Marking Scheme

Marks were assigned as follows:

			   Final Exam

marked out of 32:

Question 1 (3 marks)

1 for off-hook
1 for on-hook
1 for "...separates directions..."

Question 2 (3 marks)

1 for downstream
2 for 11~dB (method, answer)

Question 3 (3 marks)

1 for 2.56us
1 for 333kHz (0.5 if got 342 including framing symbols)
1 for 264 Mbps

Question 4 (2 marks)

2 (1 for 16-way result, 1 for method)

Question 5 (3 marks)

1 for 34 bytes
1 for one cell (or correct answer based on above)
1 for 6 bytes padding (or correct answer based on reasonably close previous answers)

Question 6 (3 marks)

1 for removing header/trailer (answer must be unambiguous)
1 for removing 2 escape characters
1 for XORing escaped values with 0x20

Question 7 (4 marks)

1 for traceroute
1 for finding route to destination
1 for ttl exceeded and echo response (ping response)
1 for responses disabled

Question 8 (3 marks)

\item SYN+ACK TCP flag field bits
\item source=80 and destination=5000 port numbers
\item Acknowledgement field value=1001

Question 9 (8  marks)

a: 2: 1 for 1MHz, 1 for 11bits
b: 1: 1 for 1244 Mbs
c: 1: 1 for no slips & why
d: 2: 1 for 3 options(12,15,14), 1 for the values (also OK if only 1st option: grammar error)
e: 1: 1 for NS and A lines
f: 1: 1 for more RTP and explanation


			  Mid-Term Exam

marked out of 11:

q1

(a) 1 for "off-hook" or "current flow" or "seized" or "loop start"
(b) 1 for 350+440 Hz (dial tone frequencies)
(c) 1 for [pulse] dialing (*not* DTMF)
(d) 1 for POTS or pulse or seize+pulse+call progress (0 for DTMF)

q2

1 for fibre loss calculation (0.3 * distance)
1 for splitter loss (15 or 18 dB) or for dividing power in mW by 32 or 64)
1 for a correct equation calculating the required transmit power
1 for the correct numerical answer (see solutions)

q3

1 for correct number of bits (12 or 13)
1 for number of AMI line coding violations (2)
1 for correct bit values (see solutions)


			   Assignments

Only the 4 highest assignment marks were counted.

one mark was assigned for each of the following:

			  Assignment 1

marked out of 11:

q1 late 1800's for POTS, 1990's for ADSL and DOCSIS, 2000's for PON
q1 Telus and Shaw
q2 1: condition 3 (620 Hz, busy)
q2 3: action 2 (dial the number)
q2 7: action 3 (play the ad)
q4 13 dB
q5 interference at CMTS/upstream
q6 (b) 46 and 20 dB gains
q6 (e) 16 or 17 amplifiers on each side
q7 rows=45
q7 columns=n=22

			  Assignment 2

marked out of 8:

q1c LPF at 4kHz
q2 approx 158 to 162 
q3 ~78kHz spacing, 
q3 ~23Mb/s rate
q4 40km, 
q4 5000km^2
q5a 108dB
q5c 48kHz, 

			  Assignment 3

marked out of 7:

q2	0.05ppm
q3	8 bytes of padding
q8d	only TCP and ICMP
q9	cidr /19 is 255.255.224.0
q10a,c	private, routable
q11b	default, 192.168.0.1
q14	TLV = 0x0b, N, characters

			  Assignment 4

marked out of 5:

q1 bcit.ca. IN MX 10 outlook.live.net.
q2 authoritative
q4 scheme is ftp:
q5 application/data: arbitrary data
q6 screenshot

			  Assignment 5

marked out of 6:

q1a 192.168.1.1 MAC ...56:07
q2  correct header values (except checksum)
q2  correct checksum
q5 A, C, C
q6 7 packets, 140ms or 3 packets, 60ms
q7 (c) far-end echo canceller

			      Labs

For labs without Pre-Labs the report counts for 25% and lab
completion counts for 75% of that lab's mark.  Each lab is given
equal weight.

Lab 1 Pre-Lab

marked out of 4:

1 for minimum duration = 50ms
1 for resolution = 20Hz
1 for 1/697=1.4ms
1 for 50ms/1.4ms ~ 35

Lab 1 Lab Report

marked out of 7:

1 for identification (course name and number, lab number and
  title, name and ID, date)
1 for waveform file name
1 for explanation that frequency measurement doesn't work 
  because signal contains two frequecies
1 for screen shot including frequency cursors
1 for correct tone frequencies
1 for correct digit
1 for amplitude difference

Lab 2 Pre-Lab

marked out of 2:

1 for a reasonable attempt at writing a Matlab function
1 for calculation of quantization noise power: q=2/256, q^2/12 = 5E-6*R watts

Lab 2 Report

marked out of 4:

1 for plots of uncompressed and compressed signal
1 for explanation that companded waveform has higher amplitudes
1 for summary table including:
  four columns (measurement, with, without, ratio in dB)
  three rows: (S, N, SNR)
1 for a reasonable explanation of effect of companding

Lab 3 Pre-Lab

marked out of 7:

1 for sample rate = 2.208 MHz
1 for duration = (512+32)/fs = 246 us
1 for subcarrier frequency range 1xx to 9yy
1 for PSD = (0.1/sqrt(2))^2/100/4312.5 W/Hz = -79dBW/Hz = -49dBm/Hz
  about 13dB less than -36.5dBm/Hz
1 for (512+32) samples * 2 bytes = 1088 bytes
1 for (0.1/sqrt(2))^2 * number of tones ~= 1 Vrms (for 185 tones)
1 for Matlab code with changes (to at least the subcarriers)

Lab 3 Report

marked out of 4:

1 for Matlab code without obvious errors
1 for screen capture showing approximately correct RMS voltage (~1V)
1 for spectrum display showing cursors at approximately correct frequencies
1 for a comparison of expected/measured RMS voltages and frequencies

Lab 4 Report (DHCP, no Pre-Lab):

marked out of 6:

q1 UDP or TCP
q2 timing diagram with packet types and port numbers
q3 Ethernet address of host
q5 transaction ID and purpose
q10 purpose of router (gateway) and netmask in DHCPOFFER
q12 purpose and length of lease time

Lab 5 Report (DNS, no Pre-Lab)
marked out of 7:

q1: nslokoup with IP result
q2: nslookup with -type=NS
q4: UDP
q5: src & dest port = 53
q10: no new DNS query
q16: 'NS' query to default server
q20: 'A' query to non-default server

Lab 6 Report (IOS, no Pre-Lab)

marked out of 4:

1 for ID
1 for topology screen capture
1 for screen capture of configuration
1 for wireshark capture of ping request and response


Lab 7 Report (OSPF, no Pre-Lab)

marked out of 7:

- screen capture of topology
- two "sh ip route" results showing different routes to 3.0.0.0/8
- two traceroute results showing two different routes to 3.0.0.3
- hello packet capture
- LSA packet capture
- 2 metrics included in LSA
- submitted wireshark capture file