CH 14 set

Assume that a host with IP address 10.1.1.10 wants to request web services from a server at 10.1.1.254. Which of the following would be the correct socket pair?

10.1.1.10:1099, 10.1.1.254:80

T/f The two fields that are the same in both the UDP and TCP header would be the sequence and acknowledgment fields.

False

True or False: UDP provides reliability and is faster than TCP.

False

Why is UDP desirable for protocols that make simple request and reply transactions?

It has low overhead

Match the well-known port number with the corresponding port number.

SSH (Secure Shell): 22 Telnet: 23 HTTPS: 443 IMAP: 143 TFTP: 69

Which control bit flags are used during the three-way handshake?

SYN and ACK

True or False: The TCP Header consists of 10 fields in a 20-byte header.

True

t/f UDP reassembles data in the order in which it is received.

True

Which of the following is a stateless best-effort delivery transport layer protocol?

UDP

Which transport layer protocol would be used for VoIP applications?

User Datagram Protocol (UDP)

What field does the destination host use to reassemble segments into the original order?

sequence number

Which of the following would be valid source and destination ports for a host connecting to a DNS server?

source: 49,152, destination: 1812

Which of the following would be valid source and destination ports for a host connecting to an email server?

source: 49,152, destination: 25

Which layer is responsible for establishing a temporary communication session between the source and destination host applications?

transport layer

Which port group includes port numbers for FTP, HTTP, and TFTP applications?

well-known ports

Match each description with the appropriate TCP header field.

A 4-bit field known as "data offset" → Header Length, A 16-bit field used to identify the port number of the sending application → Source Port, A 16-bit field used for error checking of the segment header and data → Checksum, A 32-bit field used for data reassembly purposes → Sequence Number, A 16-bit field used to indicate the number of bytes that can be accepted at one time → Window Size, A 6-bit field that includes bit codes, or flags, which indicate the purpose and function of the TCP segment → Control bits, A 32-bit field used to indicate that data has been received and the next byte expected from the source → Acknowledgment number

t/f The sequence number field in the TCP header is used for flow control.

False

Which two applications would use the UDP transport layer protocol? (Choose two.)

TFTP, VoIP

What happens when a sending host senses congestion?

The sending host reduces the number of bytes it sends before receiving an acknowledgment from the destination host.