Home > Design Fundamentals

# Design Fundamentals

September 13th, 2010 in CCDA Go to comments

Here you will find answers to Design Fundamentals Questions

Question 1

Which of these is the equation used to derive a 64 Kbps bit rate?

A. 2×8 kHz x 4-bit code words
B. 8 kHz x 8-bit code words
C. 2 x 4-bit code words x 8 kHz
D. 2×4 kHz x 8-bit code words

Explanation

While the human ear can sense sounds from 20 to 20,000 Hz, and speech encompasses sounds from about 200 to 9000 Hz, the telephone channel was designed to operate at about 300 to 3400 Hz. This economical range carries enough fidelity to allow callers to identify the party at the far end and sense their mood. Nyquist decided to extend the digitization to 4000 Hz, to capture higher-frequency sounds that the telephone channel may deliver. Therefore, the highest frequency for voice is 4000 Hz. According to Nyquist theory, we must double the highest frequency, so 2x4kHz = 8kHz.

Each sample will be encoded into a 8-bit code. Therefore 8kHz x 8-bit code = 64 Kbps (notice about the unit Kbps: 8kHz = 8000 samples per second so 8000 x 8-bit = 64000 bit per second = 64 Kilobit per second = 64 Kbps)

Note:

Nyquist theory:

“When sampling a signal (e.g., converting from an analog signal to digital), the sampling frequency must be greater than twice the bandwidth of the input signal in order to be able to reconstruct the original perfectly from the sampled version.”

Question 2

Which three of these are components of the North American Numbering Plan? (Choose three)

A. Numbering Plan Area
B. country code
C. prefix
D. zone
E. line number
F. trunk channel

Explanation

NANP has the address format of NXX-NXX-XXXX, where N is any number from 2 to 9 and X is any number from 0 to 9. The ﬁrst three digits identify the numbering plan area and are commonly called the area code. The address is further divided into the office code (also known as prefix) and line number. The prefix is three digits, and the line number is four digits. The line number identifies the phone.

Question 3

A customer has the following Enterprise Campus design requirements:

at least 10 Gbps of bandwidth
network runs of up to 40km
no concern for transmission medium cost

Which transmission medium should you recommend to this customer?

A. shielded twisted pair
B. unshielded twisted pair
C. multimode fiber
D. single-mode fiber
E. wireless

Explanation

Below is the comparison of transmission media

 Media Bandwidth Distance Twisted pair Up to 1 Gbps 100 m Multimode fiber Up to 1 Gbps 2 km (FE) 550 m (GE) Single-mode fiber 10 Gbps 90 km (FE) 40 km (GE) Wireless 54 Mbps (27 Mbps effective) 500 m at 1 Mbps

(Reference from CCDA Official Exam Certification Guide. Some other books have different figures but we should answer it according to the “Official” book)

Question 4

In the Cisco branch office design, what categorizes an office as large?

A. between 50 and 100 users and a three-tier design
B. between 50 and 100 users and a single-tier design
C. between 100 and 200 users and a two-tier design
D. between 100 and 200 users and a three-tier design
E. over 200 users and a two-tier design

Question 5

Which layer is the distribution layer?

A. Layer A
B. Layer B
C. Layer C
D. Layers A and B form a consolidated core and distribution layer

Question 6

Which two implementation plan principles best describe how to deal with potential failures?(Choose two)

A. A good implementation plan.
B. A successful test network test.
C. A test should be included at every step.
D. A detailed rollback procedure for each implementation step.
E. A table of failure points, rollback steps, and estimated rollback times.

Question 7

Refer to the exhibit.

A standard, Layer 2 campus network design is pictured. Which numbered box represents the distribution layer?

A. #1
B. #2
C. #3
D. #4

Question 8

Which three pieces of information should be documented for each step of each phase in a design implementation plan? (Choose three)

A. step description
B. design document references
C. easy guidelines in case of failure
D. estimated implementation time
E. simple implementation guidelines
F. estimated rollback time in case of failure

Question 9

Which three terms describe the primary functions of the distribution layer of the campus network design hierarchy? (Choose three)

A. provides end-user connectivity
B. provides high speed transport
C. provides QoS services
D. enforces security policies
E. provides WAN connections
F. connects access devices to the core backbone

Question 10

Refer to the exhibit

Which two statements correctly identify the layers of the Enterprise Campus module? (Choose two)

A. A is the Server Farm layer and C is the Campus Core layer.
B. A is the Server Farm layer and D is the Building Access layer.
C. B is the Campus Core layer and C is the Building Distribution layer.
D. B is the Building Distribution layer and C is the Campus Core layer.
E. A is the Internet Connectivity layer and B is the Campus Core layer.
F. B is the Building Distribution layer and D is the Building Access layer.

Question 11

Refer to the exhibit.

Which statement accurately represents the characteristics of the core layer in this design?

A. QoS should be performed only in the core.
B. Load balancing should never be implemented or used in the core.
C. Access lists should be used in the core to perform packet manipulation.
D. It is acceptable to use a partial mesh in the core if it is connected to each device by multiple paths.

Question 12

Refer to the exhibit

Which element or elements of the existing network infrastructure does this network map emphasize?

A. network services
B. network protocols
C. the OSI data link layer
D. network applications

Question 13

Which two of the following are benefits of using a modular approach to network design? (Choose two)

A. improves flexibility
B. facilitates implementation
C. lowers implementation costs
D. improves customer participation in the design process

1. October 10th, 2010

got perfect score.THANKS TUT. I hope youll create one for ARCH (642-873 too.

2. October 23rd, 2010

I just signed up to your blogs rss feed. Will you post more on this subject?

3. October 24th, 2010

this was a really nice post, thanks

4. October 26th, 2010

Hey, I can’t view your site properly within Opera, I actually hope you look into fixing this.

5. December 5th, 2010

How many Drag and Drop questions are on the exam…?

6. January 29th, 2011

great stuff all questions were just easy for me to answer. all question came from here.

7. January 30th, 2011

@ Praveen
Is there any simulation with this exam?

8. March 30th, 2011

passed CCDA with 987!
all questions good from here

9. March 30th, 2011

no sims

10. April 8th, 2011

Hi Guys,

Are the materials in here still valid for 640-864?

11. December 13th, 2012

Q13. Just confirming that this is the correct answer. See this ref.

http://www.ciscopress.com/articles/article.asp?p=1073230&seqNum=2

Which says:

The modularity built into the architecture allows flexibility in network design and facilitates implementation and troubleshooting

Thanks DSTUT

12. March 29th, 2013

Are all these questions still current?