157 lines
2.7 KiB
HTML
157 lines
2.7 KiB
HTML
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>A few general remarks about tunnels:</TITLE
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>5.1. A few general remarks about tunnels:</H1
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>Tunnels can be used to do some very unusual and very cool stuff. They can
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also make things go horribly wrong when you don't configure them right.
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Don't point your default route to a tunnel device unless you know
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<EM
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>EXACTLY</EM
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> what you are doing :-). Furthermore, tunneling increases
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overhead, because it needs an extra set of IP headers. Typically this is 20
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bytes per packet, so if the normal packet size (MTU) on a network is 1500
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bytes, a packet that is sent through a tunnel can only be 1480 bytes big.
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This is not necessarily a problem, but be sure to read up on IP packet
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fragmentation/reassembly when you plan to connect large networks with
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tunnels. Oh, and of course, the fastest way to dig a tunnel is to dig at
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both sides.</P
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>IP in IP tunneling</TD
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