Zusammenfassung der Ressource
Frage 1
Frage
What is the meaning of an acknowledgement number N in the TCP header? Check all that apply:
Antworten
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The number of correctly received TCP segments
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All TCP segments up to number N-1 are received correctly
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All bytes up to number N-1 are received correctly
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The size of the available receive buffer in bytes
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The sequence number of the first byte in the next expected segment
Frage 2
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Over which portions is the checksum within the TCP header calculated?
Antworten
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TCP header + TCP data
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IP header + TCP header + TCP data
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Pseudo IP header + TCP header
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Pseudo IP header + TCP header + TCP data
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Ethernet header + Pseudo IP header + TCP header + TCP data
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Ethernet header + Pseudo IP header + TCP header
Frage 3
Frage
Which standard applications use TCP? Check all that applies:
Antworten
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TFTP
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FTP
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LDAP
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HTTP
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HTTPS
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Email (SMTP, POP, IMAP)
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ARP
Frage 4
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How is the application process addressed? Check all that applies:
Frage 5
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List at least 3 internet applications and their corresponding port numbers
HTTP - 80
Telnet - 23
SMTP - 25
SSH - 22
DNS - 53
IMAP - 220
Frage 6
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Which statements on port numbers are correct? Check all that applies:
Antworten
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TCP/IP port numbers are 32 bit numbers
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TCP/IP port numbers are 2 byte numbers
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A HTTP-client uses port number 80
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A HTTP-client may use port number 8000
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A HTTP-client may use port number 80 000
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The default HTTP server port number is 80
Frage 7
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Which statements on well-known and ephemeral ports are correct? Check all that applies:
Antworten
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80 is a well-known port number
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1000 is an ephemeral port number
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Well-known ports are uniquely assigned by IANA to certain application layer services at servers
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Registered port numbers can be used by internet clients
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Client processes must use well-known ports
Frage 8
Frage
Which statements on sockets are correct? Check all that applies:
Antworten
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Each side of a TCP connection has a socket which can be identified by the following triple
< TCP, TCP segment number, IP address >
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Each side of a TCP connection has a socket which can be identified by the following triple
< Port number, TCP segment number, IP address >
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Each side of a TCP connection has a socket which can be identified by the following triple
< TCP, IP address, port number >
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A logical TCP connection between a server and client is identified by
< TCP segment number, local IP address, local port, ACK number, remote IP address >
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A logical TCP connection between a server and client is identified by
< TCP, local IP address, local port, remote IP address, remote port >
Frage 9
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Of what functions consists a UDP API?
Creation of new receive ports
Receive operation that returns
Data Bytes
Source Port
Source IP Address
Send operation that returns
A pointer to the data bytes
The destination port
The destination IP address
Frage 10
Frage
List at least 4 TCP socket API function calls:
Open (establishes TCP connection)
Send (sends data from buffer via TCP connection)
Receive (copies incoming TCP data to a user buffer)
Close (closes the TCP connection)
Status (dependable, return information, such as: local socket, foreign socket, window size, TCP connection state, ….)
Abort (causes all pending send and receive operations to be aborted).
Frage 11
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What are the 5 basic processes in a TCP socket implementation?
Open a socket.
Open an input stream and output stream to the socket.
Read from and write to the stream according to the server's protocol.
Close the streams.
Close the socket
Frage 12
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Which are no generic TLDs? Check all that apply:
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.com
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.technikum-wien.at
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.at
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.austria
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.gov
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.edu
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.fhtw
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.cc
Frage 13
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What is contained within a resource record? Check all that apply:
Frage 14
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If a local DNS server starts an iterative query, what is the correct order of inquired name servers? Check the correct answer.
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Authoritative name server – TLD server – root server
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Authoritative name server only, it performs further enquiries
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TLD name server
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TLD server – root server
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Root server – TLD server – authoritative name server
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Root server only, it performs further enquiries