Service manual

431
SEP 2006
Ver. 1.1
DP-8020E/8020P/8016P
9.4. Transport Layer
9.4.1. TCP (Transmission Control Protocol)
The TCP (Transmission Control Protocol) is an internetwork connection-oriented protocol that corresponds
to the OSI Transport layer. TCP provides full-duplex, end-to-end connections. When the end-to-end
communication acknowledgement is not required, the UDP (User Datagram Protocol) can be substituted for
the TCP at the Transport (host-to-host) level. TCP and UDP operate at the same layer.
The UDP is a connectionless oriented protocol.
TCP Segment in IP Datagram
IP Header
(20 byte)
Application Data
(vary)
TCP segment
IP Datagram
TCP Header
(20 byte)
TCP Segment Outline
Header Length
(4 bit)
Reserved
(6 bit)
Control Flag
(6 bit)
Window (6 byte)
Source Port (2 byte)
Destination Port (2 byte)
Sequence Number (4 byte)
Acknowledgment Number (4 byte)
Checksum (2 byte)
Urgent Pointer (2 byte)
Option
PAD
Data (Segment)
TCP Header Monitoring Sample