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Version 0.0.0 @ 03:55/08.07.2000

Decomposition of a UDP Packet


Bits used per field:
0....... 8....... 16...... 24......
(<--------32-bits-wide-------->)
16-bit-Src-Port-
16-bit-Dest-Port
16bit-Len-of-UDP
16-bit-Checksum-
--------data/payload(?)---------

The above is an example of an UDP Header. UDP is an unreliable protocol where no attempt is made to keep track of packets as to being in a sequence, order, or verify that they were received. Checks are made to see if the packet appears to be the same packet transmitted by evaluation of a checksum and comparison to the packets checksum. These packets are dropped if the destination calculations of the checksum differs from the packets claimed checksum.

This ends the brief preview of an UDP 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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