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If one's internet connection is being limited by a unit that restricts the transfer, how would one be able to change a setting related to it - more specifically the MTU

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Make sure path discovery is enabled? – Ken Sharp Jul 28 '15 at 4:27
up vote 11 down vote accepted

What is MTU?

Your MTU - also known as the Maximum Transmission Unit - value is a restriction set to have a limit of the amount of data that may be sent per packet. You can check more details by visiting the Wikipedia Page.

How do I check and edit the MTU?

The way you can check your Maximum Transmission Unit is by accessing the Wireless Settings via the indicator on the panel at the top of your desktop.

Click on wireless indicator, and then select 'Edit Connections...' from the menu.

You will see a line of tabs:

line of tabs

And should select the one which holds the Internet connection you're having trouble with. For this example, I have made a fake Internet connection. The settings should be the same for all types of connections.

Select the connection you're having trouble with, and click 'Edit'.

Wired Connection 1 and Edit

By pressing edit, the following window will pop up:


You should then check the MTU value. If it is not on Automatic, you may want to change this.



I know they're the most well done ticks and crosses ever. No need to be jealous.

If your data is larger than the MTU, then it is simply split up into multiple packets.

Thanks to Andrew for clarifying and correcting

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-1. The MTU is a limit on the amount of data that may be sent per packet. If your data is larger than the MTU, then it is simply split up into multiple packets. Automatic is not necessarily the best setting for all cases, and your connection won't terminate for being 'over the set number of bytes.' – Andrew Feb 24 '14 at 15:58
Thanks for letting me know. I'll fix it now :) – Mochan Feb 25 '14 at 5:36
Downvote taken back. – Andrew Feb 25 '14 at 13:50
On wired connections with PPPoE you should reduce to 1460. For wLAN connectivity an MTU of 500 or below can make a huge difference. At my side longer packets have a too high chance to collide on the shared medium, so low MTU with bigger TCP receive window rise the probability, that a missing packet will be detected and retransmitted more early. – Tino Apr 11 '15 at 23:27

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