CROWDMARK
CS 456/656 Midterm Exam
Please print in pen:
Waterloo Student ID Number:
WatIAM/Quest Login Userid:
Examination
Midterm
Spring 2024
Times: Friday 2024-06-14 at 18:30 to 20:00 (6:30 to 8PM) CS 456/656
Duration: 1 hour 30 minutes (90 minutes)
Exam ID: 5805955
Sections: CS 456 LEC 001,002 Special Materials
CS 656 LEC 001,002
Instructors: Abdalla Mohamed Hussein, Noura Limam Candidates may bring only the listed aids.
· Calculator - Pink Tie
Calculators are accepted
Number of Exam Pages (including this cover sheet): 12
Marking Scheme:
-I- /17
-II- /53
TOTAL /70
!
!
CS 456/656 Spring 2024 Midterm
© 2024 University of Waterloo Page 1 of 12
, CROWDMARK
"#"! [17 Marks] True/False – Assess whether the following statements are true or false by
circling the corresponding letter (T or F). Each question is worth 1 point.
1) Internet is a circuit-switched network. T F
2) The propagation delay on a link increases proportionally with the length of the link. T F
The queuing delay in a router’s output link increases with the traffic intensity on T F
3) that link.
A Distributed Denial of Service (DDoS) attack cannot be run over TCP because T F
4) TCP is a point-to-point protocol.
5) Unlike HTTP/1, HTTP/2 runs on top of UDP. T F
HTTP proxy servers only request web objects from origin servers when the T F
6) requestor cannot be authenticated.
In HTTP/1 with persistent connections, only one TCP connection is required to T F
7) download any web page regardless of the number of referenced objects and their
location.
With non-persistent connections between browser and origin server, it is possible T F
8) for a single TCP segment to carry two distinct HTTP/1 request messages.
9) HTTP is a stateless application layer protocol. T F
In HTTP, requests and responses are sent and received on different sockets T F
10) running on the client host.
SMTP and HTTP can both be used to download your emails to your machine from T F
11) your email server.
12) SMTP runs on top of UDP for faster email delivery. T F
13) In SMTP, the body of an email and the attachment files will be sent on separate T F
TCP connections.
14) In SMTP, two emails can be pushed over the same TCP connection. T F
15) In DNS, all requests must pass through a root name server. T F
16) DNS caching decreases the number of DNS requests to root name servers. T F
17) Root Name Servers treat queries from a requesting host typically recursively. T F
!
CS 456/656 Spring 2024 Midterm
© 2024 University of Waterloo Page 2 of 12
CS 456/656 Midterm Exam
Please print in pen:
Waterloo Student ID Number:
WatIAM/Quest Login Userid:
Examination
Midterm
Spring 2024
Times: Friday 2024-06-14 at 18:30 to 20:00 (6:30 to 8PM) CS 456/656
Duration: 1 hour 30 minutes (90 minutes)
Exam ID: 5805955
Sections: CS 456 LEC 001,002 Special Materials
CS 656 LEC 001,002
Instructors: Abdalla Mohamed Hussein, Noura Limam Candidates may bring only the listed aids.
· Calculator - Pink Tie
Calculators are accepted
Number of Exam Pages (including this cover sheet): 12
Marking Scheme:
-I- /17
-II- /53
TOTAL /70
!
!
CS 456/656 Spring 2024 Midterm
© 2024 University of Waterloo Page 1 of 12
, CROWDMARK
"#"! [17 Marks] True/False – Assess whether the following statements are true or false by
circling the corresponding letter (T or F). Each question is worth 1 point.
1) Internet is a circuit-switched network. T F
2) The propagation delay on a link increases proportionally with the length of the link. T F
The queuing delay in a router’s output link increases with the traffic intensity on T F
3) that link.
A Distributed Denial of Service (DDoS) attack cannot be run over TCP because T F
4) TCP is a point-to-point protocol.
5) Unlike HTTP/1, HTTP/2 runs on top of UDP. T F
HTTP proxy servers only request web objects from origin servers when the T F
6) requestor cannot be authenticated.
In HTTP/1 with persistent connections, only one TCP connection is required to T F
7) download any web page regardless of the number of referenced objects and their
location.
With non-persistent connections between browser and origin server, it is possible T F
8) for a single TCP segment to carry two distinct HTTP/1 request messages.
9) HTTP is a stateless application layer protocol. T F
In HTTP, requests and responses are sent and received on different sockets T F
10) running on the client host.
SMTP and HTTP can both be used to download your emails to your machine from T F
11) your email server.
12) SMTP runs on top of UDP for faster email delivery. T F
13) In SMTP, the body of an email and the attachment files will be sent on separate T F
TCP connections.
14) In SMTP, two emails can be pushed over the same TCP connection. T F
15) In DNS, all requests must pass through a root name server. T F
16) DNS caching decreases the number of DNS requests to root name servers. T F
17) Root Name Servers treat queries from a requesting host typically recursively. T F
!
CS 456/656 Spring 2024 Midterm
© 2024 University of Waterloo Page 2 of 12
