www.vustudents.ning.com

We non-commercial site working hard since 2009 to facilitate learning Read More. We can't keep up without your support. Donate.

# Data Communication CS601 - Assignment No. 02 Solution and discussion Semester: Fall 2013 Due Date: 6/12/2013

 Uploading instructions:   Your assignment must be in Microsoft Word format. (Any other formats like scan images, PDF, Zip, rar, bmp, etc will not be accepted). Save your assignment with your ID (e.g. bc020200786.doc). No assignment will be accepted through email.   Rules for Marking:   It should be clear that your assignment will not get any credit if: The assignment is submitted after due date. The submitted assignment does not open or file is corrupted. Your assignment is copied from internet, handouts or from any other student

(Strict disciplinary action will be taken in this case).

Question 1:   (10 Marks)

You are required to represent the data stream 1001101001 using the following encoding schemes on different graphs separately.

• NRZ-L
• NRZ-I

Question 2:   (5 Marks)

a) A periodic signal has a bandwidth of 700 Hz and its lowest frequency is 200 Hz; find out its highest frequency with all necessary steps.

b) Consider the following sine wave, and calculate its time period and frequency.

Question 3:   (5 Marks)

Suppose a message travels from device A to B in OSI model. Headers and trailers are added to the message before it reaches the destination B. Considering the given scenario, you are required to identify:

• The sequence of OSI layers in which headers and trailers are added at device A.
• The sequence of OSI layers in which headers and trailers are removed at device B.

NOTE: Every student should provide his/her own work, exact copying of the assignment (or some portion of the assignment) from the internet or other students will lead to copy case and zero marks will be awarded. Do not put any query on MDB about this assignment, if you have any query then email at cs601@vu.edu.pk.

Views: 15446

Attachments:

### Replies to This Discussion

Lets Discuss

ggggggggggggggggggggggggggggggggggggg

HMMMM, MAZA AAE GA.

Q3

Our main purpose here discussion not just Solution

We are here with you hands in hands to facilitate your learning and do not appreciate the idea of copying or replicating solutions.

# NRZ

Short for NonReturn-to-Zero, NRZ is a commonly used method of encoding a data stream into a voltage waveform. In NRZ encoding, the binary zero is turned into a low voltage, and one is turned into a high voltage.

"Non return-to-zero-level (NRZ-L) is a data encoding scheme in which a negative voltage is used to represent binary one and a positive voltage is used to represent binary zero. As with NRZ-L, NRZI maintains a constant voltage pulse for the duration of a bit time. The data themselves are encoded as the presence or absence of a signal transition at the beginning of the bit time. A transition (low to high or high to low) at the beginning of a bit time denotes a binary 1 for that bit time; no transition indicates a binary 0."

Just an idea pic

What is the major difference between NRZ-L and NRZI?

"Non return-to-zero-level (NRZ-L) is a data encoding scheme in which a negative voltage is used to represent binary one and a positive voltage is used to represent binary zero. As with NRZ-L, NRZI maintains a constant voltage pulse for the duration of a bit time. The data themselves are encoded as the presence or absence of a signal transition at the beginning of the bit time. A transition (low to high or high to low) at the beginning of a bit time denotes a binary 1 for that bit time; no transition indicates a binary 0."

The frequency of a wave is the amount of time the wave goes through a complete cycle in a second. The unit of frequency is Hertz, which literally means "per second". So if the frequency of a wave is 30 Hz, the wave goes through 30 complete cycles in one second.

The simplest way to calculate frequency using time would be to count the amount of complete cycles that the wave goes through in a second. Or, if it would be easier, you could count the amount of cycles in a minute and divide by 60 (or hour and divide by 3600, etc.)

1

2

3

4

5

## Latest Activity

QANTA NASEER, Fatima FF, Nadeem Sattar and 1 more joined Virtual University of Pakistan
11 hours ago
Ajeeha and Adeel are now friends
18 hours ago
yesterday
yesterday
yesterday
yesterday
yesterday
yesterday