Cisco 642-885 Dumps To Pass Exam

These 642-885 dumps PDF format works on your digital devices and gives you maximum knowledge to achieve excellent marks. These 642-885 dumps PDF format is compatible with your smartphones, PC and laptops. The CCNP Service Provider Certification is one of the respected certification and recognizes skills to configure and optimize service provider IP next-generation network infrastructures.

Try it Latest DumpsSchool 642-885 Exam dumps. Buy Full File here: (131 As Dumps)

Download the DumpsSchool 642-885 braindumps from Google Drive: (FREE VERSION!!!)

Question No. 1

Refer to the topology diagram shown in the exhibit and the partial configurations shown below.

Once the attack from to has been detected, which additional configurations are required on the P1 IOS-XR router to implement source-based remote-triggered black hole filtering?


router bgp 123

address-family ipv4 unicast

redistribute static route-policy test


Answer: C

Source-Based RTBH Filtering

With destination-based black holing, all traffic to a specific destination is dropped after the black hole has been activated, regardless of where it is coming from. Obviously, this could include legitimate traffic destined for the target. Source-based black holes provide the ability to drop traffic at the network edge based on a specific source address or range of source addresses.

If the source address (or range of addresses) of the attack can be identified (spoofed or not), it would be better to drop all traffic at the edge based on the source address, regardless of the destination address. This would permit legitimate traffic from other sources to reach the target. Implementation of source-based black hole filtering depends on Unicast Reverse Path Forwarding (uRPF), most often loose mode uRPF. Loose mode uRPF checks the packet and forwards it if there is a route entry for the source IP of the incoming packet in the router forwarding information base (FIB). If the router does not have an FIB entry for the source

IP address, or if the entry points to a null interface, the Reverse Path Forwarding (RPF) check fails and the packet is dropped, as shown in Figure 2. Because uRPF validates a source IP address against its FIB entry, dropping traffic from specific source addresses is accomplished by configuring loose mode uRPF on the external interface and ensuring the RPF check fails by inserting a route to the source with a next hop of Null0. This can be done by using a trigger device to send IBGP updates. These updates set the next hop for the source IP to an unused IP address that has a static entry at the edge, setting it to null as shown in Figure 2.

Question No. 2


On the PE5 router, which statement is correct regarding the learned BGP prefixes?

Answer: C

#show ip bgp — check i tag for PE5

Question No. 3

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

Answer: A, C

Question No. 4

Which four operations are components of MSDP in interdomain multicast setup? (Choose four.)

Answer: C, D, E, F

Question No. 5

What must occur before an (S,G) entry can be populated in the multicast routing table?

Answer: D

642-885 Dumps Google Drive: (Limited Version!!!)

Related Certification: CCNP Service Provider dumps

Leave a Reply

Your email address will not be published. Required fields are marked *