I actually logged in to the forums to ask the same question.

I installed a Voom 500 Business line to my premises last week.
I had already a residential line cable with the Superhub2 so all the guy did was to unplug the cable from the SH, connect a splitter to the end of it, and from there two cables, one to the old SH and one to the 'Business' Hitron router.

This is DESPITE I had an unused cable hanging outside my wall ready to be used.
The technician (Virgin subcontractor company) reassured me that this the way they do it and there was no point drilling another hole to my (thick) wall.

I do have huge problems with speed on the Business line however this is due to the GRE tunnel and the static subnet I've been assigned. It's a known problem so I cannot blame the splitter practice... I do have an open ticket though...

If anyone else has solid argument that the splitting practice should NOT be happening please let us know.

Correct.

It's frowned up on because it can have a negative impact on power levels.

In a residential property where someone can have one SH3 and two V6 boxes for example, if they decided to piggy back next door onto yours, you could end up with a useless service.

It's cutting corners.

In reply to a post by wolvesmad:

Correct.

It's frowned up on because it can have a negative impact on power levels.

In a residential property where someone can have one SH3 and two V6 boxes for example, if they decided to piggy back next door onto yours, you could end up with a useless service.

It's cutting corners.

The technician had to connect two attenuators to the Business Hitron router, 1x10 Db and 1x 3Db. Does this mean that actually power is OK (in fact more) and it had to be brought down?
Is there a way of testing the power in both routers to see if they are in acceptable levels?

And what are the acceptable levels?

In reply to a post by netizen_uk:

Is there a way of testing the power in both routers to see if they are in acceptable levels?

And what are the acceptable levels?

Yes. Access the Hitron router web interface (put its IP address in a browser) and view the power levels in the DOCSIS WAN section.

I've been told that downstream power levels should be between -6 to 10 dBmV. Upstream should be between 31 to 51 dBmV. SNR should be more than 34.5db - the higher the better.

In reply to a post by gary333:

If I am reading what you have put correctly then this is not how the Virgin Media network is installed around here.

Each property usually has it's own coaxial cable run from the outside of each house (the brown box or grey if from Telewest/Yorkshire cable days) to the nearest street cabinet

That's the same setup as we have round here, which is why I questioned the fact they split a second connection from mine. I've seen inside my cabinet and there is a cable for every property, each with a tag with the relevant address on.

I've been keeping an eye on my BQM and keep running speed tests, and so far I haven't seen any noticeable difference since it got split thankfully.

The technician is correct, there is no point running two cables into a house when you can split the signal. I would have done the same thing. Essentially the cabinet you connect to is a giant splitter anyway