Summary CSCI 4500: Chapter 3: Transport Layer | Summaries

CSCI 4500: Chapter 3: Transport
Layer
1. What are
logical communication(btw app processes),
trans- port
end sys- tems(sender/receiver), and the
services and
internet(TCP/UDP)
protocols?




2. sender breaks application messages into segments, passe
to
network layer
3. receiver reassembles segments into messages, passes to
appli-
cation layer

4. analogy for 7. transport layer actions receiver
the transport
layer


5. transport vs net-
work layer


6. transport layer
actions sender




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, CSCI 4500: Chapter 3: Transport
Layer
segment from IP checks
header values


Network layer:
logical
communication
between hosts
Transport layer:
logical
communication
between process- es
(relies on,
enhances, network
layer services)

is passed
an
application
layer
message
determines
segment
header
fields
values
creates
segment
passes segment to IP


r
e
c
e
i
v
e
s
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, CSCI 4500: Chapter 3: Transport Layer | Summaries

extracts application-layer message
demultiplexes message up to application via socke

8. TCP(Transmis- reliable in-order delivery
sion Control congestion control
Protocol) flow control
connection setup

9. UDP (User Data- A no-frills, lightweight transport protocol,
gram Protocol) providing min- imal services, DNS uses this
protocol, connectionless, unreliable, unordered
delivery, best effort(UDP segments may be
lost/delivered out-of-order to app), [RFC768]
10. Services not
pro- vided by delay guarantees
TCP and UDP bandwidth guarantees

11. multiplexing A form of transmission that allows multiple signals
to
travel simultaneously over one medium

12. multiplexing handle data from multiple sockets, add transport
at sender head- er(leaving the center)



13. demultiplexing A process that converts the multiplexed signals to
inde-
pendent signals

14. demultiplexing use header info to deliver received segments to
at receiver correct socket(coming back to center)



15. multiplexing multiplexing — receiver side(happens at
vs transmitter side) demultiplexing — transmitter
demultiplexing side(happens at receiver side)

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, CSCI 4500: Chapter 3: Transport Layer | Summaries




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