Assignment Transport – Questions
R1-R4, R6-R11, R14- R18
P1, P5, P8, P22, P24, P29, P30, P42
Assignment Transport - Solution
Review Question - Solutions:
1. a) Call this protocol Simple Transport Protocol (STP). At the sender side, STP
accepts from the sending process a chunk of data not exceeding 1196 bytes, a
destination host address, and a destination port number. STP adds a four-byte
header to each chunk and puts the port number of the destination process in this
header. STP then gives the destination host address and the resulting segment to
the network layer. The network layer delivers the segment to STP at the
destination host. STP then examines the port number in the segment, extracts the
data from the segment, and passes the data to the process identified by the port
b) The segment now has two header fields: a source port field and destination port
field. At the sender side, STP accepts a chunk of data not exceeding 1192 bytes, a
destination host address, a source port number, and a destination port number.
STP creates a segment which contains the application data, source port number,
and destination port number. It then gives the segment and the destination host
address to the network layer. After receiving the segment, STP at the receiving
host gives the application process the application data and the source port number.
c) No, the transport layer does not have to do anything in the core; the transport
layer “lives” in the end systems.
2. a) For sending a letter, the family member is required to give the delegate the
letter itself, the address of the destination house, and the name of the recipient.
The delegate clearly writes the recipient’s name on the top of the letter. The
delegate then puts the letter in an envelope and writes the address of the
destination house on the envelope. The delegate then gives the letter to the
planet’s mail service. At the receiving side, the delegate receives the letter from
the mail service, takes the letter out of the envelope, and takes note of the
recipient name written at the top of the letter. The delegate than gives the letter to