VM TCP Optimiser tweaks on Mac OSX - Help!

Hi,

Virgin Media have said to download the TCP Optimiser program for PC's that are having problems on 20Mb, slide the slider over to 20000 and job done! All well and good but I'm on a Mac so this is what I did and I wanted to check if anyone else knew if I was doing it right!

Firstly, when you swing the slider using TCP Optimiser, it reports the number 1027840 as the RWIN number, so taking this setting I put it into IPNetTuner in the kern.ipc.maxsockbuf parameter. Is this right? Also what is the correct MTU setting for VM modems, the 255 one via ethernet? Some say 1500, some 1488, some 1450 anyone know which one is right?

Thanks in advance.

I'll post this in the Mac forums as well just in case!

In reply to:

---

it reports the number 1027840 as the RWIN number, so taking this setting I put it into IPNetTuner in the kern.ipc.maxsockbuf parameter. Is this right?

---

No it isn't. When moving the slider the numbers change. When you click save or OK (can't remember and haven't got the program open) it will then automatically update the registry so nothing by you needs to be done apart from move the slider. Also, I believe it says on the Virgin Media website that they do not support that program with anything other than Windows at the moment so just be careful about the changes you make incase it isn't compatiable with Mac.

Firstly,
I am having problems with the Virgin Media Broadband Network recently.

I have a 20 Mbs connection and was getting up to around 11 Mbs until late. The data transfer rate from Virgin Media hosted files and from Speedtests recently increased significantly.

Over the past few days, download speed starts just great but within a few minutes the download speed trickles to a halt and the modem requires restarting.

These problems materialized with no Broadband Optimization enabled on a recent Mac with OS X 10.4.10

Secondly

Apple includes a Utility called "Broadband Tuner" which both installs and uninstalls changes to TCP stacks and caches in what appears to be similar to the Virgin Media TCP optimizer for Windows. If you cannot find the utility on your machine, it is available for download from the Apple site.

Apple recommends that the utility is only used in high latency very fast networks such as some of the newer fiber networks being installed in the USA.

I tried both enabling Broadband Optimization and disabling it. The changes are system wide (across accounts) and perpetuate on restarts.

While enabled, I tested by downloading some large Newsgroup files. The rate of download was around 10% faster than with the optimization uninstallled. However the "hanging modem" condition is identical for both installed and uninstalled states.

Bottom line

The Optimization software is unlikely to be the cause or remedy for the "hung modems"

It may or may not be a condition only experienced by OS X users. I have a Windows PC on my local network and i experience the same problems.

Any Windows users experiencing "hung modems" over the past three days?

PS - an edit

The problems mentioned have happened at all times of day

Edited by deleted (Wed 22-Aug-07 13:38:44)

Hi gunnersboy,

It isn't compatible with a Mac at all but I took a pc laptop, ran tcp optimiser on it (on my VM BB) and that's where I got the rwin number from, I then wrote that number down and put it into the equivalent software on the Mac (IPNetTuner) I was asking if that was the correct place in that software, I'm pretty sure it is I just wanted confirmation but thanks for the reply.

Hi Sid_Vicious,

Certain pockets of VM BB users can't get 20Mb properly and they are updating the network, I've just got off the phone to VM and this is what they told me, done by the end of the year, pants eh?!

The Broadband Tuner software is automatically included in the main core of the system in 10.4.9 and above but I installed it separately just in case, no joy though!

I was trying to optimise the connection as this seems to have helped a lot of 20Mb connections on PC's so I was trying to see if it would help my rubbish connection on the Mac by optimising it by using the same RWIN value that the PC is using.