Networking 2 Chapter 9
What range of addresses traditionally defines a well-known port address?
0-1023
____ is detected whenever three or more duplicate ACK packets (known as a triple-ACK) or timeout events occur, and timeout events are considered more serious than duplicate acknowledgments. 1) Congestion 2) fast retransmit 3) SKN flooding 4) slow start 5) windowing
1
Which of the following services are characteristics of connection-oriented protocols and not connectionless protocols? Choose all that apply 1. explicit transmission acknowledgment 2. delivery guarantees 3. message-level checksum in header 4. segmentation and reassembly 5. connection handling
1,2,4,5
Which statements define the edges of the TCP sliding window mechanism? (Choose all that apply.) 1) all data that was received 2) acknowledged data plus the receiver's window size 3) all data that was acknowledged 4) all data pending transmission
2,3
Which of the following values are valid TCP Flag settings? choose all that apply 1) NULL 2) ACK 3) FIN 4) SYN 5) PSH
2,3,4,5
What does TCP use to track the transfer of data and its successful delivery? (Choose all that apply) 1) logical connection between peers 2) acknowledgments 3) retry mechanism 4) sequence numbers
2,4
The Fast Recovery process dictates that when a host receives three duplicate ACKs, it must immediately start retransmitting the ____ without waiting for the retransmission timer to expire. 1) duplicate ACKs 2) 3-way handshake 3) lost segments 4) byte streams 5) duplicate segments
3
The ____ field value defines the destination application or process that uses the IP and UDP headers. 1) type 2) dynamic port number 3) source port number 4) None of these choices 5) protocol
4
Which of the following services does UDP provide? 1)optional header checksum 2) explicit transmission acknowledgment 3) reassembly 4) segmentation 5) identification of source and destination port address
5
____ is the overloading of the network or a receiver, and it occurs when there is too much data on the network medium.
Congestion
UDP is an ____ protocol, which provide the simplest kind of transport services because they simply package messages, taken as is from the TCP/IP Application layer, into datagrams.
Connectionless
the ____ flag is used to indicate that the host completed a transaction.
FIN
Datagrams are not sequenced but they are acknowledged. T/F
False
For applications, such as RIP, that rely on regular updates of routing tables and track timeout values as part of ordinary behavior, the extra reliabilty of TCP is absolutely necessary. T/F
False
Historically, UDP is a more important transport than TCP. T/F
False
Identical UDP and TCP port numbers always map to the same TCP/IP protocol or service. T/F
False
TCP keep-alives are enabled by default on Windows XP, Windows Vista, Windows 7, Windows Server 2003, and Windows Server 2008, although any application may disable TCP keep-alives, if desired by its programmer. T/F
False
The TCP connection termination process requires six packets. T/F
False
The current TCP window size is always the greater of what the network and the receiver can handle at any given moment. T/F
False
UDP offers connection-oriented services with sequencing, error recovery, and a sliding window mechanism. T/F
False
________________ is the organization that defines the range of numbers that identifies dynamic ports
IANA
____ is caused when enough data is sent to a TCP host to fill its receiver buffer, thereby putting the receiver in a zero-window state.
Silly window syndrome
What makes up the value in the UDP Length field of the IPv6 pseudo-header when using UDP for the transport protocol?
The length of the UDP header plus the data
Although connectionless protocols don't track transmission behavior or completeness of delivery (that's what best-effort delivery means), they can optionally include a checksum for each datagram. T/F
True
TCP half-open connections occur when the handshake process does not end successfully with a final ACK. T/F
True
TCP is robust and reliable but it carries a lot of baggage. T/F
True
TCP was designed in an era when 300-bps communication was considered fast, and noisy lines or intermittent communications problems made a long-haul, reliable transmission of data inherently risky without access to a robust, reliable transport service. T/F
True
UDP is the only connectionless TCP/IP protocol at the Transport layer. T/F
True
When the Protocol field of an IP header contains the value 17 (0x11), the UDP header follows the IP header. T/F
True
Is a simple protocol used by applications that contain their own connection-oriented timeout values and retry counters, similar to those provided by TCP.
UDP
Overloading a receiver occurs when the number of data bytes is greater than _______.
advertised window
TCP has _______defined congestion control mechanisms to ensure the most efficient use of bandwidth along with quick error and congestion recovery.
four
TCP hosts create a virtual connection with each other using a 3-step ____ process.
handshake
TCP hosts create a virtual connection with each other using a__________.
handshake process
Where is TCP data stored when it is received?
in the TCP buffer area
the tcp process used to maintain an active connection between peers is called ___.
keep-alive
Once a TCP connection is established, a(n) _____ process can maintain the connection when there is no data sent across the wire.
keep-alive process
The ____ process guarantees that packets are ordered properly and protects against missing segments.
sequence and acknowledgement
When the UDP checksum is calculated for IPv6, what is the result if the checksum value is 0?
the 0 is changed to the FFFF hex value and placed in the UDP header
From where does the IPv6 pseudo-header acquire the information for the Upper-Layer Packet Length field when using TCP as the transport protocol?
the value in the payload length field in the IPv6 header
what sequence of events signals the tcp fast recovery process?
three sets of duplicate ACKs
