Download New Latest (May) Cisco 642-883 Actual Tests 21-30

QUESTION 21

How can you prevent multihomed customers with connections to two service providers from acting as a transit AS?

A.	Enable BGP synchronization on all the customer routers
B.	Use MED to influence the inbound traffic from the ISPs
C.	Use static routing to the ISPs
D.	Use an AS-path access-list to filter the BGP updates to the ISPs
E.	Use conditional advertisements when sending BGP updates to the ISPs

Answer: D

QUESTION 22

What are two characteristics of the multihomed customers to service providers connection option? (Choose two.)

A.	Multihomed customers must use a private AS number.
B.	The traffic load can be shared for different destination networks between service providers.
C.	Multihomed customers must receive a full routing table from the service providers.
D.	The routing methodology must be capable of reacting to dynamic changes. BGP is used to achieve this flexibility.
E.	Multihomed customers must use a provider-assigned address space.

Answer: BD

QUESTION 23

What are two consequences of having constant link flaps, resulting in the OSPF neighbor adjacencies going up and down repeatedly? (Choose two.)

A.	routes getting into the “Stuck In Active” state
B.	constant flooding of LSAs
C.	OSPF route dampening to occur
D.	many SPF recalculations
E.	routing loops may temporarily be introduced into the network

< p class="MsoNormal" style="cursor: auto; margin: 0cm 0cm 0pt; line-height: normal; text-autospace: ; mso-pagination: none; mso-layout-grid-align: none">

Answer: BD

QUESTION 24

Which two OSPF network scenarios require OSPF virtual link configuration? (Choose two.)

A.	to connect an OSPF non-backbone area to area 0 through another non-backbone area
B.	to connect an NSSA area to an external routing domain
C.	to connect two parts of a partitioned backbone area through a non-backbone area
D.	to enable route leaking from Level 2 into Level 1
E.	to enable route leaking from Level 1 into Level 2
F.	to enable OSPF traffic engineering

Answer: AC

QUESTION 25

Which BGP attribute is a set of generic tags that can be used to signal various routing policies between BGP routers?

A.	AS path
B.	MED
C.	weight
D.	communities
E.	route tags

Answer: D

Explanation:http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example09186a00801 475b2.shtml

QUESTION 26

Refer to the exhibit.

Which two configuration options can be used to optimize the IS-IS network scenario? (Choose two.)

A.	Change the R1 and R2 IS type to Level 2.
B.	Change the R1 and R2 IS type to Level 1.
C.	Change the gi0/0 interface IS-IS circuit type on R1 and R2 to Level 2 only.
D.	Change the gi0/1 interface IS-IS circuit type on R1and R2 to Level 1.
E.	Change the IS type for all the routers to Level-1-2.
F.	Change the IS-IS network type for all the routers to point-to-point.

Answer: CD

QUESTION 27

What is the default OSPF seed metric and type?

A.	10 and E1
B.	10 and E2
C.	20 and E1
D.	20 and E2
E.	0 and E1
F.	0 and E2

Answer: D

QUESTION 28

Refer to the PE1 router routing table output exhibit.

What is causing the i su 10.1.10.0/24 [115/30] via 0.0.0.0, 00:40:34, Null0 entry on the PE1 router routing table?

A.	The PE1 router is receiving the 10.1.10.0/24 summary route from the upstream L1/L2 IS-IS router.
B.	The PE1 router has been configured to summarize the 10.1.10.x/32 IS-IS routes to 10.1.10.0/24.
C.	The 10.1.10.0/24 has been suppressed because IS-IS auto-summary has been disabled on the PE1 router.
D.	The 10.1.10.0/24 has been suppressed because of a route policy configuration on the PE1 router.
E.	The 10.1.10.0/24 has been suppressed because the more specific 10.1.10.x/32 IS-IS routes have been configured to leak into the IS-IS non-backbone area.

Answer: B

Explanation:

C:Documents and Settingsuser-nwzDesktop1.JPG

QUESTION 29

Which two statements regarding OSPFv2 or OSPFv3 authentication are correct? (Choose two.)

A.	OSPFv2 supports MD5 authentication.
B.	OSPFv2 supports MD5 or SHA authentication.
C.	OSPFv2 relies on the native security stack that uses IPsec.
D.	OSPFv3 supports MD5 authentication.
E.	OSPFv3 supports MD5 or SHA authentication.
F.	OSPFv3 relies on the native security stack that uses IPsec.