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>> > A while back I was having networking issues. I eventually tried |
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>> > drastically lowering the MTU of all the systems onsite and the issues |
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>> > disappeared. I always thought the issue was due to the MTU on our |
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>> > modem/router. Today I read that AT&T DSL requires a 1492 MTU so I |
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>> > increased the MTU of our systems up to 1492 and haven't had any |
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>> > issues. Do certain ISPs require you to change the MTU of your entire |
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>> > network, or is this likely due to our AT&T modem/router itself? |
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>> |
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>> AFAIK the MTU is defined for every network interface separately. For an |
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>> ADSL connection it is common that a lower MTU is needed because of the |
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>> PPPoE header information that is encapsulated in the ethernet frames. |
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>> But in that case it is sufficient to lower the MTU just for the WAN |
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>> interface that is connected to the DSL modem. |
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>> If you don't use protocol encapsulation in your LAN then there should |
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>> be IMHO no reason for lowering the MTU of your internal interfaces. |
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>> |
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>> -- |
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>> Regards |
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>> wabe |
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> |
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> MTU is per network interface but you really don't want to end up having |
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> your router fragment every IP packet because systems on your subnet are |
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> using a larger MTU. |
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> |
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> Todd |
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That makes sense. So in my case, I'm thinking 1492 MTU on every |
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interface in the network. |
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So I'm sure I understand, should everyone with a DSL connection set an |
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MTU of 1492 (or potentially lower) on all of their network interfaces |
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to avoid packet fragmentation? |
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- Grant |
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