Self-Assessment Quizzes Chapter 2 MC，T&F

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1.
The transfer of an html file from one host to another is
loss-tolerant and time sensitive
loss-intolerant and time sensitive
none of the above
loss-intolerant and time insensitive
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2.
A browser will generate header lines as a function of
browser type and version
whether the browser has a cached version of the requ- ested bject
all of the above
user configuration of browser
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3.
Suppose a client sends an HTTP
request message with the If-modified-
since: header.Suppose the object in a
server has not changed since the last
time a client retrieved the object.
Then the server will send a response
message with the status code:
none of the above
304 Not Modified
404 Not Found
200 OK
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4.
Suppose the hit rate is .5 (instead
of .4) in the caching example in the
text. Then the average delay is
between 1.0 and 1.1 seconds
greater than two seconds
none of the above
between 1.2 and 1.3 seconds
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5.
SMTP is used to
all of the above
to transfer messages from mail server to a user agent
to define the format of message headers
to transfer messages from one mail server to another
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6.
Suppose a DNS resource record
has Type=MX. Then
Value is the hostname of the mail server that has the alias hostname Name.
Value is the hostname of the DNS server that is authoritative for Name.
none of the above
Value is the IP address of the mail server that has the alias hostname Name.
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7.
Local DNS name servers
cache resource records and never discard them
obtain resource records from Web caches
cache resource records, but discard them after a period of time that is on the order of a few days
never cache resource records
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8.
Streams are not needed in which
of the following programs:
UDPclient
TCPclient
TCPserver
UDPserver
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9.
Consider the minimum time for
P2P filedistribution, as discussed
in Section 2.6.Suppose the upload
rate of the server is10 Mbps, the
upload rates of all peers is 1 Mbps,
and the download rates of all
peers is 10 Mbps. Further suppose
that there are 100 peers and the
file is 100 million bits. The minimum
distribution time is
approximately 1 second
approximately 10 seconds
approximately 100 seconds
approximately 1000 seconds
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10.
For BitTorrent, which of the
following is true:
Among the chunks that a peer does not have, the peer will request chunks that appear to be relatively rare in the torrent.
All of the above.
At a given instant of time, a peer A may upload to a peer B, even if peer B is not sending anything to A.
Although a peer may have 50 concurrent TCP connections with other peers, at any given instant of time it sends data to less than 10 other peers.
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11.
A server can use cooki-es to
determine a user's postal address
without the user's consent.
True
False
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12.
The Web typically sends multiple
objects in a Web page within a
multipart MIME message.
True
False
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13.
It is possible for a mail client to
send e-mail messages over HTTP
rather than SMTP.
True
False
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14.
If a POP3 client does not send
the dele command, copies of the
messages that the client has retrieved
remain in the mail server.
True
False
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15.
With SMTP, it is possible to send
multiple mail messages over the same
TCP connection.
True
False
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16.
DNS lookups often involve a
combination of recursive and
iterative queries.
True
False
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17.
With non-persistent connections
between browser and origin server,
it is possible for a single TCP segment
to carry two distinct HTTP request messages.
True
False
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18.
The Date: header in the HTTP
response message indicates when
the object in the response was last
modified.
True
False
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19.
In BitTorrent, a peer’s instantan-
eous download rate can never exceed
its instantaneous upload rate.
True
False
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20.
Skype relay nodes are typically
peers under the control of Skype users.
True
False
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