mssclampfw intro
This kernel module, designed to operate on a forwarding or masquerading Linux 2.2 or 2.[3-4] gateway that has attached tunnels or encapsulation interfaces with reduced packet sizes (like PPPoE) connected to networks with ICMP blackholes (such as Bell Canada's Sympatico HSE), prevents Path MTU Discovery failures (causing a TCP connection to hang as soon as the remote host tries to send full packets) by patching the MSS option in TCP SYN packets down to the safest value according to the outgoing device's MTU.
Idea and implementation by Marc Boucher <marc@mbsi.ca> Linux 2.2 CONFIG_FIREWALL support done under contract for Rebel.com. Check out the Netwinder/OfficeServer at http://www.rebel.com/netwinder/ !
Copyright (C) 1999, 2000 Marc Boucher and Rebel.com. All rights reserved.
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