[PDF and VCE] Free Share 400-101 PDF Exam Preparation Materials with CertBus Real Exam Questions

CertBus 2018 Newest Cisco 400-101 CCIE Exam VCE and PDF Dumps for Free Download!

☆ 400-101 CCIE Exam PDF and VCE Dumps : 1063QAs Instant Download: https://www.certgod.com/400-101.html [100% 400-101 Exam Pass Guaranteed or Money Refund!!]
☆ Free view online pdf on CertBus free test 400-101 PDF: https://www.certgod.com/online-pdf/400-101.pdf
☆ CertBus 2018 Newest 400-101 CCIE exam Question PDF Free Download from Google Drive Share: https://drive.google.com/file/d/0B_3QX8HGRR1mdEpkTFZvSDJDc2c/view?usp=sharing

Following 400-101 1063QAs are all new published by Cisco Official Exam Center

No doubt that CCIE Apr 08,2018 Latest 400-101 pdf dumps exam is a tough task to accomplish. But you should not feel hesitant against the confronting difficulties. CertBus provides the latest version of Newest 400-101 pdf dumps CCIE Routing and Switching Written v5.0 VCE dumps. Get a complete hold on CCIE Hotest 400-101 study guide exam syllabus through CertBus and boost up your skills. Besides, the Cisco dumps are the latest. It would be great helpful to your CCIE Latest 400-101 exam questions CCIE Routing and Switching Written v5.0 exam.

CertBus 100% accurate exam brain dumps with latest update. download the free 400-101 demo to check first. CertBus – leader of 400-101 certifications, latest dumps, guaranteed pass. pass 400-101 exam | 400-101 written test | 400-101 exam study guide | 400-101 exam tips. CertBus latest 400-101 exam dumps questions and answers in pdf format.

We CertBus has our own expert team. They selected and published the latest 400-101 preparation materials from Cisco Official Exam-Center: https://www.certgod.com/400-101.html

QUESTION NO:7

Which statement is true about TCN propagation?

A. The originator of the TCN immediately floods this information through the network.

B. The TCN propagation is a two step process.

C. A TCN is generated and sent to the root bridge.

D. The root bridge must flood this information throughout the network.

Answer: C

Explanation:

Explanation

New Topology Change Mechanisms

When an 802.1D bridge detects a topology change, it uses a reliable mechanism to first notify the

root bridge.

This is shown in this diagram:

Once the root bridge is aware of a change in the topology of the network, it sets the TC flag on the

BPDUs it sends out, which are then relayed to all the bridges in the network. When a bridge

receives a BPDU with the TC flag bit set, it reduces its bridging-table aging time to forward delay

seconds. This ensures a relatively quick flush of stale information. Refer to Understanding

Spanning-Tree Protocol Topology Changes for more information on this process. This topology

change mechanism is deeply remodeled in RSTP. Both the detection of a topology change and its

propagation through the network evolve.

Topology Change Detection

In RSTP, only non-edge ports that move to the forwarding state cause a topology change. This

means that a loss of connectivity is not considered as a topology change any more, contrary to

802.1D (that is, a port that moves to blocking no longer generates a TC). When a RSTP bridge

detects a topology change, these occur:

It starts the TC While timer with a value equal to twice the hello-time for all its non-edge

designated ports and its root port, if necessary.

It flushes the MAC addresses associated with all these ports.

Note: As long as the TC While timer runs on a port, the BPDUs sent out of that port have the TC

bit set.

BPDUs are also sent on the root port while the timer is active.

Topology Change Propagation

When a bridge receives a BPDU with the TC bit set from a neighbor, these occur:

It clears the MAC addresses learned on all its ports, except the one that receives the topology

change.

It starts the TC While timer and sends BPDUs with TC set on all its designated ports and root port

(RSTP no longer uses the specific TCN BPDU, unless a legacy bridge needs to be notified).

This way, the TCN floods very quickly across the whole network. The TC propagation is now a one

step process. In fact, the initiator of the topology change floods this information throughout the

network, as opposed to 802.1D where only the root did. This mechanism is much faster than the

802.1D equivalent. There is no need to wait for the root bridge to be notified and then maintain the

topology change state for the whole network for seconds.

In just a few seconds, or a small multiple of hello-times, most of the entries in the CAM tables of

the entire network (VLAN) flush. This approach results in potentially more temporary flooding, but

on the other hand it clears potential stale information that prevents rapid connectivity restitution.

Reference

http://www.cisco.com/en/US/tech/tk389/tk621/technologies_white_paper09186a0080094cfa.shtml

QUESTION NO:13

Which two statements are true about traffic shaping? (Choose two.)

A. Out-of-profile packets are queued.

B. It causes TCP retransmits.

C. Marking/remarking is not supported.

D. It does not respond to BECN and ForeSight Messages.

E. It uses a single/two-bucket mechanism for metering.

Answer: A,C

Explanation:

QUESTION NO:17

Which three combinations are valid LACP configurations that will set up a channel? (Choose

three.)

A. On/On

B. On/Auto

C. Passive/Active

D. Desirable/Auto

E. Active/Active

F. Desirable/Desirable

Answer: A,C,E

Explanation:

QUESTION NO:19

Which two options does Cisco PfR use to control the entrance link selection with inbound

optimization? (Choose two.)

A. Prepend extra AS hops to the BGP prefix.

B. Advertise more specific BGP prefixes (longer mask).

C. Add (prepend) one or more communities to the prefix that is advertised by BGP.

D. Have BGP dampen the prefix.

Answer: A,C

Explanation: PfR Entrance Link Selection Control Techniques

The PfR BGP inbound optimization feature introduced the ability to influence inbound traffic. A

network advertises reachability of its inside prefixes to the Internet using eBGP advertisements to

its ISPs. If the same prefix is advertised to more than one ISP, then the network is multihoming.

PfR BGP inbound optimization works best with multihomed networks, but it can also be used with

a network that has multiple connections to the same ISP. To implement BGP inbound

optimization, PfR manipulates eBGP advertisements to influence the best entrance selection for

traffic bound for inside prefixes. The benefit of implementing the best entrance selection is limited

to a network that has more than one ISP connection.

To enforce an entrance link selection, PfR offers the following methods:

BGP Autonomous System Number Prepend When an entrance link goes out-of-policy (OOP) due

to delay, or in images prior to Cisco IOS Releases 15.2(1) T1 and 15.1(2)S, and PfR selects a

best entrance for an inside prefix, extra autonomous system hops are prepended one at a time (up

to a maximum of six) to the inside prefix BGP advertisement over the other entrances. In Cisco

IOS Releases 15.2(1)T1, 15.1(2)S, and later releases, when an entrance link goes out-of policy

(OOP) due to unreachable or loss reasons, and PfR selects a best entrance for an inside prefix,

six extra autonomous system hops are prepended immediately to the inside prefix BGP

advertisement over the other entrances. The extra autonomous system hops on the other

entrances increase the probability that the best entrance will be used for the inside prefix. When

the entrance link is OOP due to unreachable or loss reasons, six extra autonomous system hops

are added immediately to allow the software to quickly move the traffic away from the old entrance

link. This is the default method PfR uses to control an inside prefix, and no user configuration is

required.

BGP Autonomous System Number Community Prepend

When an entrance link goes out-of-policy (OOP) due to delay, or in images prior to Cisco IOS

Releases 15.2

(1)T1 and 15.1(2)S, and PfR selects a best entrance for an inside prefix, a BGP prepend

community is attached one at a time (up to a maximum of six) to the inside prefix BGP

advertisement from the network to another autonomous system such as an ISP. In Cisco IOS

Releases 15.2(1)T1, 15.1(2)S, and later releases, when an entrance link goes out-of-policy (OOP)

due to unreachable or loss reasons, and PfR selects a best entrance for an inside prefix, six BGP

prepend communities are attached to the inside prefix BGP advertisement. The BGP prepend

community will increase the number of autonomous system hops in the advertisement of the

inside prefix from the ISP to its peers. Autonomous system prepend BGP community is the

preferred method to be used for PfR BGP inbound optimization because there is no risk of the

local ISP filtering the extra autonomous system hops. There are some issues, for example, not all

ISPs support the BGP prepend community, ISP policies may ignore or modify the autonomous

system hops, and a transit ISP may filter the autonomous system path. If you use this method of

inbound optimization and a change is made to an autonomous system, you must issue an

outbound reconfiguration using the “clear ip bgp” command.

Reference

http://www.cisco.com/en/US/docs/ios-xml/ios/pfr/configuration/15-2s/pfr-bgp-inbound.html#GUID-

F8A59E241D59-

4924-827D-B23B43D9A8E0

http://www.cisco.com/en/US/products/ps8787/products_ios_protocol_option_home.html

QUESTION NO:22

Refer to the exhibit.

Which path is selected as best path?

A. path 1, because it is learned from IGP B.

path 1, because the metric is the lowest C.

path 2, because it is external

D. path 2, because it has the higher router ID

Answer: B

Explanation:

400-101 PDF Dumps400-101 Exam Questions400-101 Braindumps

QUESTION NO:23

What action will a BGP route reflector take when it receives a prefix marked with the community

attribute NO ADVERTISE from a client peer?

A. It will advertise the prefix to all other client peers and non-client peers.

B. It will not advertise the prefix to EBGP peers.

C. It will only advertise the prefix to all other IBGP peers.

D. It will not advertise the prefix to any peers.

Answer: D

Explanation:

QUESTION NO:24

Refer to the exhibit.

R1 is not learning about the 172.16.10.0 subnet from the BGP neighbor R2 (209.165.202.130).

What can be done so that R1 will learn about this network?

A. Disable auto-summary on R2.

B. Configure an explicit network command for the 172.16.10.0 subnet on R2.

C. Subnet information cannot be passed between IBGP peers.

D. Disable auto-summary on R1.

Answer: B

Explanation:

By default, BGP does not accept subnets redistributed from IGP. To advertise and carry subnet

routes in BGP, use an explicit network command or the no auto-summary command. If you disable

auto-summarization and have not entered a network command, you will not advertise network

routes for networks with subnet routes unless they contain a summary route.

Reference

http://www.cisco.com/en/US/docs/ios/11_3/np1/command/reference/1rbgp.html

QUESTION NO:27

Refer to the exhibit.

What triggered the first SPF recalculation?

A. changes in a router LSA, subnet LSA, and external LSA

B. changes in a router LSA, summary network LSA, and external LSA

C. changes in a router LSA, summary network LSA, and summary ASBR LSA

D. changes in a router LSA, summary ASBR LSA, and external LSA

Answer: B

Explanation:

OSPFv2

Is built around links, and any IP prefix change in an area will trigger a full SPF. It advertises IP

information in Router and Network LSAs. The routers thus, advertise both the IP prefix information

(or the connected subnet information) and topology information in the same LSAs. This implies

that if an IP address attached to an interface changes, OSPF routers would have to originate a

Router LSA or a Network LSA, which btw also carries the topology information. This would trigger

a full SPF on all routers in that area, since the same LSAs are flooded to convey topological

change information. This can be an issue with an access router or the one sitting at the edge,

since many stub links can change regularly.

Only changes in interarea, external and NSSA routes result in partial SPF calculation (since type

3, 4, 5 and 7 LSAs only advertise IP prefix information) and thus IS-IS

QUESTION NO:30

What is the flooding scope of an OSPFv3 LSA, if the value of the S2 bit is set to 1 and the S1 bit is

set to 0?

A. link local

B. area wide

C. AS wide

D. reserved

Answer: C

Explanation:

The Type 1 router LSA is now link local and the Type 2 Network LSA is AS Wide

S2 and S1 indicate the LSA’s flooding scope. Table 9-1 shows the possible values of these two

bits and the associated flooding scopes.

Table 9-1 S bits in the OSPFv3 LSA Link State Type field and their associated flooding scopes

LSA Function Code, the last 13 bits of the LS Type field, corresponds to the OSPFv2 Type field.

Table 9-2 shows the common LSA types used by OSPFv3 and the values of their corresponding

LS Types. If you decode the hex values, you will see that the default U bit of all of them is 0. The S

bits of all LSAs except two indicate area scope. Of the remaining two, AS External LSAs have an

AS flooding scope and Link LSAs have a linklocal flooding scope. Most of the OSPFv3 LSAs have

functional counterparts in OSPFv2; these OSPFv2 LSAs and their types are also shown in Table

9-2.

Table 9-2 OSPFv3 LSA types and their OSPFv2 counterparts

Reference

http://www.networkworld.com/subnets/cisco/050107-ch9-ospfv3.html?page=1

QUESTION NO:34

In order to maintain security, with which hop count are IPv6 neighbor discovery packets sent?

A. 0

B. 1

C. 255

D. 256

Answer: C

Explanation:

CertBus exam braindumps are pass guaranteed. We guarantee your pass for the 400-101 exam successfully with our Cisco materials. CertBus CCIE Routing and Switching Written v5.0 exam PDF and VCE are the latest and most accurate. We have the best Cisco in our team to make sure CertBus CCIE Routing and Switching Written v5.0 exam questions and answers are the most valid. CertBus exam CCIE Routing and Switching Written v5.0 exam dumps will help you to be the Cisco specialist, clear your 400-101 exam and get the final success.

400-101 Latest questions and answers on Google Drive(100% Free Download): https://drive.google.com/file/d/0B_3QX8HGRR1mdEpkTFZvSDJDc2c/view?usp=sharing

400-101 Cisco exam dumps (100% Pass Guaranteed) from CertBus: https://www.certgod.com/400-101.html [100% Exam Pass Guaranteed]

Why select/choose CertBus?

Millions of interested professionals can touch the destination of success in exams by certgod.com. products which would be available, affordable, updated and of really best quality to overcome the difficulties of any course outlines. Questions and Answers material is updated in highly outclass manner on regular basis and material is released periodically and is available in testing centers with whom we are maintaining our relationship to get latest material.

Brand	Certbus	Testking	Pass4sure	Actualtests	Others
Price	$45.99	$124.99	$125.99	$189	$69.99-99.99
Up-to-Date Dumps
Free 365 Days Update
Real Questions
Printable PDF
Test Engine
One Time Purchase
Instant Download
Unlimited Install
100% Pass Guarantee
100% Money Back
Secure Payment
Privacy Protection