NEW QUESTION 1
The Cisco IOS and IOS XE qos pre-classify command allows which kind of packet classification on IP packets that are encapsulated with GRE and IPsec?

• A. allows for packets to be classified based on the ToS byte values before packet encryption
• B. allows for packets to be classified based on the ToS byte values after packet encryption
• C. allows for packets to be classified based on the packet payload before packet encryption
• D. allows for packets to be classified based on the packet payload after packet encryption
• E. allows for packets to be classified based on the packet header parameters other than the ToS byte values after packet encryption

Answer: E

NEW QUESTION 2
Which two advantages are reasons that service providers might deploy MPLS? (Choose two.)

• A. to avoid using IGP in the core
• B. to facilitate smooth migrations between legacy WAN technologies
• C. to reduce the throughput overhead of full IPv4/IPv6 headers when traversing the core
• D. to reduce the computational requirements that are placed on router CPUs
• E. to reduce configuration and feature requirements in the core

Answer: CD

NEW QUESTION 3
Which two of the following statements are correct regarding LSPs? (Choose two.)

• A. An LSP is created for every routing protocol entry.
• B. Each LSP is bidirectional, that is, packets traveling in the opposite direction use the same LSP.
• C. An IGP is used to populate routing tables in all routers in an MPLS domain.
• D. LDP is used to propagate labels and build LSPs.
• E. The FIB is used to forward MPLS-labeled packets down an LSP.

Answer: CD

NEW QUESTION 4
An engineer has been tasked to configure a guaranteed 2 Mbps of bandwidth for outgoing FTP traffic on interface FastEthernet 1/1/1 on Cisco IOS XR. Which method accomplishes this configuration?

• A. configure terminal class-map FTP_CLASS match protocol ftpexitpolicy-map POLICY_1 class FTP_CLASS bandwidth 2000exit exitinterface FastEthernet 1/1/1 service-policy output POLICY_1 endcommit
• B. configure terminal class-map FTP_CLASS match protocol ftpexitpolicy-map POLICY_1 class FTP_CLASS bandwidth 2000000 exitexitinterface FastEthernet 1/1/1 service-policy input POLICY_1 endcommit
• C. configure terminalaccess-list 100 permit ip any any eq 21 policy-map POLICY_1match ip access-list 100 bandwidth 2000exit exitinterface FastEthernet 1/1/1 service-policy output POLICY_1 endcommit
• D. configure terminal policy-map POLICY_1 class FTP_CLASS match protocol ftp bandwidth 2000000 exitexitinterface FastEthernet 1/1/1 service-policy input POLICY_1 endcommit

Answer: A

NEW QUESTION 5
The regional operation center deploys a Cisco MPLS TE tunnel over the company's core network. The Cisco MPLS TE tunnel is up and no error is detected, but no traffic is traversing the tunnel. Which two issues are possible causes? (Choose two.)

• A. The provider edge router is not performing the correct redistribution.
• B. The interior gateway protocol has no knowledge of the Cisco MPLS TE tunnel.
• C. No static route has been defined to route data traffic over the Cisco MPLS TE tunnel.
• D. The customer edge router is injecting rogue IPv4 prefixes in the provider edge routing table.
• E. The end-to-end label switched path has not been established.

Answer: BC

NEW QUESTION 6
An LDP session is established between two neighbors. Over which protocol and port number do they maintain their adjacency?

• A. TCP 711
• B. UDP 646
• C. UDP 711
• D. TCP 646

Answer: D

NEW QUESTION 7
When configuring class-based WRED on Cisco routers, which WRED parameter is not user configurable on a Cisco IOS XR but is user configurable on a Cisco IOS and IOS XE?

• A. the ingress or egress direction where the class-based WRED policy will be applied
• B. the maximum threshold
• C. the minimum threshold
• D. the mark probability denominator

Answer: D

Explanation: Comparison of Cisco IOS QoS and Cisco IOS-XR QoS
The Cisco IOS-XR software implementation of QoS is basically the same as the QoS implementation on Cisco
IOS software, with the following exceptions:
•On Cisco IOS-XR software, the bandwidth command can be configured only in egress policies.
•The following changes have been made to the class-map command on Cisco IOS-XR software:
–Supports 4K per logical router.
–Maximum number of match criteria configurable in one class map is eight.
•When a class is marked as high priority using the priority command on Cisco IOS-XR software, we recommend that you configure a policer to limit the priority traffic. Limiting the priority traffic will ensure that the priority traffic does not starve all of the other traffic on the line card. Use the police command to explicitly configure the policer.
•On Cisco IO-XR software, only one conform-action, exceed-action, or violate-action command can be configured at a time. To configure traffic policing, use the police command.
•On Cisco IOS-XR software, policy modifications cannot be made on existing policies. Use the policy-map command to remove the policy from all attached interfaces, delete the policy map, and redefine a new policy.
•When configuring a policy map on Cisco IOS-XR software, the maximum number of classes configurable in one policy map is 16, which includes both Level 1 and Level 2 classes. To configure a policy map, use the policy-map command.
•When WRED is configured on Cisco IOS-XR software, the mark probability in the random- detect command is not configurable—it is always set to 1.
•When the random-detect exp command is used on Cisco IOS-XR software, the exponential weighting constant is not configurable and will be programmed automatically by Cisco IOS-XR software.
•When access control lists (ACLs) are used in QoS class maps, the underlying deny or permit actions associated with access control entries (ACEs) are ignored. ACEs are used as a classification mechanism in order to provide appropriate QoS behavior as specified in class maps. Use ACLs that include ACEs with permit actions only.

NEW QUESTION 8
A network engineer wants to implement QoS in an environment in which GRE tunnels are used. The engineer creates a policy map to classify the traffic and applies the map to the physical interface. Despite a successful ping to the end of the tunnel, the counter of the class-map ICMP does not register a hit. How can the engineer fix this problem?

• A. enable QoS preclassify in the tunnel interface
• B. send the ping with source tunnel 0
• C. send the ping with source F0/0
• D. enable QoS preclassify in the physical interface

Answer: A

NEW QUESTION 9
On a Cisco router, when will the router actually reserve the bandwidth for the MPLS traffic engineering tunnel?

• A. during the autoroute process
• B. during constraint-based routing calculations
• C. on the receipt of the RSVP Path message
• D. on the receipt of the RSVP Resv message

Answer: D

NEW QUESTION 10
DRAG DROP

Answer:

Explanation: RSVP PATH Message --- sent from the tunnel headend to the tunnel tailend
---- carried the MPLS label requests
RSVP RESV Message—Sent from the tunnel tailend to the tunnel headend
--- carries the MPLS lables
RSVP PATH Message --- sent from the tunnel head end to the tunnel tail end ---- carried the MPLS label requests
RSVP RESV Message--Sent from the tunnel tail end to the tunnel head end --- carries the MPLS labels

NEW QUESTION 11
Which three commands are used to troubleshoot why IP packets are not forwarded on the LSP? (Choose three.)

• A. show cef prefix/length to check the prefix information
• B. debug mpls ldp transport events to display events related to the LDP peer discovery mechanism
• C. show mpls forwarding labels <label-id> hardware egress location <node-id> to check the hardware label FIB
• D. show arp <prefix> location <node-id> for the next hop prefix
• E. show mpls ldp discovery for the corresponding label information
• F. debug mpls ea platform all to display MPLS setup events and errors

Answer: ACD

NEW QUESTION 12
Which option describes the IPv6 flow label field?

• A. a 3-bit field used for marking a traffic flow
• B. an 8-bit field used for labeling a traffic flow
• C. a 20-bit field used to tag a traffic flow throughout the network
• D. an 8-bit field out of which the first 6 are used to classify packets

Answer: C

NEW QUESTION 13
A company is experiencing congestion on Internet T1 links that transport site-to-site IPsec tunnels between head offices. QoS configuration is being modified on these T1 links. Which option describes the result from this QoS configuration?

• A. VPN traffic is unaffected because the inner ToS field is encrypted and hidden from the policy
• B. The physical interface is affected by the new QoS configuration
• C. The internal VPN logical interface reflects the new QoS service policy
• D. IPsec protocol applications work independently of the QoS configuration

Answer: A

NEW QUESTION 14
On the Cisco ASR9K router, when using the bandwidth command to specify the minimum guaranteed bandwidth to be allocated for a specific class of traffic, what will be used as the queuing algorithm?

• A. custom queuing
• B. CBWFQ
• C. WFQ
• D. FIFO
• E. priority queuing

Answer: B

Explanation: Class based weighted fair queuing (CB-WFQ) was initially released without the support of a priority queuing system, thus it could not guarantee the delay and jitter (delay variation) requirements of real-time, interactive voice and video conversations. Since for CBWFQ, the weight for a packet belonging to a specific class is derived from the bandwidth assigned to the class, which in turn determines the order in which packets are sent.
All packets are serviced fairly based on weight and no class of packets may be granted strict priority. This scheme poses problems for voice traffic that is largely intolerant of delay, especially variation in delay

NEW QUESTION 15
Which QoS technique can be used to protect customer traffic from being dropped by traffic rate limiting performed by the service provider?

• A. LLQ
• B. policing
• C. fair-queue
• D. shaping

Answer: D

NEW QUESTION 16
When implementing Cisco MPLS TE, the constrained-based path calculations will use which value as the TE cost of each link within the MPLS domain?

• A. By default, it will use the IGP metric, or each link can be assigned a specific value using the admin-weight command.
• B. It can only use the IGP metric as the TE cost.
• C. It will use the interface bandwidth as the TE cost.
• D. Each link must be assigned a TE cost using the metric command.

Answer: A

NEW QUESTION 17
Which two statements are correct in describing ISP environments that are running IP/MPLS in the core network? (Choose two.)

• A. On the PE routers, each BGP route must use a unique label to reach the BGP next hop.
• B. The BGP next hops point to the PE routers, and only the PE routers are required to run BGP.
• C. A full mesh of IBGP sessions are required between all of the PE and P routers to ensure proper packets forwarding.
• D. The PE and P routers run LDP to learn the labels for reaching the BGP next-hop addresses.

Answer: BD

NEW QUESTION 18
Which are typical class-based marking policies that are implemented on service provider IP NGN PE routers?

• A. On the PE ingress, classify the customer traffic and then mark with qos-grou
• B. On the PE egress, classify based on the qos-group and then mark with mpls exp.
• C. On the PE ingress, classify the customer traffic and then mark with mpls ex
• D. On the PE egress, classify based on the mpls exp and then mark with qos-group.
• E. On the PE ingress, trust the customer QoS marking
• F. On the PE egress, classify based on the customer QoS markings and then mark with qos-group.
• G. On the PE ingress, trust the customer QoS marking
• H. On the PE egress, classify based on the customer QoS markings and then mark with mpls exp.

Answer: A