Thread: PPPoE clarification needed

Hi Guys,

After finding tutorials here and other places on the web, configured my MT800 to PPPoE as I had to dial everytime. Now I don't see the same steady speed. It varies very frequently and if am downloading a torrent, webpages don't even open up!

Can you please tell me if I did anything wrong? Any settings? FYI, no settings in uTorrent have been changed. FF has direct access to internet, no proxy nothing.

I just read somewhere that MTU value does make a difference, but dependent on the service provider. I have it as 1492. But with the default value that comes up in the router page, I don't get the 'Status' option to set the WAN to 'Always on'. What is the MTU value in the first place? Please enlighten moi!

Awaiting a reply!

MTU is Maximum Transfer Unit.

For any data exchange the data is sent in packets. MTU decides the packet size. Each packet contains the basic data and an 8 bit checksum. The packet data is always a multiple of 8 (max = 1492 for ADSL) and 8 bits are added later to this.

The higher the packet size, the lesser is the number of packets per data load and thus lower is the time required to downnload/upload the complete page/file/etc. But ADSL cannot handle a very large packet size and 1492 is the max in most cases. Sometimes redicing the MTU helps. I will generally leave the MTU untouched - if you have problems uploading files as attachment to Yahoo/Gmail, etc. then only modify it. Try reducing the MTU by a factor of 16 everytime and check.

p/s. Some routers user 1500 as MTU which is also fine (it is 1492 + 8 (checksum)). This is because such routers do not add checksum as default.

In such routers, you must specify the MTU as 1500 and router will automatically reserve last 8 bits for checksum. If you specify MTU as 1492 then data size will be 1484 and 8 bits will be reserved for checksum.

For other routers, checksum is automatically added later - in this case MTU should be 1492 because router will add 8 bits automatically to it.

I do not know much more than that - check wikipedia for MTU.

By thor, am loving this website.

Thanks a bunch for the useful info. Will check the differences as suggested n get back tonight!

@musik.maniac, here's a little tidbit that may help your web page loading while torrents are running...

manually set a maximum upload speed in utorrent if you've not done so already...set it to around 10-20 kbps to start off with.

I can't guarantee it will work (I myself use Azureus) but it did work like a charm for me! Not only did I start seeing better UPLOAD speeds in torrents (needed for a better share ratio), I also was able to browse websites, etc. with almost no difference than with torrents off!

At least in Azureus, capping your upload speed will tell the program to allocate only so much of your upstream bandwidth. When the default (unlimited) option is used, you'll have almost no UL bandwidth to send data to websites, etc.

hope that helps!

@pjaveed :

My upload is always set to 1kbps, max would be 5 kbps after the downloading is done or if the downloading is stuck in the nineties. As my torrents aren't from the ratio sites, works most of the time.

@just4kix :
I tried 1500, no difference. Will try a lesser value today.