping agents via periodic RP discovery messages
  D. Administrative scoping can be configured to limit the scope of the RP announcements
  E. A Reverse Path Forwarding check is done on the RP discovery messages
  F. RP discovery messages are flooded hop by hop throughout the network as multicast to the all PIM routers multicast group with a TTL of 1
  A. Candidate RPs send RP announcements to the 224.0.1.39 multicast group, and the mapping agents send RP discovery messages to the 224.0.1.40 multicast group
  D. Administrative scoping can be configured to limit the scope of the RP announcements

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  Auto-RP

  Automatic route processing (Auto-RP) is a feature that automates the distribution of group-to-RP mappings in a PIM network. This feature has these benefits:

  It is easy to use multiple RPs within a network to serve different group ranges.

  It allows load splitting among different RPs.

  It facilitates the arrangement of RPs according to the location of group participants. It avoids inconsistent, manual RP configurations that might cause connectivity

  problems. Multiple RPs can be used to serve different group ranges or to serve as hot backups for each other. To ensure that Auto-RP functions, configure routers

  as candidate RPs so that they can announce their interest in operating as an RP for certain group ranges. Additionally, a router must be designated as an RP-

  mapping agent that receives the RP-announcement messages from the candidate RPs, and arbitrates conflicts. The RPmapping agent sends the consistent

  group-to- RP mappings to all remaining routers. Thus, all routers automatically determine which RP to use for the groups they support auto-rp candidate-rp

  To configure a router as a Protocol Independent Multicast (PIM) rendezvous point (RP) candidate that sends messages to the well-known CISCO-RPANNOUNCE multicast group (224.0.1.39), use the auto-rp candidaterp command in PIM configuration mode. To return to the default behavior, use the no form of

  this command. auto-rp candidate-rp type interface-path-id scope ttl-value [ group-list access-listname ] [ interval seconds ] [bidir] no auto-rp candidate-rp type

  interface-path-id scope ttl-value [ group-list access-listname] [ interval seconds ] [bidir]

• Question 78:

  R1 is designated as the PIM RP within the SP core. Which two configuration parameters must be used to enable and activate R1 as the BSR and RP for the core environment? (Choose two.)

  A. ip pim send-rp-announce loopback0 scope 16
  B. ip pim bsr-candidate loopback0
  C. ip pim send-rp-discovery loopback0 scope 16
  D. ip pim rp-candidate loopback0
  E. ip pim send-RP-announce loopback0 scope 16 group-list 1
  B. ip pim bsr-candidate loopback0
  D. ip pim rp-candidate loopback0

• Question 79:

  

  Which additional feature is provided using MLDv2 that is not available in MLDv1?

  A. Multicast Address Specific Queries
  B. Source filtering
  C. Done messages
  D. Report messages
  B. Source filtering

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  PIM-SSM is made possible by IGMPv3 and MLDv2. Hosts can now indicate interest in specific sources using IGMPv3 and MLDv2. SSM does not require a rendezvous point (RP) to operate.

• Question 80:

  Which multicast implementation is preferred for traffic that is required by a small number of receivers across a large distributed network?

  A. DVMRP
  B. PIM-DM
  C. PIM-SM
  D. IGMP
  C. PIM-SM