Finding Most up-to-date 400-101 secret

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Q81. Which algorithm heavily influenced the algorithm used by path-vector protocols? 

A. Bellman-Ford 



D. Spanning-Tree 

E. Adaptive 

F. Deflection 



A path vector protocol is a computer network routing protocol which maintains the path information that gets updated dynamically. Updates which have looped through the network and returned to the same node are easily detected and discarded. This algorithm is sometimes used in Bellman–Ford routing algorithms to avoid "Count to Infinity" problems. 


Q82. Which type of port would have root guard enabled on it? 

A. A root port 

B. An alternate port 

C. A blocked port 

D. A designated port 



The root guard feature provides a way to enforce the root bridge placement in the network. The root guard ensures that the port on which root guard is enabled is the designated port. Normally, root bridge ports are all designated ports, unless two or more ports of the root bridge are connected together. If the bridge receives superior STP Bridge Protocol Data Units (BPDUs) on a root guard-enabled port, root guard moves this port to a root-inconsistent STP state. This root-inconsistent state is effectively equal to a listening state. No traffic is forwarded across this port. In this way, the root guard enforces the position of the root bridge. 


Q83. Refer to the exhibit. 

Which two statements are true? (Choose two.) 

A. This is the output of the show ip ospf command. 

B. This is the output of the show ip protocols command. 

C. This router is an ABR. 

D. This router is an ASBR. 

E. Authentication is not configured for the area. 

Answer: A,E 


The following is sample output from the show ip ospf command when entered without a specific OSPF process ID with no authentication. 

Router# show ip ospf 

Routing Process "ospf 201" with ID and Domain ID 

Supports only single TOS(TOS0) routes 

Supports opaque LSA 

SPF schedule delay 5 secs, Hold time between two SPFs 10 secs 

Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs 

LSA group pacing timer 100 secs 

Interface flood pacing timer 55 msecs 

Retransmission pacing timer 100 msecs 

Number of external LSA 0. Checksum Sum 0x0 

Number of opaque AS LSA 0. Checksum Sum 0x0 

Number of DCbitless external and opaque AS LSA 0 

Number of DoNotAge external and opaque AS LSA 0 

Number of areas in this router is 2. 2 normal 0 stub 0 nssa 

External flood list length 0 


Number of interfaces in this area is 2 

Area has no authentication 

SPF algorithm executed 4 times 

Area ranges are 

Number of LSA 4. Checksum Sum 0x29BEB 

Number of opaque link LSA 0. Checksum Sum 0x0 

Number of DCbitless LSA 3 Number of indication LSA 0 

Number of DoNotAge LSA 0 Flood list length 0 


Q84. Which AS_PATH attribute can you use to prevent loops when implementing BGP confederations? 






Q85. Which option describes the purpose of the leak-map keyword in the command eigrp stub connected leak-map EigrpLeak? 

A. It allows the specified static routes to be advertised. 

B. It allows exceptions to the route summarization that is configured. 

C. It allows specified EIGRP-learned routes to be advertised. 

D. It restricts specified connected routes from being advertised. 



ExamplE. eigrp stub leak-map Command 

In the following example, the eigrp stub command is issued with the leak-map name keyword-argument pair to configure the device to reference a leak map that identifies routes to be advertised that would have been suppressed otherwisE. 

Device(config)# router eigrp 1 

Device(config-router)# network 

Device(config-router)# eigrp stub leak-map map1 



Drag and drop the PPPoE packet type on the left to the corresponding description on the right. 



Drag and drop the Cisco IOX XE subpackage on the left to the function it performs on the right. 


Q88. Refer to the exhibit. 

Which two routes are included in the route update? (Choose two.) 






Answer: C,D 


This access list will permit the,,, and subnets. 

Q89. Which option is the Cisco recommended method to secure access to the console port? 

A. Configure the activation-character command. 

B. Configure a very short timeout (less than 100 milliseconds) for the port. 

C. Set the privilege level to a value less than 15.

D. Configure an ACL. 



The activation-character command defines a session activation character. Entering this character at a vacant terminal begins a terminal session. The default activation character is the Return key 

To secure the console port, you should change this character to a different one as most people simply hit the enter key when trying to access the console. 

Q90. Which two options are requirements for Control-Plane Policing? (Choose two.) 

A. Cisco Express Forwarding must be enabled globally. 

B. Cisco Discovery Protocol must be disabled in the control plane. 

C. A crypto policy must be installed. 

D. A loopback address must be configured for device access. 

E. A class map must be configured to identify traffic. 

Answer: A,E