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Really sick and tired (and MTU does matter)

sinewave
Grafter
Posts: 297
Registered: 17-08-2007

Really sick and tired (and MTU does matter)

Firstly, I want to say how absolutely sick and tired I am of poor, slow adsl connections. I have been patient and understanding for too long. I have had ADSL for a few months now and at first it was great but recently (as most - if not all of us know) it has been simply intolerable. The fact that it can be consistently good for some time and then "collapse" tells me that someone, somewhere has made bad decisions. Has plusnet over subscribed? Has it "upgraded" without checking that the upgrade will work for sure? Has it failed to put in fail-safe back-up gear for emergencies? Is it a victim of shoddy BT services?

I have read so many excuses and explanations as well as guesses and hear-say. The fact is we are paying for a service that is unreliable and totally frustrating. I can honestly say that I am not and haven't been for many weeks, getting any benefits from changing from the ol' 56k modem.

Now there is this talk of MTU numbers. I am considered by most to be technically capable with computers and hardware but I really, no, REALLY REALLY do not want to become expert in network comms just to surf the net and enjoy video/audio streams (which I'm supposed to be able to do with ADSL haha). But it seems I have no choice. Plusnet won't help me - they "don't support Macs really".

I would walk to another ISP but even if my contact would allow it I'd have to pay more set-up fees etc. and it can take considerable time for the switch. They've got us over a barrel here (I know all isp's are the same about this).

I'm sorry - but this is all really really crap. Actually I'm not sorry.

Secondly, MTU of 1458 really DOES matter. I was told on the phone by tech support that even if I could find out how to change it (they couldn't tell me as I have a mac and its a job for really advanced boffins from space, with two brains), it "wouldn't make much difference". They said you might get a gain of a few kb/s if you're lucky.

The fact is by using IPNetTuner (get it from www.sustworks.com)and crossing a few fingers I found the speed given from ADSL guide goes from a typical value of 97kb/s (40kb/s not uncommon) to 470kb/s. I could not believe this so I changed the MTU back to 1500 and ran three speed tests - all came out to less than 100kb/s. I set MTU back to 1458 and three tests showed >450kb/s consistently. These are actual speeds too - not including overheads. Great!! but for some reason I expect these to drop by tomorrow (or within the hour?).

I don't know whats going on. I don't know what MTU is (they didn't mention this in my networks course in Sheffield Uni). I don't want to know. I pay my £23 every month for plusnet to worry about such stuff. In fact I don't mind if plusnet tells me I have to change some setting or other so long as they tell me how to do it. I JUST WANT A RELIABLE, DEPENDABLE ADSL CONNECTION.

Suggestion: How about a Mac forum - if your support people won't help us maybe we can help eachother.

Tom
(in need of a holiday)
3 REPLIES
N/A

RE: Really sick and tired (and MTU does matter)

I can recommend Singapore... plenty nice girls!!

Inserting the correct MTU, RWIN and other settings on my pc made a 60% difference (improvement) in speed and achieved 100% traansmission efficiency (was about 80%) before.

N/A

RE: Really sick and tired (and MTU does matter)

> I can recommend Singapore... plenty nice girls!!
>
> Inserting the correct MTU, RWIN and other settings on my pc made a 60% difference (improvement) in speed and achieved 100% traansmission efficiency (was about 80%) before.
>
>

I too have tried the tweaks with IP Netuner and found absolutely no difference in speed. Open Transport in Classic Mac operating systems are not sensitive to MTU or RWIN settings.

As for a Mac forum - yes, but I wonder why? The OS is stable, set-ups are simple and Apple have none of the complexity of M$ Windoze. And they're quicker!

hjm
N/A

RE: Really sick and tired (and MTU does matter)

> Firstly, I want to say how absolutely sick and tired I am of poor, slow adsl connections. I have been patient and understanding for too long. I have had ADSL for a few months now and at first it was great but recently (as most - if not all of us know) it has been simply intolerable. The fact that it can be consistently good for some time and then "collapse" tells me that someone, somewhere has made bad decisions. Has plusnet over subscribed? Has it "upgraded" without checking that the upgrade will work for sure? Has it failed to put in fail-safe back-up gear for emergencies? Is it a victim of shoddy BT services?
>
> I have read so many excuses and explanations as well as guesses and hear-say. The fact is we are paying for a service that is unreliable and totally frustrating. I can honestly say that I am not and haven't been for many weeks, getting any benefits from changing from the ol' 56k modem.
>
> Now there is this talk of MTU numbers. I am considered by most to be technically capable with computers and hardware but I really, no, REALLY REALLY do not want to become expert in network comms just to surf the net and enjoy video/audio streams (which I'm supposed to be able to do with ADSL haha). But it seems I have no choice. Plusnet won't help me - they "don't support Macs really".
>
> I would walk to another ISP but even if my contact would allow it I'd have to pay more set-up fees etc. and it can take considerable time for the switch. They've got us over a barrel here (I know all isp's are the same about this).
>
> I'm sorry - but this is all really really crap. Actually I'm not sorry.
>
> Secondly, MTU of 1458 really DOES matter. I was told on the phone by tech support that even if I could find out how to change it (they couldn't tell me as I have a mac and its a job for really advanced boffins from space, with two brains), it "wouldn't make much difference". They said you might get a gain of a few kb/s if you're lucky.
>
put my mtu to 1458 n its its been 470/235 for the last four days altering tcp dos'nt seem to make any differance.