In computer networking, the maximum transmission unit (MTU) is the size of the largest protocol data unit (PDU) that can be communicated in a single network layer transaction. The MTU relates to, but is not identical to the maximum frame size that can be transported on the data link layer, e.g. Ethernet frame.

Windows machines from visa on will auto determine the MTU and would match the router setting. @Oldjim For what it's worth: Plusnet TG582n router will by default use a MTU of 1492 when configured for pppoe (fibre). When configured for ADSL it defaults to a MTU of 1500. Don't know about the 2704n. MX Series. You can configure the maximum transmission unit (MTU) and maximum receive unit for Point-to-Point Protocol (PPP) subscribers. This configuration is supported for the following PPP subscribers: MTU. Typically, the largest Ethernet frame that can be transmitted without fragmentation is 1500 bytes. PPPoE adds another 6 bytes of overhead and the PPP field adds two more bytes, leaving 1492 bytes for IP datagram. Therefore max PPPoE MRU and MTU values must not be larger than 1492. If you selected PPPoE as ICT, you have the option to leave the default MTU as Auto and it will be auto sensing but the recommended PPPoE MTU that our router will select might still be 1492 bytes. You can also select Manual MTU but change the MTU size from 1492 to 1500 bytes. MTU for Ethernet is 1500 and for my PPPoE v2 (ISP) is 1492 bytes. Is it useful to go for 1492 in my Archlinux too or is it just a myth? I did that in the past, but I haven't recognized any benefits.

The Point-to-Point Protocol over Ethernet (PPPoE) is a network protocol for encapsulating PPP frames inside Ethernet frames. It appeared in 1999, in the context of the boom of DSL as the solution for tunneling packets over the DSL connection to the ISP's IP network, and from there to the rest of the Internet.

Point-to-Point Protocol over Ethernet - Wikipedia

PPPoE Dual Ethernet Internet Sharing. Basic steps to configure IPNetRouter with PPPoE or LANTunnelBuilder 5.0.9a in a dual ethernet setup: On the gateway machine, use the TCP/IP control panel to configure the PPPOE driver for the DSL/ADSL modem as instructed by your service provider.

MTU Issues¶ Issues with upload speed frequently end up being issues with the MTU. If the MTU on pfSense® software (default 1500), is higher than the MTU of the upstream link, it can result in packets being fragmented, lost, or otherwise mishandled. Setting MSS clamping on the WANs or changing the MTU of the interface may help. Point-to-Point Protocol over Ethernet - Wikipedia The Point-to-Point Protocol over Ethernet (PPPoE) is a network protocol for encapsulating PPP frames inside Ethernet frames. It appeared in 1999, in the context of the boom of DSL as the solution for tunneling packets over the DSL connection to the ISP 's IP network, and from there to … Troubleshooting MTU Size in PPPoE Dialin Connectivity - Cisco