Download The Transport Layer

Layers
(from Tanenabaum:
“Computer Networks”
and
The TCP Layer
Chapter 1)
(Chaper 6)
Network Software
Protocol Hierarchies
a)
Layers, protocols, and interfaces.
Protocol Hierarchies (2)
a)
The philosopher-translator-secretary architecture.
Protocol Hierarchies (3)
a)
Example information flow supporting virtual communication in
layer 5.
Reference Models
The OSI
reference
model.
Reference Models (2)
a)
The TCP/IP reference model.
Reference Models (3)
a)
Protocols and networks in the TCP/IP model initially.
Services to Protocols Relationship
a)
The relationship between a service and a protocol.
Transport (TCP) Services Provided to
the Upper Layers
A
F
D
C
E
B
Connection-Oriented and Connectionless
Services
a)
Six different types of service.
Service Primitives (2)
a)
Packets sent in a simple (or complex) client-server interaction
on a connection-oriented
network.
(Reminder: Berkeley Sockets:)
Transport Connection Primitives
The socket primitives for TCP.
Socket
Programming
Example:
Internet File
Server
6-6-1
Client code using
sockets.
Socket
Programming
Example:
Internet File
Server (2)
Client code using
sockets.
Reminder: headers added by layers
The nesting of TPDUs, packets, and frames.
The TCP Service Model (2)
(a) Four 512-byte segments sent as separate IP datagrams.
(b) The 2048 bytes of data delivered to the application in a single
READ CALL.
The TCP Segment Header
TCP Header.
The TCP Segment Header (2)
The pseudoheader included in the TCP checksum.
TCP Transmission Policy
Window management in TCP.
TCP Transmission Policy (2)
Silly window syndrome.
TCP Connection Establishment
6-31
(a) TCP connection establishment in the normal case.
(b) Call collision.
Connection Release
Abrupt disconnection with loss of data.
Connection Release (2)
The two-army problem.
Connection Release (3)
6-14, a, b
Four protocol scenarios for releasing a connection. (a) Normal case of a
three-way handshake. (b) final ACK lost.
Connection Release (4)
6-14, c,d
(c) Response lost. (d) Response lost and subsequent DRs lost.
TCP Congestion Control
(a) A fast network feeding a low capacity receiver.
(b) A slow network feeding a high-capacity receiver.
TCP Timer Management
(a) Probability density of ACK arrival times in the data link layer.
(b) Probability density of ACK arrival times for TCP.
Wireless TCP and UDP
Splitting a TCP connection into two connections.
Performance Problems in Computer Networks
The state of transmitting one megabit from San Diego to Boston
(a) At t = 0, (b) After 500 μsec, (c) After 20 msec, (d) after 40 msec.
Fast TPDU Processing
The fast path from sender to receiver is shown with a heavy line.
The processing steps on this path are shaded.