Need help regarding MTU, MCC, ICMP Headers ... !!!

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From: pg
Date: Mon, 27 Oct 2008 08:45

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Hello !!

I'm trying to set the MTU value of a new PC -- dual boot, Linux &
Windows -- and the lan card, the adsl modem, etc.

Since I'm not so bright, I went online to check. The more I check,
however, the more I got confused.

On this page http://help.expedient.com/broadband/mtu_ping_test.shtml
( scrolling down to #5 where it ) says "Add 28 to that number (IP/ICMP
headers) to get the optimal MTU setting"

On this page, http://www.speedguide.net/read_articles.php?id=157
however, ( scrolling down to TCPWindowSize ) it is telling me that
"MSS is generally MTU - 40 (20 byte TCP and 20 byte IP headers)" !

Which one is correct?

Just exactly how much do all the headers add on to a packet?

28 bytes or 40 bytes??

Let's say I've done the "MTU Ping Test" to various websites, and has
obtained 1452 as _the_ optimum number. My question is this ---

		What's the correct MTU setting?

			Is it 1480 (1452 + 28) ?
		or
			Is it 1492 (1452 + 40) ?

In Windows, what numer should I set for the TCPWindowSize, the
GlobalMaxTcpWindowSize, the TcpWindowSize and so on?

Is the MTU value the same for Linux, Solaris and Windows??

Please help !!

Thank you !

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From: pg <penang@catholic.org>
Newsgroups: comp.security.firewalls,comp.os.ms-windows.networking.misc,comp.unix.solaris,microsoft.public.windowsxp.general,24hoursupport.helpdesk
Subject: Need help regarding MTU, MCC, ICMP Headers ... !!!
Date: Mon, 27 Oct 2008 01:45:28 -0700 (PDT)
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