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Taking the test in two weeks, would like to have a good dump to continuing with studying if possible. Thanks so much. any help apprectiated
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Question 1.
Which of the following types of portable media offers the LARGEST storage capacity?
A. DVD.DL
B. CD.RW
C. CD.R
D. DVD.R
Answer: A
Question 2.
Which of the following are valid ports for printing over a network? (Select TWO).
A. USB 001
B. \\computername\sharename
C. SNMP
D. IP_ip_address
E. IEEE 1394
Answer: B, D
Explanation:
\\computername\sharename is a net command that manages network print jobs and IP_ip_address is a static IP address that is configured on a network printer so that it can be seen on the network by a computer. This address can be verified from printer's configuration.
Question 3.
While performing a preventative maintenance check on a personal computer, a technician notices that several unused expansion card slots have open ports.
Which of the following BEST describes why the covers for these card slots should be reinstalled?
A. Help limit radio frequency interference (RFI) inside the case.
B. Help ensure proper air flow through the case.
C. Help prevent moisture buildup in the case.
D. Help limit electrostatic discharge (ESD) inside the case.
Answer: B
Explanation:
The chassis of a PC is designed for proper internal airflow across the various components. However, if your PC's enclosures are open, then the cooling of the PC changes dramatically. The cooling of some components can be reduced or totally eliminated and can cause damage.
Question 4.
Which of the following protocols uses port 80?
A. SMTP
B. HTTP
C. HTTPS
D. FTP
Answer: B
Explanation:
The port 80 is associated with HTTP TCP/IP protocol.
Question 5.
Which of the following allows verification of the port that a printer is currently using?
A. The print queue window from system tray
B. Properties of the printer from the Printers Control Panel
C. Print spooler view in the Printers Control Panel
D. Properties of the port within Device Manager
Answer: B
Explanation:
To find the port that your printer is currently using, you need to open the properties of the printer from the Printer's Control Panel
Question 6.
Users are reporting that print jobs being sent to a shared printer are not printing. A technician has verified the printer is online and prints a configuration page from the printer.
Which of the following is the MOST likely cause of the issue? (Select TWO).
A. QoS for printing is not functioning over the LAN.
B. The printer needs to have a cartridge replaced.
C. A job in error status is at the top of the print queue.
D. The printers IP address has changed.
E. New drivers have been released and need to be installed.
Answer: C, D
Explanation:
The possible cause of the problem in this case is that either a job in error status is at the top of the print queue or the IP address of the printer has changed. Sometimes, certain print codes in the file that is printing can confuse the print job and the job gets stuck in the print queue. The printer would not start printing again till that print job is removed from the queue. Sometime if the IP address of the printer is changed you cannot print. To find this problem you can ping the printer from your computer.
Question 7.
Which of the following connector types is used with twisted pair cable?
A. T-Connector
B. BNC
C. RJ-45
D. LC
Answer: C
Explanation:
With twisted pair cable you can use RJ-45 connector. The UTP ( unshilded twisted pair) cable often is installed using a Registered Jack 45 (RJ-45) connector. The RJ-45 is an eight-wire connector used commonly to connect computers onto a local-area network (LAN), especially Ethernets
Question 8.
Which of the following bus speeds is used for a PCIe card? (Select TWO).
A. 1x
B. 3x
C. 6x
D. 8x
E. 24x
Answer: A, D
Explanation:
For a PCIe or PCI expansion card, 1x and 8x bus speeds can be used.
Question 9.
A user calls and says they cannot get to the Internet. How would a technician walk the user through checking the IP address and default Gateway on the computer?
A. Start>Run>typeipconfig>click OK and ask user to read the results.
B. Start>Run>typecmd>click OK>type ipconfig /flushdns>press enter and ask user to read the
results.
C. Start>Run>typecmd>click OK>type ipconfig /release>press enter key and ask user to read the
results.
D. Start>Run>typecmd>click OK>type ipconfig /all>press enter key and ask user to read the
results.
Answer: D
Explanation:
The Ipconfig command is used to find the IP configuration information of a computer. The Syntax IPCONFIG /all displays full configuration information. You can type the Ipconfig command by clicking Start->Run and then typing cmd to open the command prompt to type the ipconfig command.
Question 10.
Which of the following BEST describes the function of a DNS server?
A. Secures network traffic through shared key encryption.
B. Provides resolution of host names to IP addresses.
C. Provides security for a network through the use of ACLs.
D. Dynamically assigns IP addresses for easy client configuration.
Answer: B
Explanation:
The main function of DNS is the mapping of IP addresses to human readable names. The DNS server strictly functions as an ip address lookup for a given domain name.
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Question 1.
Exhibit:
The network has two gatekeepers that control four zones. Which command is used to ensure that the aggregate bandwidth between zones that are controlled by the Portland Gatekeeper and the Seattle Gatekeeper is limited to 100,000 kbps?
A. bandwidth interzone 166667
B. bandwidth remote 166667
C. bandwidth session 166667
D. bandwidth region 166667
E. bandwidth zone 166667
Answer: B
Question 2.
ITCertKeys.com has a single Cisco IPVC 3511 MCU E. At present there are two conferences occurring as follows:
Conference 1:three conference participantstransrating 768 kbps to 384 kbpsenhanced continuous presence
Conference 2:three conference participantstransrating 768 kbps to 384 kbpsmultiple
conference view (3)A third conference is desired with the following requirements:
Conference 3:three conference participants
What will occur when the third conference is attempted?
A. The third conference will succeed as desired.
B. The third conference will succeed, but without the enhanced continuous presence.
C. The third conference will fail because an IPVC 3511 MCU does not have the resources for
three conferences of three people each.
D. The third conference will fail because the EMP module does not have the resources to provide
the number of required services.
Answer: A
Question 3.
Exhibit:
ITCertKeys.com is using Cisco meeting place at its world headquarters; ITCertKeys.com also has a Cisco CallManager cluster. The Cisco CallManager cluster includes a video deployment with both SCCP and H.323 video endpoints. The videoconferencing capability is provided by a Cisco IPVC 3540 Series Videoconferencing System.
Using the topology in the exhibit, what should be the video gateway location?
A. A
B. B
C. C
D. D
Answer: B
Question 4.
ITCertKeys.com is deploying Cisco VT Advantage to enable executives to participate in video calls with customers and suppliers.
Which two devices can be used to allow these external calls to be placed over a dedicated PRI? (Choose two.)
A. Cisco IPVC 3521
B. Cisco IPVC 3526
C. Cisco IPVC 3540
D. Cisco Multiservice IP-to-IP Gateway
E. Cisc MCM proxy
Answer: B, C
Question 5.
Exhibit:
A network has two gatekeepers that control four zones.
Which command is used to ensure that the aggregate bandwidth between the Seattle and Spokane zones is limited to 100,000 kbps?
A. bandwidth interzone 166667
B. bandwidth remote 166667
C. bandwidth session 166667
D. bandwidth region 166667
E. bandwidth zone 166667
Answer: A
Question 6.
Exhibit:
CAC is being configured for the centralized call-processing video telephony network. Each video terminal is capable of a maximum data rate of 320 kbps, and two video terminals are planned for each site. The requirement is to make two simultaneous video calls between the ITCertKeys main office and each remote ITCertKeys branch office site. The audio codec will be G.711.
In order to ensure quality of service for calls, which action should be taken when configuring Cisco CallManager?
A. Set the location video call bandwidth between the central site and each remote site to 922
kbps.
B. Set the location video call bandwidth between the central site and each remote site to 384
kbps.
C. Set the location video call bandwidth between the central site and each remote site to 768
kbps.
D. Configure the gatekeeper to set the req-qos guaranteed-delay video bandwidth at 922 kbps
between the central site and each remote site.
E. Configure the gatekeeper to set the req-qos guaranteed-delay video bandwidth at 384 kbps
between the central site and each remote site.
F. Configure the gatekeeper to set the req-qos guaranteed-delay video bandwidth at 768 kbps
between the central site and each remote site.
Answer: C
Question 7.
ITCertKeys.com has a requirement for up to 10 simultaneous conferences of four people each, and each conference requires 384-kbps to 128-kbps transrating and H.261 to H.263 video transcoding.
What should this company purchase?
A. one Cisco IPVC 3540 Transcoder Module for MC06A
B. one Cisco IPVC 3540 Transcoder Module for MC06A with an EMP blade
C. one Cisco IPVC 3540 Transcoder Module for MC06A with an EMP3 blade
D. two Cisco IPVC 3540 Transcoder Modules for MC06A
E. two Cisco IPVC 3540 Transcoder Modules for MC06A, each with an EMP blade
F. two Cisco IPVC 3540 Transcoder Modules for MC06A, each with an EMP3 blade
Answer: C
Question 8.
Which three factors must be considered when designing a H.323 videoconferencing dial plan? (Choose three.)
A. the number of sites in the enterprise
B. the number and location of gatekeepers
C. the incoming PSTN call routing method
D. the DNs and location of conferencing MCUs to be deployed
E. the videoconferencing features and applications to be deployed
F. the location of voice gateways
Answer: A, C, D
Question 9.
Exhibit:
The network has two gatekeepers that control four zones. Which command is used to ensure that no single call in Zone Eugene uses more than 768 kbps?
A. bandwidth interzone 768
B. bandwidth limit 768
C. bandwidth session 768
D. bandwidth call 768
E. bandwidth zone 768
Answer: C
Question 10.
What is traditionally used in a H.323 gatekeeper to pool endpoints into groups?
A. zones
B. clusters
C. calling search spaces
D. toll bypass routing
Answer: A
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Question 1.
When configuring the Cisco VPN Client with transparent tunneling, what is true about the IPSec over TCP option?
A. The port number is negotiated automatically.
B. Clients will have access to the secured tunnel and local resources.
C. The port number must match the configuration on the secure gateway.
D. Packets are encapsulated using Protocol 50 (Encapsulating Security Payload, or ESP).
Answer: C
Question 2.
Refer to the exhibit.
MPLS must be enabled on all routers in the MPLS domain that consists of Cisco routers and equipment of other vendors.
What MPLS distribution protocol(s) should be used on router R2 Fast Ethernet interface Fa0/0 so that the Label Information Base (LIB) table is populated across the MPLS domain?
A. Only LDP should be enabled on Fa0/0 interface.
B. Only TDP should be enabled on Fa0/0 interface.
C. Both distribution protocols LDP and TDP should be enabled on the Fa0/0 interface.
D. MPLS cannot be enabled in a domain consisting of Cisco and non-Cisco devices.
Answer: C
Question 3.
Which two statements about common network attacks are true? (Choose two.)
A. Access attacks can consist of password attacks, trust exploitation, port redirection, and man in-
the- middle attacks.
B. Access attacks can consist of password attacks, ping sweeps, port scans, and man-in-the-
middle attacks.
C. Access attacks can consist of packet sniffers, ping sweeps, port scans, and man-in-the- middle
attacks.
D. Reconnaissance attacks can consist of password attacks, trust exploitation, port redirection
and Internet information queries.
E. Reconnaissance attacks can consist of packet sniffers, port scans, ping sweeps, and Internet
information queries.
F. Reconnaissance attacks can consist of ping sweeps, port scans, man-in-middle attacks and
Internet information queries.
Answer: A, E
Question 4.
Which two statements about worms, viruses, or Trojan horses are true? (Choose two.)
A. A Trojan horse has three components: an enabling vulnerability, a propagation mechanism,
and a payload.
B. A Trojan horse virus propagates itself by infecting other programs on the same computer.
C. A virus cannot spread to a new computer without human assistance.
D. A virus has three components: an enabling vulnerability, a propagation mechanism, and a
payload.
E. A worm can spread itself automatically from one computer to the next over an unprotected
network.
F. A worm is a program that appears desirable but actually contains something harmful.
Answer: C, E
Question 5.
Which two statements about management protocols are true? (Choose two.)
A. Syslog version 2 or above should be used because it provides encryption of the syslog
messages.
B. NTP version 3 or above should be used because these versions support a cryptographic
authentication mechanism between peers.
C. SNMP version 3 is recommended since it provides authentication and encryption services for
management packets.
D. SSH, SSL and Telnet are recommended protocols to remotely manage infrastructure devices.
E. TFTP authentication (username and password) is sent in an encrypted format, and no
additional encryption is required.
Answer: B, C
Question 6.
Which two statements about the Cisco Autosecure feature are true? (Choose two.)
A. All passwords entered during the Autosecure configuration must be a minimum of 8 characters
in length.
B. Cisco 123 would be a valid password for both the enable password and the enable secret
commands.
C. The auto secure command can be used to secure the router login as well as the NTP and SSH
protocols.
D. For an interactive full session of AutoSecure, the auto secure login command should be used.
E. If the SSH server was configured, the 1024 bit RSA keys are generated after the auto secure
command is enabled.
Answer: C, E
Question 7.
Which three statements are correct about MPLS-based VPNs? (Choose three.)
A. Route Targets (RTs) are attributes attached to a VPNv4 BGP route to indicate its VPN
membership.
B. Scalability becomes challenging for a very large, fully meshed deployment.
C. Authentication is done using a digital certificate or pre-shared key.
D. A VPN client is required for client-iniated deployments.
E. A VPN client is not required for users to interact with the network.
F- An MPLS-based VPN is highly scalable because no site-to-site peering is required.
Answer: A, E, F
Question 8.
Which IPsec mode will encrypt a GRE tunnel to provide multiprotocol support and reduced overhead?
A. 3DES
B. multipoint GRE
C. tunnel
D. transport
Answer: D
Question 9.
Which two statements are true about broadband cable (HFC) systems? (Choose two.)
A. Cable modems only operate at Layer 1 of the OSI model.
B. Cable modems operate at Layers 1 and 2 of the OSI model.
C. Cable modems operate at Layers 1, 2, and 3 of the OSI model.
D. A function of the cable modem termination system (CMTS) is to convert the modulated signal
from the cable modem into a digital signal.
F. A function of the cable modem termination system is to convert the digital data stream from the
end user host into a modulated RF signal for transmission onto the cable system.
Answer: B, D
Question 10.
Refer to the exhibit.
Which two statements about the AAA configuration are true? (Choose two.)
A. A good security practice is to have the none parameter configured as the final method used to
ensure that no other authentication method will be used.
B. If a TACACS+ server is not available, then a user connecting via the console port would not be
able to gain access since no other authentication method has been defined.
C. If a TACACS+ server is not available. then the user Bob could be able to enter privileged
mode as long as the proper enable password is entered.
D. The aaa new-model command forces the router to override every other authentication method
previously configured for the router lines.
E. To increase security, group radius should be used instead of group tacacs+.
F. Two authentication options are prescribed by the displayed aaa authentication command.
Answer: D, F
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Question 1. ITCertKeys.com wants to use distinct security policies for different departments. What must be configured? A. individual security level for each department B. separate ACL group for each department C. distinct VLAN for each department D. unique firewall context for each department Answer: D Question 2. Exhibit: You work as a network administrator at ITCertKeys.com. You study the exhibit carefully. ITCertKeysA, ITCertKeysB, C, and ITCertKeys4 each represents a model for placement of a default gateway. Which model allows the maximum number of application and security services? A. model ITCertKeysB B. model C C. model ITCertKeysA D. model ITCertKeysD Answer: B Question 3. Which of the following attack types should be mitigated in the data center core layer? A. IP spoofing B. MAC address spoofing C. port scans D. DDoS attacks Answer: D Question 4. Exhibit: You work as a network administrator at ITCertKeys.com. You study the exhibit carefully. A failure occurs on one of the access layer uplinks. Which Layer 2 topology can cause a break in connectivity between the FWSMs? A. looped triangle B. loop-free inverted U C. loop-free U D. looped square Answer: C Question 5. Which type of HPC application requires low latency? A. financial analytics B. seismic and geophysical modeling C. digital image rendering D. finite element analysis Answer: D Question 6. Which statement best describes the data center core layer? A. provides a resilient Layer 2 routed fabric B. load balances traffic between the core and aggregation layers C. is typically merged with the campus core layer D. connects to the campus aggregation layer Answer: B Question 7. Which data center network-architecture change is a result of the adoption of blade and 1-RU server technologies? A. Layer 3 fault domains growing smaller B. Layer 2 fault domains growing larger C. Layer 2 fault domains growing smaller D. Layer 3 fault domains growing larger Answer: B Question 8. What advantage does InfiniBand have over Gigabit Ethernet in HPC environments? A. simpler cabling B. longer distance support C. more sophisticated traffic management D. lower latency Answer: D Question 9. Exhibit: You work as a network administrator at ITCertKeys.com. You study the exhibit carefully. Where is Layer 2 adjacency required? A. server-to-server only B. aggregation-to-access only C. aggregation-to-access and access-to-server D. access-to-server only Answer: D Question 10. According to the Cisco Network Foundation Protection model, which security feature is recommended for the data center core layer? A. prefix filtering B. Dynamic ARP Inspection C. traffic rate limiting D. control plane protection Answer: D
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Question 1.
ITCertKeys.com is a semiconductor discrete manufacturing organization. It has its own manufacturing and distribution centers located globally.
It has these operating Units:
US - USA operating unit
CAN - Canadian operating unit
UK - UK operating unit
MX - Mexican operating unit
IND - India operating unit
SPA - Spain operating unit
FRA - France operating unit
NL - Netherlands operating Unit
GER - Germany operating unit.
These are the inventory organizations that exist in each operating unit:
Inventory Org - Operating unit
--------------------------------------------
CK (Master Org) - US
US1 (Child Org) - US
US2 (Child Org) - US
CA1 (Child Org) - CAN
MX1 (Child Org) - MX
IN1 (Child Org) - IND
SP1 (Child Org) - SPA
FR1 (Child Org) - FRA
NL1 (Child Org) - NL
GE1 (Child Org) - GER
Which three statements are true? (Choose three.)
A. Master organization CK cannot be shared across operating units.
B. All inventory organizations do not need to be in the same operating unit to assign items.
C. Items defined in CK organization can be assigned to US1,US2, NL1 and MX1 inventory
organizations.
D. Organization items in the inventory responsibility assigned to FRA operating unit can be
restricted, to not view the organization items assigned to US2 inventory organization.
E. You can define an item in IN1 inventory organization and assign it to GE1 inventory
organization.
F. Items cannot be assigned to inventory organizations across operating units.
Answer: B, C, D
Question 2.
You specified cycle count measurement error values when you defined your item at the master item or organization item level. You also specified a cycle count quantity variance approval tolerance at the cycle count item level. If the actual cycle count quantity for your item differs from the system on-hand quantity by less than the specified measurement error, Oracle Inventory _____.(Select one answer)
A. does not consider cycle count approval tolerance but makes a cycle count adjustment
B. applies the measurement error to the cycle count approval tolerance before the approval
decision and makes a cycle count adjustment when approved
C. does not consider cycle count approval tolerance and does not make a cycle count adjustment
D. applies the measurement error to the cycle count approval tolerance before the approval
decision and does not make a cycle count adjustment when approved
Answer: B
Question 3.
Which three statements are true about defining an item using a template? (Assume that there are no Interdependent Attributes.) (Choose three.)
A. A template can be applied only at the master organization level.
B. A template applied to a master item, which has already been assigned to a child organization,
can still update the organization-controlled item.
C. Modifying an item template will automatically update the items that were previously defined
using that template.
D. A template can be applied at the master or child organization levels.
E. You can apply multiple templates to an item.
F. Template application is additive. If you apply a second template to an item, the item will retain
the values of all the attributes that were not enabled by the second template.
G. Template application is exclusive. If you apply a second template to an item, the item will not
retain any values of the prior template.
Answer: D, E, F
Question 4.
You are setting up a requisition move order for which approval is required. At the organization level, you have defined the following:
However, the approval process is not being enabled for the organization item.
What is a possible reason?
A. The subinventory source type has not been set to pull level.
B. The Move Order Timeout Action has been set to a value greater than zero.
C. A planner has not been assigned to the organization item.
D. The Move Order Timeout Period has been set to a value greater than zero.
Answer: C
Question 5.
From which Oracle applications can 'in-transit' receipts be received into an organization?
A. Purchasing and Work in Process
B. Purchasing and Order Management
C. Purchasing
D. Purchasing, Inventory, and Work in Process
Answer: C
Question 6.
A customer who distributes widgets has a warehouse with locations where material is stored. In the customer's current system, users may receive material on a purchase order and indicate the location where it should go, but when the material is physically sent to the location, they may discover that the location is full.
What is the best way to solve the problem?
A. Set up the locations as locators, and use the capacity tab of the locator definition form to enter
the maximum number of items that can be stored in the locator.
B. Set up each location as a subinventory and select the nettable flag.
C. Set up each location as a subinventory and select the Allow Reservation flag.
D. Set up each location as an organization and create locators in the organization.
Answer: A
Question 7.
You specified cycle count measurement error values when you defined your item at the master item or organization item level. You also specified a cycle count quantity variance approval tolerance at the cycle count item level. If the actual cycle count quantity for your item differs from the system on-hand quantity by less than the specified measurement error, Oracle Inventory _____.(Select one answer)
A. does not consider cycle count approval tolerance but makes a cycle count adjustment
B. applies the measurement error to the cycle count approval tolerance before the approval
decision and makes a cycle count adjustment when approved
C. applies the measurement error to the cycle count approval tolerance before the approval
decision and does not make a cycle count adjustment when approved
D. does not consider cycle count approval tolerance and does not make a cycle count adjustment
Answer: B
Question 8.
Which three are Oracle Inventory replenishment methods? (Choose three.)
A. MRP (Materials Requirement Planning)
B. Replenishment Counting
C. Safety Stock
D. Kanban
E. Min-max Planning
Answer: B, D, E
Question 9.
You are defining the staging subinventory for your sales order pick release rule.
Which flag should be set on the subinventory setup for pick release to work?
A. The subinventory should have the Nettable flag selected.
B. The subinventory should have the Depreciable flag selected.
C. The subinventory should have the Reservable flag selected.
D. The subinventory should have the Pre-Processing Lead Time field populated.
Answer: C
Question 10.
ITCertKeys.com has portable bar code readers that are used to scan and read data about the amount of time charged on a resource that has been utilized on the manufacturing floor. This data about utilization is then processed in the Oracle Work in Process module by using a _____.
A. Material Transaction Manager
B. Cost Manager
C. Lot Move Transaction Manager
D. Concurrent Manager
E. Move Transaction Manager
Answer: C
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Question 1.
Which of the following markers can be set by Committed Access Rate (CAR)? (Choose all that apply.)
A. DSCP bits
B. QoS Group
C. ATM CLP bit
D. Frame Relay DE bit
E. IP precedence bits
Answer: A, B, E
Explanation:
Source: Cisco IP QoS Introduction, Page 64
Question 2.
What makes the DiffServ model more scalable than the IntServ model? (Choose all that apply.)
A. DiffServ makes use of per-aggregate QoS instead of per-flow QoS.
B. DiffServ makes use of hop-by-hop signaling which allows DiffServ to scale to a larger number
of application flows.
C. DiffServ is capable of implementing admission control either locally on the routers or be
offloaded to a central policy server using the COPS protocol.
D. DiffServ routers are not compelled to track the state information for each individual flow.
Answer: A, D
Incorrect:
B. No hop-by-hop signaling uses per-hop behavior
C. This is a feature of both models Sources: Cisco IP QoS Introduction
http://www.cisco.com/en/US/tech/ ITK5 43/ ITK7 66/technologies_white_paper09186a00800a3e2f.shtml
Question 3.
The newly appointed ITCertKeys trainee technician wants to know what the benefits of
using traffic shaping to implement network rate limiting is.What will your reply be?
(Choose all that apply.)
A. Traffic shaping is an effective tool for rate-limiting VoIP traffic.
B. It will not increase packet loss.
C. It will not add to packet transit delays.
D. Traffic shaping can interact with congestion mechanisms embedded in Frame Relay.
E. Traffic shaping can be used on inbound and outbound traffic on a router.
Answer: B, D
Incorrect:
A. Shaping adds variable delay to traffic, possibly causing jitter
C. A shaper typically delays excess traffic using a buffer
E. This is a feature of policing
Explanation:
Source: Cisco IP QoS Traffic Shaping and Policing
Question 4.
Study the Exhibit below carefully:
Router# show interfaces hssi 0/0/0 rate-limit
Hssi0/0/0 45Mbps to R1
Input
matches: all traffic
params: 20000000 bps, 24000 limit, 24000 extended limit
conformed 8 packets, 428 bytes; action: transmit
exceed 0 packets, 0 bytes; action: drop
last packet: 8680ms ago, current burst: 0 bytes
last cleared 00:03:59 ago, conformed 0 bps, exceed 0 bps
Output
matches: all traffic
params: 20000000 bps, 24000 limit, 24000 extended limit
conformed 0 packets, 0 bytes; action: transmit
exceed 0 packets, 0 bytes; action; drop
last packet: 8680ms ago, current burst: 0 bytes
last cleared 00:03:59 ago, conformed 0 bps, exceed 0 bps
According to the exhibit, the router has been configured with Committed Access Rate (CAR) to rate limit traffic.
What data rate has the traffic been limited to?
A. 192 Kbps
B. 2400 Kbps
C. 4,5 Mbps
D. 20 Mbps
E. 40 Mbps
Answer: D
Explanation:
In the configuration example, CAR is applied on the input and output of a customer interface on the provider edge router. Traffic is policed to 256 Kbps on input and output, with some bursting allowed. All exceeding traffic is dropped at the provider edge. The result of the configuration is that traffic to and from the customer is limited to the average rate of approximately 256kbps (256000 in the configuration) with sustained bursts of approximately 32kbps (4kBps or 4000 in the configuration). Initial bursts at line speed can last up to 3 seconds because the token bucket can hold up to 96000 tokens (bytes) which equals 768000 bits (3 x 256000 bits).
Source: Cisco IP QoS Traffic Shaping and Policing, Page 4-91
Question 5:
The newly appointed ITCertKeys trainee technician wants to know which type of software queuing mechanism is Frame Relay Traffic Shaping implemented with on the physical interface.
What will your reply be?
A. Priority Queuing (PQ)
B. Custom Queuing (CQ)
C. FIFO
D. Weighted Fair Queuing (WFQ)
E. IP Real Time Transport Protocol (RTP) Priority
Answer: D
Explanation:
Works on any (sub) interface type
Shapes traffic on that (sub)interface basis
Can use any physical interface queuing (FIFO, PQ, CQ or WFQ)
Only uses WFQ as the shaping queue (that is, on the input of the shaper)
In contrast, Frame Relay Traffic Shaping:
Works only on Frame Relay (sub) interfaces
Shapes traffic inside individual FR Virtual Circuits
Only permits WFQ as the physical interface queuing method
Can use any queuing method as the shaping queue (that is, on the input of the shaper)
Source: Cisco IP QoS Traffic Shaping and Policing, Page 4-47
Question 6.
Why is it beneficial to make use of Enhanced LMI (ELMI) on Cisco networks?
A. ELMI is responsible for providing virtual provisioning tools at the edge of the Frame Relay
network.
B. ELMI permits routers to dynamically download QoS information from Cisco switches for use in
traffic shaping or for congestion management purposes.
C. ELMI provides the router the ability to use additional QoS tools including rate limiting with CAR
and the Modular QoS Command Line Interface (MQC).
D. ELMI allows the router to deliver packets at the line rate of the Frame Relay interface,
regardless of the condition of the Frame Relay network.
Answer: B
Explanation:
Source: Cisco IP QoS Traffic Shaping and Policing, Page 4-58
Question 7.
Which of the following statements are true when you compare DSCP and IP Precedence to each other? (Choose all that apply.)
A. DSCP is backwards compatible with IP Precedence.
B. DSCP cannot be easily mapped into QoS because of its expanded classification options.
C. DSCP is more granular the IP Precedence, since more marking combinations are available.
D. DSCP appears stubby when compared IP Precedence, since devices make use of DSCP as
defined in RFC exclusively.
E. DSCP is 6 bits long and IP Precedence is 3 bits long.
F. DSCP is more restrictive than IP Precedence, since devices are only allowed to use DSCP as
defined in RFCs.
Answer: A, C, E
Explanation:
A)DSCP is backward compatible with IP Precedence (Class Selector Code point, RFC 1812) but not with the ToS byte definition from RFC 791 ("DTR" bits) Reference: Introduction to IP QoS (Course) p.45
Question 8.
Which MQC command would you use to perform marking properly?
A. precedence 5
B. ip precedence 5
C. set ip precedence 5
D. set ip mark precedence 5
E. mark ip precedence 5
Answer: C
Explanation:
IP precedence is encoded into the three high-order bits of the ToS field in the IP header. It supports eight classes of which two are reserved and should not be used for user-defined classes (IP precedence 6 and 7). IP precedence 0 is the default value and is usually used for the best-effort class. The set ip precedence command marks packets of a class with the specified precedence value.
Reference:
Introduction to IP QoS (Course) p.9-104
Question 9.
Which of the following statements aptly describes a network well designed for QoS?
A. Packets are classified at each router, based on as many detail as possible, typically using
extended IP ACLs to match the packets for classification.
B. Packets are classified at each router, based on socket address only, typically using extended
IP ACLs to match the packets for classification.
C. Packets are classified and marked, close to the edge of the network. The packets are treated
differently based on this marking at the routers in the middle of the network.
D. Packets are classified based on different parameters, but close to the edge of the network.
The packets are automatically characterized based on flow at the routers.
E. Packets are classified based on socket address, at the router closest to the source of the
traffic. The packets are automatically characterized based on flow at the routers.
Answer: C
Explanation:
To achieve the same level of quality in both directions the packets going to and coming from the customer network must first be classified and marked.
Classification and marking packets going to the customer network is a more difficult task because:
1) Classifying and marking must be performed on all edge routers.
2) Classifying and marking requires the identification of the customer network. Using PBR, CAR, CB-Policing or CB-Marking does not scale because it involves the use of access lists (this is especially difficult if customer networks are dynamically learned via BGP).
Reference:
Introduction to IP QoS (Course) p.2-35
Question 10.
The newly appointed ITCertKeys trainee technician wants to know which bit in the ATM header can be marked by the Class Based Marker to extend IP QoS policy into an ATM network.
What will your reply be?
A. DE
B. PTI
C. FECN
D. CLP
E. BECN
Answer: D
Explanation:
The ATM CLP Setting feature somewhat allows users to extend their IP QoS policies into an ATM network by setting the ATM CLP bit in ATM cells based on the IP Precedence value of the packets being sent. As congestion occurs in the ATM network, cells with the CLP bit set are more likely to be dropped, resulting in improved network performance for high priority traffic and applications. The set atm-clp command marks packets of a class with the ATM CLP bit as a part of an input or output policy.
Source: Cisco IP QoS Modular QoS CLI Service Policy, Page 9-110
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Question 1.
A few small ITCertKeys locations use HFC cable to connect to the ITCertKeys WAN.
Which HFC cable network statement is true about the downstream data channel to the customer and the upstream data channel to the service provider?
A. The upstream data path is assigned a channel in a higher frequency range than the
downstream path has.
B. The downstream data path is assigned a 30 MHz channel and the upstream data path is
assigned a 1 MHz channel.
C. The downstream data path is assigned a fixed bandwidth channel and the upstream data path
uses a variable bandwidth channel.
D. Both upstream and downstream data paths are assigned in 6 MHz channels.
E. None of the above.
Answer: D
Explanation:
Hybrid fiber-coaxial (HFC): A mixed optical-coaxial network in which optical fiber replaces some or all of the traditional trunk portion of the cable network. The HFC architecture is the evolution of an initial cable system and signifies a network that incorporates both optical fiber along with coaxial cable to create a broadband network. By upgrading a cable plant to an HFC architecture, you can deploy a data network over an HFC system to offer high-speed Internet services and you can serve more subscribers. The cable network is segmented into smaller service areas in which fewer amplifiers are cascaded after each optical node-typically five or fewer. The tree-and-branch network architecture for HFC can be a fiber backbone, cable area network, superdistribution, fiber to the feeder, or a ring.
Downstream: An RF signal transmission (TV channels, data) from source (headend) to the destination (subscribers). Downstream is also called a forward path.
Upstream: An RF signal transmission opposite to downstream-from subscribers to the headend. Upstream is also called a return or reverse path.
Delivering services over a cable network requires different RF frequencies-the outgoing frequencies are in the 50-to-860 MHz range, the incoming are in the 5-to-42 MHz range. To deliver data services over a cable network TV channels which usually operate at 6 MHz range for the downstream, and 6 MHz or less (for asymmetric cable connections) for upstream traffic from the corresponding frequency range are usually used.
Question 2.
Many small ITCertKeys branch offices use broadband cable for data connection access.
Which three modulation signaling standards are used in broadband cable technology? (Select three)
A. S-Video
B. NTSC
C. SECAM
D. PAL
E. FEC
F. FDM
G. MLP
Answer: B, C, D
Explanation:
Broadband: Data transmission where multiple pieces of data are sent simultaneously to increase the effective rate of transmission. In cable systems, the term broadband refers to the frequency-division multiplexing (FDM) of many signals in a wide radio frequency (RF) bandwidth over an HFC network, and the capability to handle vast amounts of information. NTSC is a North American TV technical standard for analog TV systems. The standard was created in 1941 and is named after the National Television System Committee formed in 1940. The standard uses a 6-MHz modulated signal. PAL is a color encoding system used in broadcast television systems in most of Europe, Asia, Africa, Australia, Brazil, and Argentina, and uses a 6-MHz, 7-MHz, or 8-MHz modulated signal. The color difference signals an alternate phase at the horizontal line rate. SECAM is an analog color TV system used in France and certain Eastern European countries that uses an 8-MHz modulated signal.
Question 3.
Some of the smaller ITCertKeys locations use HFC cable to connect to the ITCertKeys WAN.
Which two statements are true about broadband cable (HFC) systems? (Select two)
A. Cable modems operate at Layers 1, 2, and 3 of the OSI model.
B. Cable modems operate at Layers 1 and 2 of the OSI model.
C. A function of the cable modem termination system is to convert the digital data stream from the
end user host into a modulated RF signal for transmission onto the cable system.
D. Cable modems only operate at Layer 1 of the OSI model.
E. A function of the cable modem termination system (CMTS) is to convert the modulated signal
from the cable modem into a digital signal.
Answer: B, E
Explanation:
Hybrid fiber-coaxial (HFC): A mixed optical-coaxial network in which optical fiber replaces some or all of the traditional trunk portion of the cable network. The HFC architecture is the evolution of an initial cable system and signifies a network that incorporates both optical fiber along with coaxial cable to create a broadband network. By upgrading a cable plant to an HFC architecture, you can deploy a data network over an HFC system to offer high-speed Internet services and you can serve more subscribers. The cable network is segmented into smaller service areas in which fewer amplifiers are cascaded after each optical node-typically five or fewer. The tree-and-branch network architecture for HFC can be a fiber backbone, cable area network, superdistribution, fiber to the feeder, or a ring.
Question 4.
A ITCertKeys remote user is getting Internet access from the local cable provider.
When an individual is connected to the Internet by way of a CATV cable service, what kind of traffic is considered upstream traffic?
A. Traffic going from the user's home traveling to the headend.
B. Broadcast traffic, including the cable TV signals.
C. Traffic between the headend and the TV signal.
D. Traffic between the headend and the supplier antenna.
E. Traffic from outside the local cable segment serving the user's home.
F. All of the above can be considered upstream
Answer: A
Explanation:
In the CATV space, the downstream channels in a cable plant (cable head-end to subscribers) is a point-to-multipoint channel. This does have very similar characteristics to transmitting over an Ethernet segment where one transmitter is being listened to by many receivers. The major difference is that base-band modulation has been replaced by a more densely modulated RF carrier with very sophisticated adaptive signal processing and forward error correction (FEC). In the upstream direction (subscriber cable modems transmitting towards the head-end) the environment is many transmitters and one receiver. This introduces the need for precise scheduling of packet transmissions to achieve high utilization and precise power control so as to not overdrive the receiver or other amplifier electronics in the cable system. Since the upstream direction is like a single receiver with many antennas, the channels are much more susceptible to interfering noise products. In the cable industry, we generally call this ingress noise. As ingress noise is an inherent part of CATV plants, the observable impact is an unfortunate rise in the average noise floor in the upstream channel. To overcome this noise jungle, upstream modulation is not as dense as in the downstream and we have to use more effective FEC as used in the downstream.
Reference:
http://www.cisco.com/warp/public/759/ipj_1-3/ipj_1-3_catv.html
Question 5.
A new cable modem was shipped to the home of a ITCertKeys user, where it is being installed for the first time.
When a DOCSIS 1.1 compliant cable modem first initializes, (boots up) what does it do?
A. Establishes IP connectivity (DHCP).
B. Determines the time of day.
C. Requests a DOCSIS configuration file from a TFTP server.
D. Scan for a downstream channel and the establishment of timing synchronization with the
CMTS.
E. None of the above.
Answer: D
Explanation:
According to the DOCSIS (Data-over-Cable Service Interface Specifications) when you first power up a cable modem it starts scanning (starting at a low frequency) for a cable signal. When it 'hears' a cable modem stream it listens for a broadcast (from the service provider) which contains information (ie. frequency) needed to talk back with the head end. It then 'talks back' and if it communicates the right authentication information, it is allowed to proceed.
References:
Page 225 of the CCNP Self-Study BCRAN (642-821) ISBN: 1-58720-084-8
http://www.cisco.com/en/US/products/hw/cable/ps2217/products_feature_guide_chapter09186a008019b57f.htm
Question 6.
You are building a small network at your home and you intend on connecting your cable modem to a Cisco router.
Which router interface would you connect the modem to?
A. Synchronous serial
B. Asynchronous serial
C. Ethernet
D. auxiliary
E. BRI
Answer: C
Explanation:
In certain environments where a non Cisco Cable Modem (CM) is used, and the CM is only capable of bridging, a Cisco router such as the Cisco 806 can be connected to the Cable Modem via the Ethernet interface. The routing can then be performed by the Cisco router behind the Cable Modem and the Client PC or Customer Premises Equipment (CPE) will be connected to the Cisco router. Network Address Translation (NAT) can then be configured on the Cisco router.
When the Cisco router is connected behind the Cable Modem the first problem that might be encountered is not obtaining an IP address dynamically on the Cisco router's Ethernet interface. Most Internet Service Providers (ISPs) allow only one host or PC behind the Cable Modem. Some ISPs assign an IP address to the PC based on the host name. Therefore, if you have a Cisco router behind the Cable Modem, then the host name for the router configured using the hostname command should be the same host name given by the ISP.
Example:
Question 7.
When a cable modem is being provisioned to operate with a host system for Internet services, which two options must occur before Layer 1 and 2 connectivity can occur? (Choose two)
A. The cable modem must request an IP address and core configuration information from a
Dynamic Host Configuration Protocol (DHCP) server.
B. The cable modem powering up must scan and lock on the RF data channel in the downstream
path.
C. The modem must request a DOCSIS configuration file from a TFTP server.
D. The cable modem must register with the CMTS.
E. The modem must read specific maintenance messages in the downstream path.
Answer: B, E
Explanation:
According to the DOCSIS (Data-over-Cable Service Interface Specifications) when you first power up a cable modem it starts scanning (starting at a low frequency) for a cable signal. When it 'hears' a cable modem stream it listens for a broadcast (from the service provider) which contains information (ie. frequency) needed to talk back with the head end. It then 'talks back' and if it communicates the right authentication information, it is allowed to proceed. Once these steps are completed, layers 1 and 2 will be operational.
Question 8.
How is cable broadband technology able to transmit downstream and upstream data while at the same time delivering television content?
A. The cable operator uses the VHF hyperband to transmit and receive data signals.
B. The cable operator assigns any available spectrum to data, depending on how its own
television spectrum is being used.
C. The cable operator uses specific bandwidths for data signals specified by DOCSIS.
D. The cable operator places its data signals into clean areas where there is no interference from
noise or other signals.
Answer: C
Explanation:
Developed by CableLabs and approved by the ITU in March 1998, Data Over Cable Service Interface Specification (DOCSIS) defines interface standards for cable modems and supporting equipment. In a cable TV system, signals from the various channels are each given a 6-MHz slice of the cable's available bandwidth and then sent down the cable to your house. In some systems, coaxial cable is the only medium used for distributing signals.
When a cable company offers Internet access over the cable, Internet information can use the same cables because the cable modem system puts downstream data -- data sent from the Internet to an individual computer -- into a 6-MHz channel. On the cable, the data looks just like a TV channel. So Internet downstream data takes up the same amount of cable space as any single channel of programming. Upstream data -- information sent from an individual back to the Internet -- requires even less of the cable's bandwidth, just 2 MHz, since the assumption is that most people download far more information than they upload.
Question 9.
ITCertKeys operates a DSL network. What does the "dsl operating-mode auto" command configure on a Cisco router?
A. It configures a Cisco router to automatically detect the proper modulation method to use when
connecting an ATM interface.
B. It configures a Cisco router to automatically detect the proper DSL type (ADSL, IDSL, HDSL,
VDSL) to use when connecting an ATM interface.
C. It configures a Cisco router to automatically detect the proper encapsulation method to use
when connecting an ATM interface.
D. It configures a Cisco router to automatically detect the proper authentication method to use
when connecting an ATM interface.
E. None of the above
Answer: A
Explanation:
dsloperating-mode auto interface configuration command to specify that the router automatically detect the DSL modulation that the service provider is using and set the DSL modulation to match. An incompatible DSL modulation configuration can result in failure to establish a DSL connection to the DSLAM of the service provider
Example:
Question 10.
ITCertKeys is a DSL service provider using providing xDSL to its customers.
Which statement about xDSL implementations is true?
A. All xDSL standards operate in lower frequencies than the POTS system and can therefore
coexist on the same media.
B. Other than providing higher data rates, HDSL is identical to ADSL.
C. The ADSL standard operates in higher frequencies than the POTS system and can therefore
coexist on the same media.
D. The HDSL standard operates in higher frequencies than the POTS system and can therefore
coexist on the same media.
E. All xDSL standards operate in higher frequencies than the POTS system and therefore can
coexist on the same media.
F. None of the above.
Answer: C
Explanation:
DSL is not a complete end-to-end solution, but rather a physical layer transmission technology similar to dial, cable, or wireless. DSL connections are deployed in the "last mile" of a local telephone network-the local loop. The connection is set up between a pair of modems on either end of a copper wire extending between the customer premises equipment (CPE) and the DSL access multiplexer (DSLAM). A DSLAM is the device located at the central office (CO) of the provider and concentrates connections from multiple DSL subscribers. The term xDSL covers a number of DSL variations, such as ADSL, high-data-rate DSL (HDSL), Rate Adaptive DSL (RADSL), symmetric DSL (SDSL), ISDN DSL (IDSL), and very-high-data-rate DSL (VDSL). DSL types not using the voice frequencies band allow DSL lines to carry both data and voice signals simultaneously (for example, ADSL and VDSL), while other DSL types occupying the complete frequency range can carry data only (for example, SDSL and IDSL). Data service provided by a DSL connection is always-on. The data rate that DSL service can provide depends upon the distance between the subscriber and the CO. The smaller the distance, the higher data rate can be achieved. If close enough to a CO offering DSL service, the subscriber might be able to receive data at rates of up to 6.1 Mbps out of a theoretical 8.448 Mbps maximum.
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Question 1.
You need to implement QoS for the ITCertKeys VOIP network.
Which three statements are true about the data traffic characteristics of voice traffic? (Select three)
A. Voice packets require TCP for rapid retransmission of dropped packets.
B. Latency is not a concern as long as jitter is kept below 30 ms.
C. Voice packets require a fairly constant bandwidth reserved for voice control traffic as well as
for the voice payload.
D. Voice packets do not require a specific type of queuing.
E. Latency must be kept below 150 ms.
F. Voice packets are rather small
Answer: C, E, F
Explanation:
QoS refers to the ability of a network to provide improved service to selected network traffic over various underlying technologies including Frame Relay, ATM, Ethernet and 802.3 networks, SONET, and IP-routed networks.
QoS features provide improved and more predictable network service by offering the following services:
1. Dedicated bandwidth
2. Improved loss characteristics
3. Congestion management and avoidance
4. Traffic shaping
5. Prioritization of traffic
Voice quality is directly affected by all three QoS quality factors such as loss, delay, and delay variation. Loss causes voice clipping and skips. Industry standard codec algorithms can correct for up to 30 ms of lost voice. Cisco Voice over IP (VoIP) technology uses 20 ms samples of voice payload per VoIP packet. Only a single Real Time Transport (RTP) packet could be lost at any given time. If two successive voice packets are lost, the 30 ms correctable window is exceeded and voice quality begins to degrade.
Delay can cause voice quality degradation if it is above 200 ms. If the end-to-end voice delay becomes too long, the conversation sounds as if two parties are talking over a satellite link or a CB radio. The ITU standard for VoIP, G.114, states that a 150 ms one-way delay budget is acceptable for high voice quality. With respect to delay variation, there are adaptive jitter buffers within IP Telephony devices. These buffers can usually compensate for 20 to 50 ms of jitter.
Question 2.
ITCertKeys uses G.711 for the VOIP calls. When analog signals are digitized using the G.711 codec, voice samples are encapsulated into protocol data units (PDUs) involving which three headers? (Select three)
A. UDP
B. RTP
C. IP
D. TCP
E. Compressed RTP
F. H.323
Answer: A, B, C
Explanation:
When a VoIP device, such as a gateway, sends voice over an IP network, the digitized voice has to be encapsulated into an IP packet. Voice transmission requires features not provided by the IP protocol header; therefore, additional transport protocols have to be used. Transport protocols that include features required for voice transmission are TCP, UDP, and RTP. VoIP utilizes a combination of UDP and RTP.
Question 3.
VOIP has been rolled out to every ITCertKeys location.
What are three features and functions of voice (VOIP) traffic on a network? (Select three)
A. Voice traffic is bursty
B. Voice traffic is retransmittable
C. Voice traffic is time-sensitive
D. Voice traffic is bandwidth intensive
E. Voice traffic is constant
F. Voice traffic uses small packet sizes
Answer: C, E, F
Explanation:
The benefits of packet telephony networks include
i. More efficient use of bandwidth and equipment: Traditional telephony networks use a 64-kbps channel for every voice call. Packet telephony shares bandwidth among multiple logical connections.
ii. Lower transmission costs: A substantial amount of equipment is needed to combine 64-kbps channels into high-speed links for transport across the network. Packet telephony statistically multiplexes voice traffic alongside data traffic. This consolidation provides substantial savings on capital equipment and operations costs.
iii. Consolidated network expenses: Instead of operating separate networks for voice and data, voice networks are converted to use the packet-switched architecture to create a single integrated communications network with a common switching and transmission system. The benefit is significant cost savings on network equipment and operations.
iv. Improved employee productivity through features provided by IP telephony: IP phones are not only phones, they are complete business communication devices. They offer directory lookups and access to databases through Extensible Markup Language (XML) applications. These applications allow simple integration of telephony into any business application. For instance, employees can use the phone to look up information about a customer who called in, search for inventory information, and enter orders. The employee can be notified of a issue (for example, a change of the shipment date), and with a single click can call the customer about the change. In addition, software-based phones or wireless phones offer mobility to the phone user.
Question 4.
ITCertKeys is rolling out an H.323 VOIP network using Cisco devices.
Which IOS feature provides dial plan scalability and bandwidth management for H.323 VoIP implementations?
A. Digital Signal Processors
B. Call Routing
C. Gatekeeper
D. Call Admission Control
E. None of the above
Answer: C
Explanation:
Enterprise voice implementations use components such as gateways, gatekeepers, Cisco Unified CallManager, and IP phones. Cisco Unified CallManager offers PBX-like features to IP phones. Gateways interconnect traditional telephony systems, such as analog or digital phones, PBXs, or the public switched telephone network (PSTN) to the IP telephony solution. Gatekeepers can be used for scalability of dial plans and for bandwidth management when using the H.323 protocol.
Question 5.
A Cisco router is being used as a VOIP gateway to convert voice signals in the ITCertKeys network.
What steps are taken when a router converts a voice signal from analog to digital form? (Select two)
A. Quantization
B. Serialization
C. Packetization
D. Sampling
Answer: A, D
Explanation:
Step 1 Sampling: The analog signal is sampled periodically. The output of the sampling is a pulse amplitude modulation (PAM) signal.
Step 2 Quantization: The PAM signal is matched to a segmented scale. This scale measures the amplitude (height) of the PAM signal.
Step 3 Encoding: The matched scale value is represented in binary format.
Step 4 Compression: Optionally, voice samples can be compressed to reduce bandwidth requirements. Analog-to-digital conversion is done by digital signal processors (DSPs), which are located on the voice interface cards. The conversion is needed for calls received on analog lines, which are then sent out to a packet network or to a digital voice interface.
Question 6.
You need to implement the proper IOS tools to ensure that VOIP works over the ITCertKeys network.
Which queuing and compression mechanisms are needed to effectively use the available bandwidth for voice traffic? (Select two)
A. Priority Queuing (PQ) or Custom Queuing (CQ)
B. Real-Time Transport Protocol (RTP) header compression
C. Low Latency Queuing (LLQ)
D. Class-Based Weighted Fair Queuing (CBWFQ)
E. TCP header compression
F. UDP header compression
Answer: D, E
Explanation:
1. Class-based weighted fair queuing (CBWFQ) extends the standard WFQ functionality to provide support for user-defined traffic classes. By using CBWFQ, network managers can define traffic classes based on several match criteria, including protocols, access control lists (ACLs), and input interfaces. A FIFO queue is reserved for each class, and traffic belonging to a class is directed to the queue for that class. More than one IP flow, or "conversation", can belong to a class. Once a class has been defined according to its match criteria, the characteristics can be assigned to the class. To characterize a class, assign the bandwidth and maximum packet limit. The bandwidth assigned to a class is the guaranteed bandwidth given to the class during congestion. CBWFQ assigns a weight to each configured class instead of each flow. This weight is proportional to the bandwidth configured for each class. Weight is equal to the interface bandwidth divided by the class bandwidth. Therefore, a class with a higher bandwidth value will have a lower weight. By default, the total amount of bandwidth allocated for all classes must not exceed 75 percent of the available bandwidth on the interface. The other 25 percent is used for control and routing traffic. The queue limit must also be specified for the class. The specification is the maximum number of packets allowed to accumulate in the queue for the class. Packets belonging to a class are subject to the bandwidth and queue limits that are configured for the class.
2. TCP/IP header compression subscribes to the Van Jacobson Algorithm defined in RFC 1144. TCP/IP header compression lowers the overhead generated by the disproportionately large TCP/IP headers as they are transmitted across the WAN. TCP/IP header compression is protocol-specific and only compresses the TCP/IP header. The Layer 2 header is still intact and a packet with a compressed TCP/IP header can still travel across a WAN link. TCP/IP header compression is beneficial on small packets with few bytes of data such as Telnet. Cisco's header compression supports Frame Relay and dial-on-demand WAN link protocols. Because of processing overhead, header compression is generally used at lower speeds, such as 64 kbps links.
Question 7.
You want to ensure the highest call quality possible for all VOIP calls in the ITCertKeys network.
Which codec standard would provide the highest voice-quality, mean opinion score (MOS)?
A. G.711, PCM
B. G.729, CS-ACELP
C. G.729A, CS-ACELP
D. G.728, LDCELP
E. None of the above
Answer: A
Explanation:
When a call is placed between two phones, the call setup stage occurs first. As a result of this process, the call is logically set up, but no dedicated circuits (lines) are associated with the call. The gateway then converts the received analog signals into digital format using a codec, such as G.711 or G.729 if voice compression is being used. When analog signals are digitized using the G.711 codec, 20 ms of voice consists of 160 samples, 8 bits each. The result is 160 bytes of voice information. These G.711 samples (160 bytes) are encapsulated into an RTP header (12 bytes), a UDP header (8 bytes), and an IP header (20 bytes). Therefore, the whole IP packet carrying UDP, RTP, and the voice payload has a size of 200 bytes. When G.711 is being used, the ratio of header to payload is smaller because of the larger voice payload. Forty bytes of headers are added to 160 bytes of payload, so one-fourth of the G.711 codec bandwidth (64 kbps) has to be added. Without Layer 2 overhead, a G.711 call requires 80 kbps.
Question 8.
When a router converts analog signals to digital signals as part of the VoIP process, it performs four separate steps.
From the options shown below, which set of steps contains the steps in their correct sequence?
A. encoding
quantization
optional compression
sampling
B. optional compression
encoding
sampling
quantization
C. sampling
quantization
encoding
optional compression
D. optional compression
sampling
encoding
quantization
E. sampling
quantization
optional compression
encoding
F. encoding
optional compression
quantization
sampling
G. None of the above
Answer: C
Explanation:
Step 1 Sampling: The analog signal is sampled periodically. The output of the sampling is a pulse amplitude modulation (PAM) signal.
Step 2 Quantization: The PAM signal is matched to a segmented scale. This scale measures the amplitude (height) of the PAM signal.
Step 3 Encoding: The matched scale value is represented in binary format.
Step 4 Compression:
Optionally, voice samples can be compressed to reduce bandwidth requirements. Analog-to-digital conversion is done by digital signal processors (DSPs), which are located on the voice interface cards. The conversion is needed for calls received on analog lines, which are then sent out to a packet network or to a digital voice interface.
Question 9.
ITCertKeys has determined that during its busiest hours, the average number of internal VoIP calls across the WAN link is four (4). Since this is an average, the WAN link has been sized for six (6) calls with no call admission control.
What will happen when a seventh call is attempted across the WAN link?
A. The seventh call is routed via the PSTN.
B. The call is completed, but all calls have quality issues.
C. The call is completed but the seventh call has quality issues.
D. The call is denied and the original six (6) calls remain.
E. The call is completed and the first call is dropped.
F. None of the above.
Answer: B
Explanation:
IP telephony solutions offer Call Admission Control (CAC), a feature that artificially limits the number of concurrent voice calls to prevent oversubscription of WAN resources. Without CAC, if too many calls are active and too much voice traffic is sent, delays and packet drops occur. Even giving Real-Time Transport Protocol (RTP) packets absolute priority over all other traffic does not help when the physical bandwidth is not sufficient to carry all voice packets. Quality of service (QoS) mechanisms do not associate individual RTP packets with individual calls; therefore, all RTP packets are treated equally. All RTP packets will experience delays, and any RTP packets may be dropped. The effect of this behavior is that all voice calls experience voice quality degradation when oversubscription occurs. It is a common misconception that only calls that are beyond the bandwidth limit will suffer from quality degradation. CAC is the only method that prevents general voice quality degradation caused by too many concurrent active calls.
Question 10.
While planning the new ITCertKeys VOIP network, you need to determine the size of the WAN links to use. To do this, you need to calculate the bandwidth required by each call.
Which three pieces of information are used to calculate the total bandwidth of a VoIP call? (Select three)
A. The serialization of the interface
B. The quantization
C. The TCP overhead
D. The packetization size
E. The UDP overhead
F. The packet rate
Answer: D, E, F
Explanation:
Packet rate: Packet rate specifies the number of packets sent in a certain time interval. The packet rate is usually specified in packets per second (pps). Packet rate is the multiplicative inverse of the packetization period. The packetization period is the amount of voice (time) that will be encapsulated per packet, and is usually specified in milliseconds. Packetization size: Packetization size specifies the number of bytes that are needed to represent the voice information that will be encapsulated per packet. Packetization size depends on the packetization period and the bandwidth of the codec used. IP overhead: IP overhead specifies the number of bytes added to the voice information during IP encapsulation. When voice is encapsulated into Real-Time Transport Protocol (RTP), User Datagram Protocol (UDP), and IP, the IP overhead is the sum of all these headers.
Data link overhead: Data-link overhead specifies the number of bytes added during data-link encapsulation. The data-link overhead depends on the used data-link protocol, which can be different per link. Tunneling overhead: Tunneling overhead specifies the number of bytes added by any security or tunneling protocol, such as 802.1Q tunneling, IPsec, Generic Route Encapsulation (GRE), or Multiprotocol Label Switching (MPLS). This overhead must be considered on all links between the tunnel source and the tunnel destination.
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Question 1.
Which service component within the design phase does the following describe? Consider the customer's defined business requirements and the associated performance, availability, resiliency, maintainability, resource capacity, and security criteria used to measure and assure the delivery of the required services.
A. Staging Plan
B. Implementation Plan
C. Business Plan
D. Detailed Design Validation
E. Project Kick-off
Answer: B
Question 2.
Which service component within the prepare phase validates the features and functionality documented in the high-level design of a solution?
A. Proof of Concept
B. High-level Design Development
C. Business Case Development
D. Business Requirements Development
E. Operations Technology Strategy Development
F. Technology Strategy Development
Answer: A
Question 3.
In the implement phase, project close-out involves which of the following tasks?
A. deliver education based on Staff Planning Development reports
B. conduct Engagement Profitability Assessment
C. execute network migration plan
D. customize ongoing support hand-off kit
Answer: B
Question 4.
In the implement phase, project close-out involves which of the following tasks?
A. deliver education based on Staff Planning Development reports
B. customize ongoing support hand-off kit
C. conduct Engagement Profitability Assessment
D. execute network migration plan
Answer: C
Question 5.
In the design phase, performing a needs analysis to identify the resource requirements and skills needed to deliver and support a network infrastructure is an activity of which service component?
A. Implementation Kick-off Meeting
B. Implementation Plan
C. Project Kick-off
D. Staging Plan
E. Migration Plan
F. Staff Plan Development
Answer: F
Question 6.
In the implement phase, solution implementation involves which of the following task?
A. Execute test cases
B. Configure core products
C. Perform preliminary Site Assessment
D. Analyze high-level design and technology requirements of the customer
Answer: B
Question 7.
Which one of the following describes the task for completing an operations readiness assessment in the plan phase?
A. determining network elements that will be tested
B. reviewing hardware and software configuration staging plan
C. entering documentation into knowledge management system
D. developing backup/recovery plan
E. creating an escalation plan
F. obtaining and reviewing operation procedures and policies
Answer: F
Question 8.
In the implement phase, solution implementation involves which of the following task?
A. perform preliminary Site Assessment
B. configure core products
C. execute test cases
D. analyze high-level design and technology requirements of the customer
Answer: B
Question 9.
Which of the following definitions best describes services stack within the Cisco Lifecycle Services approach?
A. the minimum set of services that a customer needs to successfully deploy and operate a Cisco
technology or solution
B. the required set of services needed to successfully deploy and support Cisco Advanced
Technologies
C. the identification of Advanced Technologies to best support business requirements and
objectives
D. the minimum set of services required to operate and optimize Cisco Advanced Technologies
Answer: A
Question 10.
Which of the following definitions best describes business requirements development within the prepare phase?
A. a set of service component activities that assesses and documents the business requirements
of a customer
B. part of the systems design activity that identifies and documents business requirements to help
deploy network technologies
C. part of the high-level design activity that addresses business and technical requirements of the
customer
D. a service component activity that analyzes business requirements and recommends the
appropriate technology strategy
Answer: A
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