Cisco 642-885 Online Practice Questions and Exam Preparation

Cisco 642-885 Online Questions & Answers

• Question 111:

  Which of the following can be used by dual-stack service providers supporting IPv4/IPv6 customers with dual-stack hosts using public IPv6 addresses and private IPv4 addresses?

  A. NAT64
  B. 6RD
  C. 6to4 tunnels
  D. Carrier-grade NAT
  D. Carrier-grade NAT

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  Carrier Grade NAT is a large-scale NAT, capable of providing private-IPv4-to-public-IPv4 translation in the order of millions of translations. Carrier Grade NAT can support several hundred thousand subscribers with the bandwidth throughput of at least 10Gb/s full-duplex. With IPv4 addresses reaching depletion, Carrier Grade NAT is vital in providing private IPv4 connectivity to the public IPv4 internet. In addition, Carrier Grade NAT is not limited to IPv4 NAT; it can also translate between IPv4 and IPv6 addresses.

• Question 112:

  Which option shows the equivalent multicast MAC address mapping of multicast address 239.210.101.190?

  A. 01:00:5e:52:65:be
  B. 01:00:5d:52:65:be
  C. 01:00:5f:52:65:be
  D. 01:00:5c:52:65:be
  A. 01:00:5e:52:65:be

• Question 113:

  Which type of BGP session behaves like an EBGP session during session establishment but behaves like an IBGP session when propagating routing updates where the local preference, multi-exit discriminator, and next-hop attributes are not changed?

  A. BGP sessions between a route reflector and its clients
  B. BGP sessions between a route reflector and its non-client IBGP peers
  C. BGP sessions between a route reflector and another route reflector
  D. Intra-confederation IBGP sessions
  E. Intra-confederation EBGP sessions
  E. Intra-confederation EBGP sessions

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  http://www.cisco.com/en/US/docs/ios_xr_sw/iosxr_r3.7/routing/configuration/guide/rc37bgp.ht ml#wp1191371

  BGP Routing Domain Confederation One way to reduce the iBGP mesh is to divide an autonomous system into multiple subautonomous systems and group them into a single confederation. To the outside world, the confederation looks like a single autonomous system. Each autonomous system is fully meshed within itself and has a few connections to other autonomous systems in the same confederation. Although the peers in different autonomous systems have eBGP sessions, they exchange routing information as if they were iBGP peers. Specifically, the next hop, MED, and local preference information is preserved. This feature allows you to retain a single IGP for all of the autonomous systems.

• Question 114:

  Which two functions are supported for BGP extension MP-BGP for IP multicasting? (Choose two.)

  A. A network can support incongruent unicast and multicast topologies.
  B. A network can support congruent unicast and multicast topologies.
  C. MP-BGP is an enhanced BGP that carries routing information for multiple network layer protocols and IP multicast routes.
  D. MP-BGP carries single sets of routes for unicast routing and multicast routing.
  E. MP-BGP is useful when a link dedicated to multicast and unicast traffic is desired.
  A. A network can support incongruent unicast and multicast topologies.
  C. MP-BGP is an enhanced BGP that carries routing information for multiple network layer protocols and IP multicast routes.

• Question 115:

  Which multicast routing protocol supports dense mode, sparse mode and bidirectional mode?

  A. DVMRP
  B. MOSPF
  C. PIM
  D. MP-BGP E. MSDP
  C. PIM

• Question 116:

  When verifying multicast configurations and operations on Cisco IOS-XR routers, which two statements regarding show commands are correct? (Choose two.)

  A. Use the show route ipv4 multicast command to display the incoming and outgoing interface lists for each of the joined multicast groups
  B. Use the show pim rpf command to display the RPF information for the RP or for the multicast source
  C. Use the show mrib route command to display the (*, G) and (S, G) states information on the router
  D. Use the show mrib route command to display the configured static multicast routes
  B. Use the show pim rpf command to display the RPF information for the RP or for the multicast source
  C. Use the show mrib route command to display the (*, G) and (S, G) states information on the router

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• Question 117:

  When implementing Anycast RP, the RPs are also required to establish which kind of peering with each other?

  A. BGP
  B. Multiprotocol BGP
  C. MSDP
  D. Bidirectional PIM
  E. PIM SSM
  C. MSDP

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  http://www.cisco.com/en/US/docs/ios/solutions_docs/ip_multicast/White_papers/anycast.html

  Using Anycast RP is an implementation strategy that provides load sharing and redundancy in Protocol Independent Multicast sparse mode (PIM-SM) networks. Anycast RP allows two or more rendezvous points (RPs) to share the load for source registration and the ability to act as hot backup routers for each other. Multicast Source Discovery Protocol (MSDP) is the key protocol that makes Anycast RP possible.

• Question 118:

  Assume that the R1 router is enabled for PIM-SM and receives a multicast packet sourced from 172.16.1.100, and the R1 router has multicast receivers on the Gi0/1, Gi0/2, Gi0/3 and Gi0/4 interfaces.

  

  The multicast packet from the 172.16.1.100 source must arrive on which interface on the R1 router for it to be forwarded out the other interfaces?

  A. Gi0/1
  B. Gi0/2
  C. Gi0/3
  D. Gi0/4
  E. Gi0/1 or Gi0/2 or Gi0/3 or Gi0/4
  F. Gi0/2 or Gi0/3
  G. Gi0/1 or Gi0/4
  A. Gi0/1

• Question 119:

  Which information does the multicast supported router need to forward the multicast traffic over the source or shared tree?

  A. source address
  B. multicast address
  C. destination address
  D. mGRE headers
  E. MDT Data
  C. destination address

• Question 120:

  Which multicast routing protocol is used to forward multicast data along the optimal path from source to receivers?

  A. PIM DM
  B. PIM Bi-Dir
  C. PIM SM
  D. SSM
  E. IGMP
  F. MSDP
  C. PIM SM