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Version 0.0.0 @ 03:55/08.07.2000

Decomposition of a TCP Packet


Bits used per field:
0....... 8....... 16...... 24......
(<--------32-bits-wide-------->)
16-bit-Src-Port-
16-bit-Dest-Port
-----32-bit-sequence-number-----
--32-bit-acknowledgment-number--
HdLn
Resrvd
U
A
P
R
S
F
16-bit-wind-size
16bit-TCP-Chcksm
16bit-urg-pointr
-----------Options(?)-----------
--------data/payload(?)---------

The above is an example of an TCP Header. Rows 1 through 5 are commonly used, and when options are included in the header, then rows 1 through 6 or more depending upon how many 32-bit option words are used by special options. The payload contained is the encapsulated data from the upper layer. For example, a Synthesis request from a client to a server to create a connection and session.

This ends the brief preview of an TCP packet.

Comments and/or suggestions for this?: Email me at: dugan@passwall.com
Attempts have been made to make the tables appear as they should for LYNX users by forcing a common field width for fields being used by padding them with other printable characters. This is meant to allow for LYNX users to see the tables much like the Netscape and other web browser worlds might show them. However, from personal experience, some versions of LYNX still manage to munge the tables, making them use up several pages. It seems to be a problem with how earlier versions of LYNX dealt with tables, but the problem has not been entirely isolated.
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