Q1. A network engineer initiates the ip sla responder tcp-connect command in order to gather statistics for performance gauging. Which type of statistics does the engineer see?
A. connectionless-oriented
B. service-oriented
C. connection-oriented
D. application-oriented
Answer: C
Explanation:
Configuration Examples for IP SLAs TCP Connect Operations The following example shows
how to configure a TCP Connection-oriented operation from Device B to the Telnet port (TCP port 23) of IP
Host 1 (IP address 10.0.0.1), as shown in the "TCP Connect Operation" figure in the "Information About
the IP SLAs TCP Connect Operation" section. The operation is scheduled to start immediately. In this
example, the control protocol is disabled on the source (Device B). IP SLAs uses the control protocol to
notify the IP SLAs responder to enable the target port temporarily. This action allows the responder to reply
to the TCP Connect operation. In this example, because the target is not a Cisco device and a well- known
TCP port is used, there is no need to send the control message. Device A (target device) Configuration
configure terminal ip sla responder tcp-connect ipaddress 10.0.0.1 port 23
Reference: http://
www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipsla/configuration/15-mt/sla-15- mt-book/ sla_tcp_conn.html
Q2. Scenario:
You have been asked to evaluate an OSPF network setup in a test lab and to answer questions a customer has about its operation. The customer has disabled your access to the show running-config command.
How many times was SPF algorithm executed on R4 for Area 1?
A. 1
B. 5
C. 9
D. 20
E. 54
F. 224
Answer: C
Explanation:
Q3. Refer to the exhibit. The command is executed while configuring a point-to-multipoint Frame Relay interface. Which type of IPv6 address is portrayed in the exhibit?
A. link-local
B. site-local
C. global
D. multicast
Answer: A
Explanation:
Q4. An engineer has configured a router to use EUI-64, and was asked to document the IPv6 address of the router. The router has the following interface parameters:
mac address C601.420F.0007
subnet 2001:DB8:0:1::/64
Which IPv6 addresses should the engineer add to the documentation?
A. 2001:DB8:0:1:C601:42FF:FE0F:7
B. 2001:DB8:0:1:FFFF:C601:420F:7
C. 2001:DB8:0:1:FE80:C601:420F:7
D. 2001:DB8:0:1:C601:42FE:800F:7
Answer: A
Explanation:
Explanation: Extended Unique Identifier (EUI), as per RFC2373, allows a host to assign iteslf a unique 64-
Bit IP Version 6 interface identifier (EUI-64). This feature is a key benefit over IPv4 as it eliminates the
need of manual configuration or DHCP as in the world of IPv4. The IPv6 EUI-64 format address is obtained
through the 48-bit MAC address. The Mac address is first separated into two 24-bits, with one being OUI
(Organizationally Unique Identifier) and the other being NIC specific. The 16-bit 0xFFFE is then inserted
between these two 24-bits to for the 64-bit EUI address. IEEE has chosen FFFE as a reserved value which
can only appear in EUI-64 generated from the EUI-48 MAC address. Here is an example showing how the
Mac Address is used to generate EUI.
Next, the seventh bit from the left, or the universal/local (U/L) bit, needs to be inverted. This bit identifies
whether this interface identifier is universally or locally administered. If 0, the address is locally
administered and if 1, the address is globally unique. It is worth noticing that in the OUI portion, the globally
unique addresses assigned by the IEEE has always been set to 0 whereas the locally created addresses
has 1 configured. Therefore, when the bit is inverted, it maintains its original scope (global unique address
is still global unique and vice versa). The reason for inverting can be found in RFC4291 section 2.5.1.
Reference: https:// supportforums.cisco.com/document/100566/understanding-ipv6-eui-64-bit- address
Q5. When using SNMPv3 with NoAuthNoPriv, which string is matched for authentication?
A. username
B. password
C. community-string
D. encryption-key
Answer: A
Explanation:
The following security models exist: SNMPv1, SNMPv2, SNMPv3. The following security
levels exits: "noAuthNoPriv" (no authentiation and no encryption noauth keyword in CLI),
"AuthNoPriv" (messages are authenticated but not encrypted auth keyword in CLI), "AuthPriv" (messages
are authenticated and encrypted priv keyword in CLI). SNMPv1 and SNMPv2 models only support the
"noAuthNoPriv" model since they use plain community string to match the incoming packets. The SNMPv3
implementations could be configured to use either of the models on per-group basis (in case if
"noAuthNoPriv" is configured, username serves as a replacement for community string). Reference: http://
blog.ine.com/2008/07/19/snmpv3-tutorial/
Q6. A network engineer executes the show ip flow export command. Which line in the output indicates that the send queue is full and export packets are not being sent?
A. output drops
B. enqueuing for the RP
C. fragmentation failures
D. adjacency issues
Answer: A
Explanation:
Table 5 show ip flow export Field Descriptions Field Description Exporting flows to 10.1.1.1
Specifies the export destinations and ports. (1000) and 10.2.1.1 The ports are in parentheses. Exporting
using source Specifies the source address or interface. IP address 10.3.1.1 Version 5 flow records
Specifies the version of the flow. 11 flows exported in 8 udp The total number of export packets sent, and
datagrams the total number of flows contained within them. 0 flows failed due to lack of No memory was
available to create an export export packet packet. 0 export packets were sent The packet could not be
processed by CEF or up to process level by fast switching, possibly because another feature requires
running on the packet. 0 export packets were Indicates that CEF was unable to switch the dropped due to
no fib packet or forward it up to the process level. 0 export packets were dropped due to adjacency issues
0 export packets were Indicates that the packet was dropped because dropped due to of problems
constructing the IP packet. fragmentation failures 0 export packets were dropped due to encapsulation
fixup failures 0 export packets were Indicates that there was a problem transferring dropped enqueuing for
the the export packet between the RP and the line RP card. 0 export packets were dropped due to IPC
rate limiting 0 export packets were Indicates that the send queue was full while dropped due to output the
packet was being transmitted. drops
Reference: http://www.cisco.com/c/en/us/td/docs/ios/12_0s/feature/guide/oaggnf.html
Q7. Which NetFlow component is applied to an interface and collects information about flows?
A. flow monitor
B. flow exporter
C. flow sampler
D. flow collector
Answer: A
Explanation:
Flow monitors are the NetFlow component that is applied to interfaces to perform network
traffic monitoring. Flow monitors consist of a record and a cache. You add the record to the flow monitor
after you create the flow monitor. The flow monitor cache is automatically created at the time the flow
monitor is applied to the first interface. Flow data is collected from the network traffic during the monitoring
process based on the key and nonkey fields in the record, which is configured for the flow monitor and
stored in the flow monitor cache. Reference: http://www.cisco.com/c/en/us/td/docs/ios/fnetflow/command/
reference/fnf_book/fnf_01.html#w p1314030
Q8. Which two actions must you perform to enable and use window scaling on a router? (Choose two.)
A. Execute the command ip tcp window-size 65536.
B. Set window scaling to be used on the remote host.
C. Execute the command ip tcp queuemax.
D. Set TCP options to "enabled" on the remote host.
E. Execute the command ip tcp adjust-mss.
Answer: A,B
Explanation:
The TCP Window Scaling feature adds support for the Window Scaling option in RFC 1323,
TCP Extensions for High Performance . A larger window size is recommended to improve TCP performance in network paths with large bandwidth-delay product characteristics that are called Long Fat
Networks (LFNs).
The TCP Window Scaling enhancement provides that support. The window scaling extension in Cisco IOS software expands the definition of the TCP window to 32 bits and then uses a scale factor to carry this 32-bit value in the 16-bit window field of the TCP header.
The window size can increase to a scale factor of 14. Typical applications use a scale factor of 3 when deployed in LFNs.
The TCP Window Scaling feature complies with RFC 1323. The larger scalable window size will allow TCP to perform better over LFNs.
Use the ip tcp window-size command in global configuration mode to configure the TCP window size. In order for this to work, the remote host must also support this feature and its window size must be increased.
Reference: http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipapp/
configuration/12-4t/iap-12- 4t-book/iap-tcp.html#GUID-BD998AC6-F128-47DD-B5F7-B226546D4B08
Q9. Router A and Router B are configured with IPv6 addressing and basic routing capabilities using OSPFv3. The networks that are advertised from Router A do not show up in Router B's routing table. After debugging IPv6 packets, the message "not a router" is found in the output. Why is the routing information not being learned by Router B?
A. OSPFv3 timers were adjusted for fast convergence.
B. The networks were not advertised properly under the OSPFv3 process.
C. An IPv6 traffic filter is blocking the networks from being learned via the Router B interface that is connected to Router A.
D. IPv6 unicast routing is not enabled on Router A or Router B.
Answer: D
Explanation:
show ipv6 traffic Field Descriptions
Field Description
source- Number of source-routed packets.
routed
truncated Number of truncated packets.
format Errors that can result from checks performed on header fields, errors the version number, and
packet length.
not a Message sent when IPv6 unicast routing is not enabled.
router
Reference:
http://www.cisco.com/c/en/us/td/docs/ios/ipv6/command/reference/ipv6_book/ipv6_16.html
Q10. Which technology was originally developed for routers to handle fragmentation in the path between end points?
A. PMTUD
B. MSS
C. windowing
D. TCP
E. global synchronization
Answer: A
Explanation: