Since dial up uses a default MTU of 576 bytes you will not have the same problems as broadband. If you have problems with both broadband and dial up access then the problem is probably something else. Summary One of the easy and most accurate ways to test for optimum MTU is to do a simple DO S P ing test. You will simply send out ping requests and progressively lower your packet size until the packet no longer needs to be fragmented.
SpeedGuide.net :: Broadband Tweaks, Tools and Info SpeedGuide.net - The Broadband Guide. Cable modems, DSL, Wireless, Network security. Free speed tweaks and TCP/IP tools for optimizing system performance. AmpliFi 1. Using an Ethernet cable, connect a laptop (or any device that allows a wired connection) directly to a LAN port on the modem provided to you by your internet service provider (ISP) and run a speedtest. If the speeds are slow, there may be an issue with the modem or the service. Contact your ISP for help. This issue would be unrelated with Unusual access | DSLReports, ISP Information Forum discussion: I note most ppl state MTU of 1488 is best, but I note throughput drops when I set everything to 1488, and goes back to the better throughput when I reset back to 1500. Is
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May 15, 2020 How to determine the optimal MTU and MSS size - Tips and
From your main cable box outside, you should have a direct cable line to your cable modem. If your line is split to a TV anywhere along the way, you will have reduced Internet performance. If this is the case, try to disconnect the splitter and use another line (split off another TV run perhaps) for the disconnected TV.
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