The vdsl modem may well have it covered.
"The active Ethernet EU port on the VDSL2 Active NTE will support:
· 10/100Base-Tx with RJ-45 connectivity
· Auto-negotiation and MDI/MDIX auto-sensing.
· Data transfer at wire-speed for all packet sizes.
· Built-in layer-2 switch
The technical specification of the interface connections provided by the NTE device is
described in SIN 360, Ethernet Customer Interfaces, and Interface Characteristics"
From the FTTC handbook May 2010.
(However I don't dispute standard pppoe MTU packet size is "historically" 1492 bytes. )
It is easy to test for yourself just use the SG TCP Optimizer app it is free, download it from http://www.speedguide.net/downloads.php. It is a registry editor so does not leave any programs running in the background. If you are going to use the app to mess with your TCP setting be careful as the optimal setting will prevent UDP connections working in some instances, i.e. edit your registry at your own risk.
If you read some of my threads on the topic ....
You'll see I;ve been doing it for years ... not lately though. 🙂
It's been a few months since I was invesigating this (I started the thread), so I have forgotten most of what I learnt about.
I kept the default MTU setting of 1492 on my Tomato powered router, and kept the Windows default of 1500.
Is this fine?
As well as wanting the fastest BT Infinity connections settings, my ethernet LAN speeds is important as well. Does the Windows MTU setting affect this?
I really ought to understand all this stuff, but my local college has cancelled the CCNA course twice in a row now, due to low demand.
I have a gigabit ethernet LAN with a HP ProLiant server (with four ethernet ports, running VMware ESXi and multiple server virtual machines), thee client machines and a couple of laptops connecting through wifi, and I use VLANs and jumbo frames.
If you're using 1492 on the router ....
You need it on the LAN machines as well , otherwise your router will fragment packets at 1500.
It's all on here somewhere, check posts by myself, PheeragHfre and IanC
Stuff here on kitz, http://www.kitz.co.uk/adsl/MTU.htm
I was googling the question "bt router jumbo frames" and came across this post as my NAS router can speed up transfer acorss my home LAN if the router of switch can use Jumbo Frames.
So this is why you may need to change your MTU setting.